주)
1.검사비는 요청하는 용접검사 종류와 수량에 따라 정산되므로 시전문의시 개략적인 금액을 안내 할 수 있습니다.

2.검사기간은 요청하는 용접검사 종류 외 수량에 따라 다르지만 만족스런 검사준비 되면 최단시일 내 완료가능합니다.

선급제품과 관련된 일반 용접 규정

  • 범위
    • 이항의 내용은 선박 또는 기타 해상 구조물, 또한 그 선박 또는 구조물에 설치 사용될 압력용기, 기계류 및 장비류들의 신조, 개조, 변경 또는 수리과정에서 행해지는 모든 용접자격부여 및 시험들에 적용됩니다.
    • 아래 기술되는 규정들은 또한 로이드 선급이 규정을 발행한 또는 이해 관계를 갖고 있는, 위에 기술한 것들 외의, 다른 응용품과 관련한 모든 용접 작업에도 적용됩니다.
    • 아래 기술된 규정의 모든 측면을 준수함을 보증하고, 발생하는 규정을 벗어난 모든 것에 대해 검사원에게 알리는 것은 제조자의 책임입니다. 규정에 맞지 않는 것들은 모두 그에 따른 시정조치와 함께 부적합으로 기록되어야 합니다. 만약 그렇지 못할 경우, 그 제관작업은 규정을 준수하지 않는 것으로 간주합니다.
    • 용접 시험은 제조자의 작업장에서 검사원의 입회 하에 실행되어야 합니다. 용접절차 자격부여시험과 용접사 자격부여 시험은 제관 또는 건조 전 실행하여 승인을 받아야 합니다.
    • EN, ISO, JIS, ASME 또는 AWS에 따라 행해진 용접절차시험들을 인정할 수 있는 경우가 있는데 그 경우 최소한, 그 시험들이 이 규정의 기술적인 취지에 동등하거나 부합한다는 것에 대해 담당 검사원이 만족해야 합니다.
    • 과거에 실시하였던 용접시험들의 경우, 그 시험들이 로이드 선급에서 인정할 수 있는 독립적인 기관에서 감독했으며 담당 검사원이 그 시험의 진위에 확신을 가질 수 있는 경우에, 인정할 수도 있습니다.

      ※용접사의 계속적인 승인을 위해 해당 관리 제조자는 용접사 관리대장을 준비하고 주기적인 자체시험결과를 기록 보관 하여야 한다.

      ※용접사 자격 취득 후 LR검사가 무경험일 경우 재승인을 위해 용접시험 TEST를 필요에 따라 실시 요구 된다.

    • 용접시험 이행에 대한 책임은 제조자에 있습니다. 용접시험들 중, 기계적 시험, 비파괴 시험 및 열처리 등은 제조자가 협력사에 줄 수도 있습니다. 단, 협력사는 제조자의 기술적인 관리와 지시 하에서 업무 수행을 하며, 그 조치들 시작 전 그러한 조치들이 검사원과 동의가 되어야 합니다.
    • 이 규정에서 “제조자” 라는 용어는 용접을 실행하는 공장 또는 조직을 얘기하며 조선소, 부분 선체 건조업체 또는 조립업체 또는 소재 제조업체를 일컫습니다.
  • 설계
    • 용접절차 자격부여 시험은 승인된 도면 또는 설계에 따라 만들어진 제관 용접들이 규정에 부합하는 성질들을 가지고 있음을 보증할 수 있어야 합니다. 어떠한 절차가 특정용도에 적합한 가를 확립하고 문서화하는 것은 제조자 책임입니다.
    • 이규정의 요구사항들은 용접부와 열영향부의 기계적 성질과 관련이 있지만 제시된 사용목적에 적합한가를 보증하기 위해 때때로 특정 재질에 대해서는 다른 종류의 시험들이 요구될 수도 있습니다. 예를 들면 부식 또는 피로 시험이 있습니다.
  • 재료
    • 시험에 사용될 재료는 검사원의 사전 동의를 득하지 않는 한 실제 용접제관에 사용될 재료들과 똑 같은 형태이어야 하며 똑같은 제조방식으로 만들어져야 합니다.
    • 시험에 사용될 재료들은 원 제조사의 재료시험 성적서에 따라 적합하게 표식이 되어 재료와 성적서의 일치성을 증명 할 수 있어야 합니다.
  • 용접 시험의 실시
    • 모든 용접과 그에 따른 시험들은 로이드 선급 규정인 용접절차 자격 규정에 따라 실시 되어야 합니다.
    • 제조자는 다음과 같은 일에 책임이 있습니다. 즉, 시험의 감시, 다음 항에서 요구하는 모든 용접변수 기록, 비파괴 검사 보고서 및 기계적 시험 기록 등을 수집 종합하여 검사원에게 제출하여야 합니다.
    • 시험을 실시할 시험실 및 시험기관들은 필요한 장비를 잘 유지보수하고 적합하게 교정되어야 합니다. 재료의 제조시험 인증에 대한 규정 ( Rules for Manufacture, Testing and Certification (이하 ”재료규정”) )의 Chapter 2, Section 1.2.1에 따라 시험실 직원들의 기능은 적합한지 또한 자격은 적합하게 주어졌는지를 검사원이 만족할 수 있어야 합니다.

Section 2 강의 용접절차 인증시험 (WPS)

  • 일반 규정
    • 이항의 규정들은 탄소, 탄소-망간 강 및 저합금 강재의 용접 절차의 시험규정에 관련된 것입니다. 또한Austenitic/Ferritic/duplex stainless 강, 알루미늄 및 동합금에 대한 추가적인 요구사항들은 3항과 4항에 각각 규정되어 있습니다.
    • 용접절차 인증시험 개시 전, 제조자는, 시험 중 수행되어야 할 열처리, 소재, 용접 이음매, 용접 자세, 용접 방법 등을 상세히 기술한 예비 용접 절차서 (pWPS)를 담당 검사원에게 제출하여야 합니다. 예비 용접절차서는, 시험이 시작되기 전에, 검사원에게 정보제공을 위해 제출 되어야 합니다.
    • 각각의 용접 절차서에 적용 되어야 할 시험의 종류와 범위는 다음 항들의 규정에 따릅니다.
    • 용접절차 승인을 위해서는, 이 항에 규정되어 있는 용접절차 인증시험이 만족스러운 결과를 낼 수 있도록 수행 되어야 합니다. 용접절차서는 용접절차 자격시험에서 얻은 시험결과에 따릅니다.
  • 용접 변수
    • 용접자격시험 조건은 용접운용이 제품에 적용되기 위해서는, 적절한 용접 변수가 용접및 시험중 제조자에 의해 다음의 항목이 기록되어야한다:

      (a)절차서 고유 번호 및 용접일자; (예: WPS,PQR,WPQ 번호)

      (b)소재종류, 등급, 제품 형상, 규격 및 식별; (예: 철판, 고장력강, 두께 범위 및 소재 성적서와 일치 여부)

      (c)Tack 용접을 포함한 용접 방법; (예: SAW, SMAW, GTAW, FCAW, GMAW, SMAW+SAW, FCAW+SMAW, GTAW+FCAW 등)

      (d)용접 이음매 형상, 치수 및 표면 상태;(예: 맞대기 이음, 철판 두께, 베벨 각, 루트 간격 및 루트부 Toe height 및 표면 가공여부 등)

      (e)용접 자세; (예: 아래보기, 수평보기, 수직 상향, 수직 하향 및 위보기)

      (f)용접 기법; 즉 Weave 용접법, 다극 용접봉 사용 등, 기타; (예: 직선/위브(Weave), 단전극/ 다전극 또는 수동/ 자동 등)

      (g)플럭스, 실드 (차폐)가스등을 포함한 용접봉; 용접봉의 승인여부 점검 및 적절한 용접봉 선택. 다음 주소로 승인된 용접봉 확인가능 : https://www.cdlive.lr.org/information/default.asp?preOpen=Approvals

      (h)용접봉 관리; 즉, 용접봉 굽기 또는 건조 상태 등 (용접봉 제조 업체의 지침에 따른 용접봉의 건조 및 구운 상태유지).

      (i)용접 요소들, 즉, 전류, 전압, 이동 속도 등

      (j)용접층의 수 와 순서 ;(예: 단층/다층용접, 입열량 및 HAZ부의 용접 시 받는 열 영향을 고려한 용접순서)

      (k)Backing (받침) 가스를 포함한 Backing 재료

      (l)예열 및 층간온도; (예: 용접봉 등급 (즉 로이드 에서 부여한 Grade) 에 따라 탄소강과 탄소망간강 (Carbon and carbon manganese steels) 에 있어 예열은 재료규정 Chapter 13 의 Table 13.2.1에 따름.

      (m)루트부 용접 검사와 청소에 사용된 방법; (예: 용접부 검사, 그라인딩 또는 와이어 브러시에 의한 적절한 청소방법 선택)

      (n)후열처리를 위한 온도 및 시간; (예, 재료 제조시험인증에 대한 규정의 Chapter 13 의 Table 13.4.2 또는 13.4.3 의 압력용기 용접 시 후열처리 규정.)

      (o)특수 용접 단면 또는 윤곽에 대한 요구사항.
  • 그 외 다른 변수들은 특수한 용접 방법이나 적용에 따라 기록할 수도 있으며 검사원과 합의가 되어야 합니다. 예를 들면 Pulse 용접의 경우 최고와 최저 전류와 사이클의 시간, GTAW 용접의 경우 용접봉 종류 및 노즐의 크기 등.
제목 요약 내용 관련 규정
2.3 용접 시험 시편
검증 코드, 사양서용접 공정및 기술용접 자세이음매형태소재 형태
용접절차 시험은 실제 구조물에 쓰여질 용접 방법과 자세를 이용해서 실시 되어야 함.
용접시험 시편은 실제 구조물의 상태를 대표해야 하고 실제 제품용접에 사용되는 것과 같은 방식으로 용접 되어야 한다. 사전 제작용 Primer가 조선소에서 사용될 경우, 이것 또한 시험시편에 반영되어야 함
재료규정Ch 12 Sec 2.3.1
Plate를 이용한 시편의 경우 용접방향과 관련하여 철판의 롤링방향이 고려되어야 한다. 시험에 사용될 재료가 종 방향의 충격시험을 요구하는 경우 철판의 롤링방향은 용접방향과 수직이 되어야 하며 횡 방향(넓이 방향)의 충격시험의 경우는 롤링방향은 용접방향에 평행되어야 함. Ch 12 Sec 2.3.2
대표적인 시험시편은 Fig. 12.2.1 (a) to (c) 을 참조할 것. 이 시험편은 기계적 시험에 필요한 시편들을 채취할 수 있는 최소한의 조건이다. 만약 충격시험이나 그 외 인성시험이 필요하다면, 전체 폭은 용접된 가장 두꺼운 소재의 두께의 8배 이상이 되어야 함.
  • Butt Welding Plate test specimen: See Fig 12.2.1 (a)
  • Butt Welding Pipe test specimen: See Fig 12.2.1 (b)
  • Fillet Welding (Plate): See Fig 12.2.1 (c)
Ch 12 Sec 2.3.3
한 자세 승인은 그 자세에만 허용함

아래보기 하향자세는 별도의 인증시험이 필요함,
최고/최저 입열량 자세로 용접 실시 (D, X, Vu, O)

즉 각각의 자세로 시험 또는 최고/최저 입열량
자세2가지 시험 실시
Ch 12 Sec 2.3.4
검사원은 시편의 용접과 시험편들의 시험들을 관리감독하여야 함. Ch 12 Sec 2.3.5
용접자세에 따른 용접시험편의 위치 - Fig 12.2.2(a) to (d) 참조 :
  • Plate butt weld test positions: Fig. 12.2.2 (a)
  • Pipe butt weld test positions: Fig. 12.2.2 (b)
  • Plate fillet weld test positions: Fig. 12.2.2(c)
  • Pipe fillet weld test positions: Fig. 12.2.2 (d)
Ch 12 Sec 2.3.6
용접 자세 지정 및 기호 ISO나 AWS 기술하는 용접자세들과 동등한 로이드 용접자세 - Table 12.2.1 참조
  • Equivalent designations of welding positions: Table 12.2.1
Ch 12 Sec 2.3.7
2.4용접 용접시험편의 용접은 동의된 사전용접절차서에따라 실시되어야 함. 만약 제품 용접 시 tack 용접 위에 용접이 필요할 경우 시험 편에도 그 용접과 똑같은 조건으로 용접을 해야 함. 또한 그 Tack 용접은 용접 시편 내에 포함되야하고 그 위치가 기록되야함. 수동 및 반자동 용접공정에서, 용접 정지와 재 시작점을 용접시편 내에 포함시킬 것. 필렛용접은 한 면에서만 용접. Ch 12 Sec 2.4
2.5 비파괴시험 용접완료 후 그리고 기계적 시험을 위한 시편가공 전 표면 크랙과 외관검사를 실시함 Ch 12 Sec 2.5.1
맞대기 용접(Butt) 시편은 방사선 검사 또는 초음파 검사 실시. Ch 12 Sec 2.5.2
규정 항복응력400 N/mm2까지 그리고 탄소당량 0.41% 이하의 강(steel) 용접의 경우, 용접 후 주위온도까지 냉각되었을 때 즉시 비파괴 검사를 실시가능. 그 외 다른 종의 강의 경우, 용접 후 시편이 주변 온도까지 냉각된 후 48시간이 지나서 비파괴 검사를 실시. Ch 12 Sec 2.5.4
후열처리가 필요할 경우, 그 후 열처리가 끝난 후에 비파괴검사 실시. Pt 2 Ch 12
Sec 2.15.14
모든 비파괴 검사는 재료 규정의 Chapter 1 Section 5의 규정에 따라서 진행. 그 결과 판정은 ISO 5817 Level B 에 따름. 단 과도한 Convexity 와 Throat 두께는 Level C를 적용. Ch 12 Sec 2.5.5
방사선 검사를 대신하여 초음파 검사를 실시할 수도 있는데 동등한 용접품질로(규정 2.5.5를 적용) 간주될 수 있는 허용범위는 시험실시 전 검사원과 사전협의 및 동의가 필요. 초음파 검사의 두께에 따른 제한 규정은 재료규정의 Chapter 13 Section 2.15.2 볼 것. Ch 12 Sec 2.5.6
검사원과의 사전 협의 및 동의를 전제로 하면서 허용할 수 없는 결함이 부피형(선형이 아닌)이면서 어떤 한 부분에만 위치해 있을 경우, 시험을 (다음 단계로) 계속 할 수도 있으며 그 결함부분을 피하여 파괴 시험편을 채취할 수도 있음. Ch 12 Sec 2.5.8
2.6 파괴 시험 일반규정 용접시험편은 열처리 후에 그리고 필요한 비파괴 시험에 합격했을 때 파괴시험을 위한 시편채취가 가능. Ch 12 Sec 2.6.1
시편들의 치수와 시험조건은 재료규정의 Chapter 2.12 규정에 따름. Ch 12 Sec 2.6.2
합격범위는 이 Chapter의 2.12 규정에 따르며 다른 엄격한 규정이 있을 경우 그에 따름 Ch 12 Sec 2.6.3
2.7 파괴시험 (강의 맞대기 용접) 시험시편 채취는 Fig 12.2.3 혹은 12.2.4에 따름.
a. Butt welds in plate and pipe over 750 mm diameter: Fig. 12.2.3 Butt welds in pipe less than 750 mm diameter: Fig. 12.2.4
Ch 12 Sec 2.7.1
Longitudinal all weld metal 인장시험은 규정 12.2.1 과 12.2.2에 따름. 하나 이상의 다른 종류의 용접봉 혹은 용접방법들이 사용되었을 경우 그 시편은 그 해당부분들에서 각각 채취. 이 조항은 Root 나 First(최초 층의) 용접에는 적용되지 않음. Ch 12 Sec 2.7.2
승인된 용접봉을 사용했을 경우 위의 2.7.2의 시험은 생략가능. Ch 12 Sec 2.7.3
Transverse 인장시험은 규정 Ch 11 Sec 2.1.1 에 따르며 전(Full thickness) 두께로 준비. Ch 12 Sec 2.7.4
Transverse 인장시험 시 그 시편의 파괴에 필요한 최대 Load가 인장 시험기의 용량을 초과하는 경우 몇 개의 시험 편들을 전 두께(Full thickness)에 걸쳐 채취하여 시험가능. Ch 12 Sec 2.7.5
Transverse bend 시험편은 Fig 12.2.5에 따름. 두께가 12mm 이상 되는 경우 Face와 Root bend들이 Side bend 시험으로 대체 가능. 철판면 높이를 초과하는 용접부는 가공 또는 연마하여 제거 할 수도 있으며 시편 가장자리는 시편 두께의 10%를 넘지 않은 Radius로 만곡부를 만들 수도 있음. 각 시험편은 최소 180°각도로 시험. 굽힘시험의 비율은 규정에 따라 정함. 자세한 내용은 규정 참조. Ch 12 Sec 2.7.6
이종 금속 용접 시 금속들 중 낮은 인성치의 금속을 기준으로 규정 2.7.8을 적용. Ch 12 Sec 2.7.7
선체구조용 강인 경우 충격시험편은 Fig 12.2.6 또는 12.2.7에 따라 준비해야 하며 충격시험편의 Notch는 철판표면에 수직되게 함. 또한 충격 시험편은 재료규정의 Chapter 2 Section 3 에 따라 치수 및 시편의 분배를 갖도록 해야 함. 한 종류이상의 용접법 또는 용접봉을 사용했을 경우 상기 기술한 규정 2.7.2를 준용한다. 용접부 두께가 50mm를 초과하는 경우 다른 종류의 용접 방법 또는 용접봉 사용과 관계없이 추가 충격시험편을 Root부에서 Fig 12.2.6과 12.2.7에 따라 채취. Ch 12 Sec 2.7.8
해상구조물 또는 압력용기의 경우 FL + 10mm 위치에서 Notch가 요구되지 않음. 다른 종류의 용접방법들 또는 용접봉들을 사용하였을 경우 상기 기술한 규정 2.7.2를 준용. Ch 12 Sec 2.7.9
최소 한 개의 Macro 검사 시험 시편을 용접이 시작된 시험편의 말단부 근처에서 채취. 시편은 용접부 및 열영향부의 전체 단면을 포함해야 하며 열영향부와 용접수의 각 용접층들을 명확하게 드러낼 수 있도록 준비 및 부식(Etching)할 수 있어야 함.시험은 5배에서 10배사이의 확대 하에서 해야 함. Ch 12 Sec 2.7.10
용접부의 화학분석시험은 Macro시편을 사용하여 실행. 승인된 용접봉을 사용하지 않았을 경우 결과치는 용접봉 제조자 명세에 기술된 제한치와 부합해야 함. Ch 12 Sec 2.7.11
비커스(Vickers)경도 검사는 Fig 12.2.8에 따라 10kg이 넘지 않는 부하(Load)로 시험시편의 용접시작점 말단부에서 채취된 Macro 시험편을 사용하여 시행. 각인들(Indents)의 각각의 열에 대해 최소한 세 개씩의 각인들을 용접부, 열영향부 (양쪽으로) 또는 모재부 (양쪽으로)등에 찍어야 함. 각 각인간 권고거리는 1.0mm이며 최소거리는 ISO 6507/1에 규정된 최소치보다 적어서는 안됨. Ch 12 Sec 2.7.12
2.8강의 Fillet weld- 파괴시험 강의 Fillet weld에 대한 파괴시험 규정에 따름. . Ch 12 Sec 2.8
2.9강의 T.K.Y Nozzle용접- 파괴시험 강의 T.K.Y Nozzle용접에 대한 파괴시험 규정에 따름. Ch 12 Sec 2.9
2.10강의 Pipe의 Branch용접- 파괴시험 강재 Pipe의 Branch용접에 대한 파괴시험 규정에 따름. Ch 12 Sec 2.10
2.11강의 Clad용접- 파괴시험 강의 Clad용접에 대한 파괴시험규정. Ch 12 Sec 2.11
2.12기계적 시험의 합격기준 강의 용접 시 기계적 시험의 합격기준 Ch 12 Sec 2.7.11
Longitudinal all weld metal 인장시험
  • 일반적으로 Table 11.3.2 또는 11.4.2에 규정된 강의 등급 및 용접법에 해당되는 최소 물성치에 맞아야 하며
  • 용접봉 승인이 재료규정의 Chapter 11에 규정되어 있지 않은 경우 Longitudinal all weld 인장시험의 인장강도는 철판의 최소 규정 물성치에 부합해야 함.
  • 탄소 또는 탄소망간강으로 만든 압력용기의 경우 Longitudinal all weld 인장시험은 철판의 최소 규정보다 적으면 안되며 또한 동시에 최소규정강도보다 145N/mm2이 넘으면 안됨.
Ch 12 Sec 2.12.1
Transverse 인장시험 Transverse 인장시험 - 시험결과에 나온 인장강도가 모재의 최소 규정강도보다 적으면 안됨. Ch 12 Sec 2.12.2
Bend 시험 일반적으로 요구되는 Former의 지름상에서 해당각도까지 굽힌 후 인장응력을 받은 시편부의 표면이 어느 방향으로든지 3.0mm가 넘는 결함을 보이지 않아야 함.
  • 압력용기용에 적용하는 굽힘시험의 경우 굽힘 후 시험편의 종 방향으로 측정하여 3.0mm 또는 시험편의 축에 횡 방향으로 측정하여 1.5mm를 넘는 결함을 보이지 않아야 함.
  • 모든 경우 시험편의 모서리에서, 너무 이른 결함의 생성에 따른 굽힘시험의 실패가, 이러한 결함이 용접결함과 관련되어 있지 않은 한, 시험의 불합격의 원인이 되어서는 안됨.
Ch 12 Sec 2.12.3
충격시험 충격시험
  • 선체제작용 충격시험편은 Table 12.7.2에 규정되어 있는 대로 해당온도에서 최소 충격에너지를 만족해야 함.
  • 선체제작용이의 구조물에 적용되는 충격시험편들은 시험에 사용된 모재의 규정물성치에 따라 같은 온도에서 시험하여 같은 최소 충격에너지를 만족해야 함.
  • 특정구조물제작에 해당하는 규정에서 요구하지 않는 한 충격시험의 합격기준은 위에서 기술한 바와 같음.
  • Quenching & Tempered 철판의 경우 요구되는 시험온도 및 충격에너지는 모재에서 요구되는 규정물성치에 따름.
Ch 12 Sec 2.12.4
Macro 시험검사 Macro 시험검사 Macro 단면은 모재와 부드럽게 혼합된 균등한 용접면을 보여야 함. Ch 12 Sec 2.12.5
경도시험 최대경도치는 강의 경우 규정 최소 인장강도가 350N/mm2 이하면 350Hv, 420 N/mm2에서 690 N/mm2 범위에서는 420Hv을 넘어서는 안됨. Ch 12 Sec 2.12.6
용접부의 파단 혹은 파괴시험규정 용접부 파단 혹은 파괴시험규정에 따름. Ch 12 Sec 2.12.7
2.13불합격 (재시험) 규정 불합격 (재시험) 규정에 따름 Ch 12 Sec 2.13

시험기록

  • 절차인증기록(PQR)은 제조자가 준비하여 상기 2.2항에서 기술한대로 시험시 사용한 조건의 상세를 포함해야 합니다.
  • 위의 PQR에 관련된 모든 용접변수의 상세가 기술되어 있고 그 내용이 일관되며 시험결과가 규정에 부합하는 경우 검사원은 그 해당 PQR이 규정을 만족하는 것으로 이서할 수도 있습니다.

승인범위

  • 규정에 따라 성공적으로 끝난 용접인증시험은 시험중 사용한 시험편의 용접 보다 더 넓게 적용할 수 있음
  • 아래의 범위를 벗어나는 경우 새로운 인증시험 실시
  • 이 항에서 기술 안된 변수들의 승인범위들은 검사원과 합의할 수도 있으나 단, 인정된 국가나 세계적 표준에 따른 경우에 한함
제목 요약 내용 관련 규정
제조자 한 제조자의 인증 받은 용접절차는 동일한 기술과 품질관리가 되는 그 제조자의 공장들에 유효함. Ch 12 Sec 2.15.4
용접 방법 및 기법 인증시험에서 사용된 것에 한함 Ch 12 Sec 2.15.5
용접 자세 한 자세 승인은 그 자세에만 허용함. Ch 12 Sec 2.15.6
제조자 한 자세 승인은 그 자세에만 허용함

아래보기 하향자세는 별도의 인증시험이 필요함,
최고/최저 입열량 자세로 용접 실시 (D, X, Vu, O)

즉 각각의 자세로 시험 또는 최고/최저 입열량
자세2가지 시험 실시
Ch 12 Sec 2.3.4
이음매형상 Butt(맞대기)용접 수행 시 Fillet 및 Partial Penetration 용접까지 승인 될 수도 있음.
다른 형태의 Butt 용접시 이음매에 따른 승인 범위는 Table 12.2.3 을 참조.
Ch 12 Sec 2.15.7
Table 12.2.3
소재 종류
  • 어떤 특정 강도 수준 강을 사용하여 이행된 용접인증 시험은 규정된 같거나 낮은 최소 항복응력을 가진 유사한 소재 용접에 사용할 수도 있음. 단, 고입열량 용접(A) 이나 Two-run(T)용접 경우는 그 인증 시험에 사용된 강도수준에서만 사용이 가능. 비슷하게, 어떤 특정 인성 강도 수준의 강을 이용한 용접인증 시험은 같거나 세 단계 아래의 최소인성을 가진 유사한 소재의 용접에 사용할 수도 있음.
  • 고강도의 Quenching/Tempering (이하 QT) 소재의 경우 각각의 강도수준에서 볼 때 시험된 용접절차는 같거나 더 낮은 인성 강도의 경우에 사용할 수 있음.각각의 인성강도 면에서 볼때 시험된 용접절차는 같거나 더 낮은 강도의 경우에 사용될 수 있음. TMCP강은 QT강의 승인과 별도로 승인을 받아야 하며 그 반대로 TMCP강의 승인을 받았다 하더라도 QT강은 추가 승인을 받아야 함.
  • 용접이 가능한 C and C-Mn 단조품 소재의 경우 시험된 용접절차는 같거나 더 낮은 인성강도 수준에 사용될 수 있음. 단 QT 단조강의 경우 다른 방식으로 열처리된 단 조강에 사용할 수 없으며 그 반대의 경우도 같음.
  • 용접이 가능한 C and C-Mn 주조품 소재의 경우 시험된 용접절차는 같거나 더 낮은 인성강도 수준의 주강에 사용될 수 있음. 단 QT 주강의 경우 다른 종류의 열처리된 주강에 사용할 수 없으며 그 반대의 경우도 같음
  • 용접절차 인증시험이 이종소재로 이루어졌을 경우 그 시험에 사용된 소재로만 인증이 제한.
Ch 12 Sec 2.15.8
Table 12.2.3
두께/직경
  • 일반적인 맞대기 용접의 경우 시험시편의 두께와 용접형상에 따라 달라짐. Table 12.2.4 를 참조
  • 각기 다른 두께의 맞대기 용접 시 두께가 작은 쪽이 기준이 됨.
  • Fillet 및 T형 맞대기 용접 시: Table 12.2.4는 인접하고 관통하는 모재에도 해당됨. 12. 2. 4의 규정에 추가하여 Fillet용접시 각목(throat)에 대한 승인 범위는 다음과 같음.

    Fillet 용접 시: Single run 각목 0.75a to 1.5a,
    Multi run 각목 (a=t 즉 맞대기 용접의 경우와 같음),
    a: 각목, t: 두께

  • 위 규정에도 불구하고 만약 만약 HAZ부에서 3개의 경도 값이 최대 허용치를 넘어 25Hv 내 일 때는 두께승인 범위는 시험시 사용된 두께로 제한.
  • 두께승인 범위: Table 12.2.4 를 참조.
  • 직경승인 범위: 시험편의 외경과 용접형상에 따라 다르며 Table 12.2.5에 따름.
Ch 12 Sec 2.15.9
Table 12.2.4/12.2.5
용접봉
  • 중간 용입과 마무리 용접을 위해 사용되는 수동 및 반자동 용접의 경우, 용접 인증 시험에 사용된 용접봉이나 용접 와이어의 제품이름이나 상표의 변경이 가능하나 단, 변경될 제품이 같거나 더 높은 등급의 승인 품이며 Flux type (예. basic low hydrogen, rutile, etc)은 동일한 제품이 되어야 함.
  • One Side 완전 용입 맞대기 용접에서 루트부를 만드는 용접봉의 경우 그 시험에 사용했던 용접봉 제품의 상표, 형식 또는 Backing 소재의 변경은 허용되지 않음.
  • 입열량이 5kJ/mm 이상인 용접법 경우, 용접봉 의 형식과 상표 변경은 허용되지 않음.
Ch 12 Sec 2.15.10
쉴드(차폐) 가스 용접 절차 인증시험에 사용되었던 차폐가스 사용 변경은 새로운 시험을 시행해야 함. Ch 12 Sec 2.15.11
입열량 입열량 범위의 상한치는 인증 시험에서 사용했던 입열량보다 25% 큰값 이나 5.5kJ/mm중에서 작은 값으로 한다. 입열량이 5.0kJ/mm을 넘을 경우, 그때의 상한치는 시험 때의 입열량보다 10% 큰 값으로 한다. 모든 경우에 입열량 승인의 하한치는 성능 시험시의 입열량보다 25% 낮은 값으로 한다.

입열량 계산식 : HI =(Voltage x Amperage x 60)/ (1000 x Travel speed mm/min) KJ/mm2
Ch 12 Sec 2.15.12
전류 형태 시험에 사용된 전류형식만 허용 Ch 12 Sec 2.15.13
예열 온도 시험에 사용된 온도가 승인 최소온도, 최대는 최대층간 온도, 단, 경도시험 결과 최대허용치에 근접할 경우 시험한 시편보다 두꺼운 소재를 용접할 때는 예열 온도를 높여야 함. Ch 12 Sec 2.15.14
층간온도 시험 시 기록된 최대 층간 온도가 최대허용온도, 실제 생산 시 낮은 온도를 규정할 수 있으나 예열 온도보다는 높게해야함. Ch 12 Sec 2.15.15
후열처리 어떤 시험이라도 시험 시 후열처리 적용했을 땐 용접 시 반드시 후열처리 실시.

열처리 없는 인증시험은 열처리 없는 용접에만 사용할 수 있으며 그 반대의 경우도 똑같이 적용됨.

허용할 수 있는 평균 열처리 온도 변화는 시험 시 사용된 온도에서 25 °C까지 임.
Pt 2 Ch 12 Sec
2.15.16
Shop Primers Shop Primer 를 칠하고 인증되었을 경우 칠하지 않은 경우까지 승인함. 그러나 그 반대는 허용하지 않음. Pt 2 Ch 12 Sec
2.15.16

용접사 자격 인증 시험

  • 일반 규정
    • 이항의 규정은 선박 또는 기타 해상 구조물, 또한 그 선박 또는 구조물에 설치 사용될 제품 및 장비류들과 관련된 용접된 구조물에 관련된 용접사들의 자격 인증에 관한 것입니다
    • 이 규정은 수동, 반자동 또는 부분 기계화된 용융 용접 방법과 관련이 있습니다. 이 규정을 바탕으로 채택된 다른 용접 공정은 특별히 고려될 수 있습니다.
    • 제품 용접을 시작하기 전, 용접사는 이 규정들에 만족하는 자격 인증 시험을 실시해야만 합니다. 용접사가 수행할 작업에 필요한 수준의 기능을 갖고 있음을 보증하는 것은 제조자의 책임입니다.
    • 용접사의 자격은 제조자에 의해 문서화 되어야 하고 그 기록들은 검사원이 검토할 수 있어야 합니다.
    • EN, ISO, JIS, ASME 또는 AWS에 따라 행해진 용접사 인증 시험들을 인정할 수 있는 경우가 있는데 단, 그 경우 최소한, 그 시험들이 이 규정의 기술적인 취지에 동등하거나 부합해야 함을 담당검사원이 확인 및 인정할 수 있어야 합니다.
    제목 요약 내용 관련 규정
    5.2 용접사 인증시험용 시험편 용접은 생산작업에 경험할 수 있는 조건들을 최대한 실제적으로 구현하여야 하며 검사원의 입회 하에 진행. 시험은 생산작업의 일부분으로 해서는 안되며 시험편을 사용해서 시행. Ch 12 Sec 5.2.1
    시험은 최대한 실제적으로 생산작업 시 해야 되는 용접기술과 용접숙련도를 구현. 용접시험편은 용접사의 기능을 시험할 수 있도록 입안되어 필요한 승인범위에 적합한 치수와 모양을 가질 것. Ch 12 Sec 5.2.2
    시험할 용접부의 검사할 용접부 길이는 모든 필요한 시험 시편들을 채취할 수 있게끔 해야 하며 철판의 경우 250mm이상이 되어야 함. 용접편은 승인받을 자세에 적절한, Fig 12.2.2에 규정되어있는 자세들 중 하나로 고정되어야 함. Ch 12 Sec 5.2.3
    승인 받는 용접절차(WPS)가 요구되며 최소한 2.2.1에 규정되어 있는 정보를 포함할 것. h 12 Sec 5.2.4
    시험편은 고유 식별번호를 타각하여야 하며 검사에 필요한 용접길이가 용접 전 미리 표식이 되어야 함. 관(Pipe)용접의 경우 전체 둘레가 검사부위로 간주됨. Ch 12 Sec 5.2.5
    시험편 용접 시 용접시간은 실제 생산조건 하에서 예상하는 시간과 비슷해야 함. 수동 또는 반자동 용접의 경우 적어도 Root부와 표면 최종용접 층에서 한 개의 용접점지점과 최종용접점이 용접부 검사부위에 포함되어야 하며 나중의 검사를 위해 표식이 되어야 함. Ch 12 Sec 5.2.6
    용접 중 용접사는 용접부 표면의 최종 용접층을 제외하고 작은 결함들은 실제 생산 시 사용하는 방법으로 제거 할 수도 있음. Ch 12 Sec 5.2.7
    검사원은 용접 시험조건이 정확하지 않을 경우 또는 요구되는 기준을 갖춰야 하는 용접사의 기량에 대해 의문이 있는 경우, 용접시험의 중지가 가능. Ch 12 Sec 5.2.8
    5.3 검사 및 시험 검사 및 시험 Ch 12 Sec 5.3
    각각의 완료된 용접은 Table 12.5.1에 따라 검사하고 시험. Ch 12 Sec 5.3.1
    외관검사는 용접된 상태에서 다른 시험보다 먼저 실행. Ch 12 Sec 5.3.2
    철판 맞대기 용접의 경우 파괴시험을 방사선 투과검사 대신 실행. Ch 12 Sec 5.3.3
    받침(Backing strip)을 사용한 경우 비파괴검사 시에는 그대로 놔두어야 되지만 굽힘이나 파괴 시험 실시 전에는 제거. Ch 12 Sec 5.3.4
    Filet용접의 파괴시험일 경우 규정을 참조. Ch 12 Sec 5.3.5
    알루미늄 합금의 맞대기 용접의 경우 방사선 투과검사 및 굽힘시험이 요구. Ch 12 Sec 5.3.6
    굽힘 시험의 경우 2개의 Root bends와 2개의 Face bends를 시험해야 하며 시험편 두께가 12mm가 넘은 경우 4개의 Side bend 시험편을 대체 가능. 사용될 Former의 지름은 2.7.6(a)에 있는 WPS 시험의 규정에 따름. Ch 12 Sec 5.3.7
    Macro 시편이 필요한 경우 시험편은 곱게 연마하여 용접층에 열영향부가 잘 나타나게끔 부식되어야 하며 5배와 10배 배율 확대 하에 검사를 해야함. Ch 12 Sec 5.3.8
    5.4 합격기준 합격기준 Ch 12 Sec 5.4
    합격기준은 규정 2.5.5에 따른다 Ch 12 Sec 5.4.1
    파괴시험 및 Macro 단면검사는 비파괴시험의 Acceptance Criteria 에 따라 평가한다 Ch 12 Sec 5.4.2
    굽힘시험의 경우 180° 각으로 굽힌 후 인장을 받는 면에서 볼 때 어느 방향에서든 3mm가 넘지 않은 결함은 허용. Ch 12 Sec 5.4.3
    5.5 불합격 불합격기준 Ch 12 Sec 5.5
    Macro시험의 경우 용접시험편에서 한 개의 추가 시험시편을 채취하여 검사. Ch 12 Sec 5.5.1
    굽힘이나 파괴시험의 경우 2개의 추가 시험시편들은 같은 용접시험편에서 채취하여 시험가능. 시험시편채취가 불가능할 경우 검사원 고려하에 같은 WPS를 사용하여 추가 용접 가능. Ch 12 Sec 5.5.2
    추가시험에 불합격 시 시험은 불합격 된 것으로 간주 가능 Ch 12 Sec 5.5.3
    불합격 시 2차시험이 허용되나 다시 불합격 시 그 용접사는 규정을 맞출 수 있는 능력이 없는 것으로 간주. Ch 12 Sec 5.5.4
    5.6 용접사 자격 승인 범위 모든 필요한 검사 및 시험이 성공적으로 끝났을 때 그 용접사는 자격이 인증된 것으로 간주. 용접사승인에 필요한 용접조건의 범위와 용접 시 필수 변수들은 다음과 같음 Ch 12 Sec 5.6.1
    예열, 층간온도, 입열량, 전류형태 같은 용접변수들은 용접사 자격인증의 변수들로써 고려하지 않음. 그러나 만약 시험에 사용된 WPS에 이러한 변수들이 언급되어 있다면, 이 변수들도 용접사 시험에 포함 되야 하고, 용접사는 이런 특정한 지침을 따르는 것이 필요. Ch 12 Sec 5.6.2
    자격 시험에 사용된 WPS가 후열처리를 언급하고 있는 경우, 굽힘시험이 필요하지 않거나 용접한 상태에서 소재가 낮은 연성을 보이지 않는다면 후열처리를 시험용접에 적용할 필요는 없음. Ch 12 Sec 5.6.3
    제조업체에 의해 수행된 자격인증시험은 그 시험 중에 사용했던 것과 똑같은 품질 시스템과 기술적인 관리하에 있는 작업장에만 적용. Ch 12 Sec 5.6.4
    자격인증 시험에서 사용된 용접방법이 곧 승인된 용접방법. 그러나 용접사가 시험에서 한 용접방법들을 사용하는 것이 가능하며 각각의 용접방법에 적용될 수도 있는 승인 범위는 각각의 용접 방법을 사용한 용접시험에 해당되는 용접 필수 변수의 허용 한계 내에서 가능. Ch 12 Sec 5.6.5
    소재 종류는 용접사 인증에 쓰이는 Table 12.5.2에 나와 있는 대로 그룹으로 분류. 한 그룹에서 한가지 소재로 수행된 자격 자격인증 시험은 같은 그룹 내에 있는 다른 소재의 용접도 허용. 추가로, 소재 중 한 그룹에 대한 자격인증은Table 12.5.3에 있는 대로 다른 그룹의 용접의 승인도 허용. Ch 12 Sec 5.6.6
    하나의 두께에 대해 수행된 자격 인증시험은Table 12.5.4. 에 나와있는 대로 다른 두께들의 용접에 승인. 각기 다른 두께를 가진 소재의 용접이 필요 할 경우, 승인 목적을 위해 참고 기준이 되는 두께는 둘 중 낮은 두께가 됨. Ch 12 Sec 5.6.7
    철판에 대한 용접사 자격 인증시험은 고정된 위치에서 500mm보다 큰 외경을 가진 파이프에 용접을 승인. (See Table 12.5.5 and Table 12.5.6). Ch 12 Sec 5.6.8
    특정 직경의 파이프에 실행된 인증시험은 Table 12.5.5에 나와있는 대로 다른 직경들의 파이프 용접을 승인. (See Table 12.5.5 and Table 12.5.6). Ch 12 Sec 5.6.9
    맞대기 용접으로 실행된 인증시험은 필렛용접의 승인을 허용. Ch 12 Sec 5.6.10
    루트에 받침 없는 (즉 No Backing)맞대기 한면 용접으로 실행된 인증시험은 양면용접까지 허용. 단, 그 반대의 경우는 허용 않음. Ch 12 Sec 5.6.11
    한 자세로 실행된 인증시험은 Table 12.5.6에 나와있는 대로 다른 자세들도 승인. Ch 12 Sec 5.6.12
    피복용접봉을 사용한 수동 Metal Arc 용접의 경우, 한 종류의 피복아크 용접봉이 사용된 인증시험은 그 피복을 사용한 용접만을 승인. Ch 12 Sec 5.6.13
    한 종류의 가스만을 사용한 가스 차폐 용접법들의 경우 시험에 사용된 가스 성분의 변경을 허용치 않음. 시험 시 두 가지 성분의 차폐가스를 사용한 경우, 가스 성분들의 함량 변경은 허용. 단, 그 변화가 차폐가스를 활성화에서 불활성으로 변경시키지 않는 조건에서 이며 그 반대의 경우에도 해당. Ch 12 Sec 5.6.14
    용가제의 변경은 허용. Ch 12 Sec 5.6.15
    5.7 용접사 자격 인증 인증 시험 중 사용된 모든 관련한 조건들은 허용된 승인 범위들과 함께 용접사 승인 증서에 기입되어야 함. Ch 12 Sec 5.7.2
    용접사는 최초 2년간 승인된 것으로 간주. 제조업체는 용접사가 증서 취득 후 6개월 동안 인정할만한 용접실적으로 용접공정을 운영하고 있다는 것을 확인하고, 매 6개월 마다 이런 품질을 유지하도록 해야함. Ch 12 Sec 5.7.3
    2년후, 6개월을 초과하지 않고, 원래의 승인 범위 내에서, 인정할만한 용접실적을 확인할 수 있는 기록 또는 문서화된 검증 자료가 있다면 검사원은 또 다른 2년간의 기간 동안 승인을 연장토록 합니다. 검사관은 그 증서에 유효기간을 연장하는 내용으로 문서화합니다. Ch 12 Sec 5.7.4
    용접사의 능력을 의심할만한 이유가 있는 경우, 용접법에 사용에 연속성이 부족한 경우, 또는 인정할 만한 용접실적의 기록된 증거가 부족한 경우, 용접사는 재자격인증시험을 실행하여야 합니다. Ch 12 Sec 5.7.5
    제조자에게 이전에 자격인증시험을 실시한 기존 용접사들이 있는 경우 다음의 경우 인정하는 것으로 간주될 수도 있습니다. 즉 그 용접사들이 상기 요건들을 만족하며 그 자격인증 시험들이 로이드 선급이 인정할 수 있는 독자적인 시험 기관의 입회하에 실시되어야 합니다. Ch 12 Sec 5.7.6
    위의 모든 규정에도 불구하고 검사원은 언제든지 용접사 자격인증기록들의 검토를 요구할 수 있습니다. 용접사의 기능에 관해 의문을 가질 만한 이유가 있는 경우 검사원은 자격인증을 회수하고 재 인증시험의 실행을 요구할 수도 있습니다. Ch 12 Sec 5.7.7


주)
1.본 한글판은 고객의 편의를 위해 임의적으로 번역한 것이며 정확한 해석은 같이 첨부되어 있는 영문판이 우선합니다.

2.상기규정은 사전예고없이 바뀔 수 있으므로 반드시 변경내용의 확인은 최신규정집을 참고하시거나 가까운 로이드 선급
  사무실로 문의하시기 바랍니다.

Welding Qualifications General qualification requirements

  • General
    • This Section applies to all welding qualifications and tests required to be performed in the course of new construction, conversions, modifications or repairs made on ships, other marine structures and their associated pressure vessels, machinery and equipment.
    • These Rules also apply to all welding work related to other applications for which Lloyd’s Register (hereinafter referred to as LR) have issued Rules or have an interest.
    • It is the responsibility of the manufacturer to ensure compliance with all aspects of these Rules. All deviations are to be recorded as non-compliances and brought to the attention of the Surveyor along with the corrective actions taken. Failure to do this is considered to render the welding tests as not complying with the Rules.
    • Welding tests are to be performed under survey at the manufacturer’s works. Welding procedure qualification tests and welder qualifications tests are to be performed and approved prior to commencement of fabrication or construction.
    • Weld procedure tests made in accordance with EN, ISO, JIS, ASME or AWS may be considered for acceptance provided that, as a minimum, they are equivalent to and meet the technical intent of these Rules to the satisfaction of the Surveyor.
    • Welding tests that have previously been carried out may be considered for acceptance, provided that they have been supervised by an independent body acceptable to LR and the Surveyor is satisfied with the authenticity of such tests.
    • The responsibility for the performance of the weld tests rests with the manufacturer. Aspects of the welding tests, such as mechanical testing, non-destructive testing and heat treatment, may be subcontracted by the manufacturer provided that the subcontractor performs the work under the technical control and direction of the manufacturer, and this is agreed with the Surveyor prior to commencing the work.
    • In these Rules, the term ‘manufacturer’ considered to include any firm or organisation that performs welding and is considered to be the shipbuilder, or construction firm, or fabricator, or material manufacturer.
  • Design
    • Welding procedure qualification tests are required to give assurance that construction welds made in accordance with the approved plans or the approved design have acceptable properties. It is the manufacturer’s responsibility to establish and document whether a procedure is suitable for a particular application.
    • The requirements relate to mechanical properties of the weld and heat affected zone, however, other tests may be required on certain materials, for example, corrosion or fatigue tests, in order to ensure suitability for the proposed application.
  • Materials
    • Materials used for testing are to be of the same grade, type and from the same manufacturing process as those to be used for construction, unless prior agreement is obtained from the Surveyor. Such agreements will only apply on a case-by-case basis.
    • All materials used for testing are to be suitably marked and identifiable to the original manufacturer’s material certificate.
  • Performance of welding tests
    • All welding and subsequent testing is to be performed in accordance with the requirements of this Chapter.
    • The manufacturer is responsible for monitoring the tests and for recording all the welding variables as specified in 2.2 and for compiling all the non-destructive examination (NDE) reports and mechanical test records for submission to the Surveyor.
    • The laboratory or testing establishment used to perform the tests is to have the necessary equipment, maintained in good order and suitably calibrated. The Surveyor is to be satisfied that the laboratory personnel have the appropriate skills and are appropriately qualified in accordance with Ch 2,1.2.1.

Section 2 Welding Procedure Qualification Tests for Steels

  • General
    • The requirements of this Section relate to welding procedure test requirements of carbon, carbon-manganese steels and low alloys steels. Additional requirements for austenitic and austenitic/ferritic duplex stainless steels, aluminium and copper alloys are specified in Sections 3 and 4 respectively.
    • Prior to performing the welding procedure qualification test, the manufacturer is to present to the Surveyor a preliminary Welding Procedure Specification (pWPS) detailing the welding processes, positions, joint types, materials and heat treatments to be performed during the test. The pWPS is to be presented for information prior to commencing the test.
    • The type and extent of testing to be applied to each welding procedure test is to be in accordance with subsequent Sections of this Chapter.
    • For the welding procedure approval, the welding procedure qualification tests given in this Section are to be carried out with satisfactory results. Welding procedure specifications are to refer to the test results achieved during welding procedure qualification testing.
  • Welding variables
    • In order that the conditions of the qualification test may be applied to production welding operations, the appropriate variables are to be recorded by the manufacturer during welding and testing from the following list:

      (a). The unique qualification reference number and the date of welding;

      (b). The material type, grade, product form, dimensions and identification;

      (c). Welding process(es), including tack welds;

      (d). Joint type, dimensions and surface condition;

      (e). Welding position(s);

      (f). Welding technique(s), weaving, multiple electrodes, etc;

      (g). Welding consumables including fluxes, shielding gases, etc;

      (h). Control of consumables, baking or drying conditions, etc;

      (i). Welding parameters, current, voltages, travel speeds, etc;

      (j). Number and sequence of weld runs;

      (k). Backing materials including any backing gas;

      (l). Preheats and interpass temperatures;

      (m). Methods used for cleaning and inspection of root deposits;

      (n). Post-weld heat treatment, temperature and cycle times;

      (o). Special weld profiling requirements.
    • Other variables may need to be recorded depending on the particular welding process or application and are to be agreed with the Surveyor, for example the peak and base current and cycle times for pulse welding, electrode type and nozzle size for GTAW welding, etc.
  • Steel test assemblies
    • Tests are to be performed using the welding process and positions anticipated for actual construction. The weld test assemblies are to be representative of construction conditions and are to be welded in the same manner as intended for the actual production welds. Where prefabrication primers are used in the shipyard, these are to be included in the test assemblies.
    • For plate tests, the direction of plate rolling relative to the weld direction is to be considered. Where the material used for the test requires longitudinal impact tests, the plate rolling direction is to be perpendicular to the weld direction and for material which requires impact testing in the transverse direction, the rolling direction is to be parallel to the weld direction.
    • Typical test assemblies are shown in Fig. 12.2.1(a) to (c). These are a minimum requirement to permit the removal of all the necessary mechanical test specimens. Where impact tests or other toughness tests are required, the total width is not to be less than 8 times the material thickness of the thicker material being joined.

      Fig. 12.2.1.a Butt weld test assembly in plate

      Fig. 12.2.1.b Butt weld test assembly in pipe

      Fig. 12.2.1.c Fillet weld test assembly in plate

    • Welding procedure test assemblies are to be welded separately from production welds and are to be marked with the unique test identification number. The individual pieces of the test assembly may be held together to maintain their relative joint conditions by means of suitable tack welds, clamps or strongbacks.
    • Welding of the test assemblies and testing of test specimens is to be monitored by the Surveyor.
    • The test assembly is to be placed in one of the welding positions shown in Fig. 12.2.2(a) to (d), as specified in the test Welding Procedure Specification (pWPS) and the specified level of preheat applied prior to the start of welding.

      Fig. 12.2.2.a Plate butt weld test positions

      Fig. 12.2.2.b Pipe butt weld test positions

      Fig. 12.2.2.c Plate fillet weld test positions

      Fig. 12.2.2.d Pipe fillet weld test positions

    • Designations for equivalent welding positions shown by different standards are shown in Table 12.2.1.

      Table 12.2.1 Equivalent designations of welding positions
  • Welding of steel test assemblies
    • Welding of the test assembly is to be carried out in accordance with the agreed pWPS. Where, during the progress of the test, it is found necessary to change the conditions specified on the pWPS, this is to be brought to the attention of the Surveyor. If agreed, the test may be permitted to continue with the new conditions and these are to be recorded.
    • Where the production work requires welding over tack welds, the test is to simulate this condition and the tack welds are to be included in the inspection length of the test weld and their position recorded.
    • For manual and semi-automatic welding processes, weld stops and re-starts are to be included in the inspection length of the test weld.
    • Fillet weld test assemblies are welded on one side only.
    • Where the construction welding is predominately fillet welding, in addition to the butt weld qualification test, a fillet weld qualification test is to be performed to confirm that acceptable weld quality is achieved.
  • Non-destructive examination (NDE)
    • On completion of welding, prior to sectioning for mechanical tests, the inspection length of the test assembly is to be subjected to both visual examination and surface crack detection.
    • Butt weld assemblies are also to be subjected to radiographic or ultrasonic examination over the whole inspection length of the weld.
    • For welds in steels with specified yield strength up to 400 N/mm2, and with carbon equivalent less than or equal to 0,41 per cent, NDE may be performed as soon as the test assembly has cooled to ambient temperature. For other steels, NDE is to be delayed for a period of at least 48 hours after the test assembly has cooled to ambient temperature.
    • Where post-weld heat treatment is required, NDE is to be performed after the heat treatment is complete.
    • All NDEs are to be carried out in accordance with the requirements of Ch 1,5. Assessment of results is to be in accordance with ISO 5817 Level B except for excess convexity and excess throat thickness where Level C will apply. Linear porosity is not permitted.
    • As an alternative to radiography, ultrasonic examination may be carried out and acceptance criteria that are considered to result in equivalent weld quality (in accordance with 2.5.5) are to be agreed, with the Surveyor, prior to the tests being carried out. Ultrasonic testing will be subject to the thickness limitation specified in Ch 13,2.12.5.
    • Where the test assembly does not satisfy the nondestructive examination acceptance criteria, the test is to be rejected. A duplicate test assembly may be welded using the original welding conditions. If this fails NDE, the welding procedure is to be considered as incapable of achieving the requirements without modification.
    • Subject to prior agreement with the Surveyor, where unacceptable imperfections are of a volumetric nature and are localised in one small area of the test assembly, the test may be permitted to continue and specimens for destructive testing may be removed, avoiding this area.
  • Destructive tests General requirements
    • The weld test assembly may only be sectioned for destructive testing after any heat treatment and the required non-destructive examinations have been completed successfully.
    • The dimensions of the test specimens and testing conditions are to be in accordance with the requirements specified in Chapter 2.
    • The results of destructive tests are to be assessed in accordance with the acceptance criteria specified in 2.12, unless other, more stringent requirements are specified for the application.
    • Where a weld test is made between materials of different grades, the acceptance criteria that are to be applied are those applicable to the lower grade material.
  • Destructive tests for steel butt welds
    • The test assembly is to be sectioned for mechanical testing in accordance with Figs.12.2.3 or 12.2.4.

      Fig. 12.2.3 Butt welds in plate and pipe over 750 mm diameter

      Fig. 12.2.4 Butt welds in pipe less than 750 mm diameter

    • The longitudinal all weld metal tensile test specimen is to be of circular cross-section as detailed in Ch 11,2.1 and Ch 11,2.1.1. Where more than one welding process or type of consumable has been used to make the weld, test specimens are to be removed from each respective area of the weld. This does not apply to the process or consumables used to make the root or first weld run. During the test, the yield or proof stress, ultimate tensile strength, and elongation to failure are to be recorded.
    • Where approved welding consumables have been used, the longitudinal all weld metal tensile test may be omitted.
    • The transverse tensile test specimen is to be of full thickness with the dimensions shown in Ch 11,2.1.1. The tensile strength and fracture locations are to be reported.
    • Where the maximum load required to fracture the transverse tensile specimen is likely to exceed the capacity of the tensile testing equipment, several tensile specimens may be removed through the thickness and tested. Specimens are to be prepared such that they overlap in the thickness direction so that the full plate thickness is tested.
    • Transverse bend specimens of rectangular section are to be prepared with the weld centred in the middle of the specimen as shown in Fig. 12.2.5. For material of thickness 12 mm or greater, the face and root bends may be substituted by side bend tests. The weld reinforcement may be removed by grinding or machining prior to testing and the edges rounded to a radius not exceeding 10 per cent of the specimen thickness. Each specimen is to be bent through an angle of at least 180°. The bend test ratio is to be the lesser of the following:

      (a).

      Df = (D/t) + 1

      or

      (b).

      Df = 100/Em (rounded up to the next whole number)
      where
      Df = is the bend test ratio
      (D/t) = is the value from Tables 11.3.3, 11.4.3 or 11.8.2, as appropriate
      Em = is the minimum specified percentage elongation for the test material (based on a proportional gauge length of

    • Where the weld test is made between different material types, the requirements of 2.7.8 are to be applied to the material with the lower toughness specification.

      Fig. 12.2.5 Transverse bend test specimens

    • For hull structural steels, impact test specimens are to be prepared from the locations shown in Figs. 12.2.6 or 12.2.7, with the notch perpendicular to the plate surface and have the dimensions and proportions in accordance with Ch 2,3. Where more than one welding process or type of consumable has been used to make the weld, test specimens are also to be removed from these respective parts of the weld. Note that this does not apply to the welding process or consumables used solely to make the root or first weld run. Where the weld thickness exceeds 50 mm, an additional set of impact tests is required from the root area of the weld irrespective or whether different welding process or welding consumables are used as shown in
      Figs. 12.2.6 and 12.2.7. Fig. 12.2.6 Locations of V-notch for butt weld of normal heat input (heat input ≤ 50 kJ/cm)

      Fig. 12.2.7 Locations of V-notch for butt weld of high heat input (heat input > 50 kJ/cm)

    • For offshore structures and pressure vessels, impact test specimens are not required to be notched at the FL + 10 mm location. Where more than one welding process or type of consumable has been used to make the weld, test specimens are to be removed from the respective areas of the weld. This does not apply to the process or consumables used solely to make the root or first weld run.
    • At least one macro examination specimen is to be removed from the test plate, near the end where welding started. The specimen is to include the complete cross-section of the weld and the heat affected zone and be prepared and etched to clearly reveal the weld runs and the heat affected zone. Examination is to be performed under a magnification of between x5 and x10.
    • A chemical analysis of the weld metal is to be performed on the macro specimen where approved welding consumables have not been used. The results are to comply with the limits given in the welding consumable specification.
    • A Vickers hardness survey is to be performed on the macro specimen taken from the weld start end of the test assembly in accordance with that shown in Fig. 12.2.8, using a test load not in excess of 10 kg. For each row of indents, there are to be a minimum of 3 individual indentations in the weld metal, the heat affected zones (both sides) and the base metal (both sides). The recommended distance between indents is 1,0 mm, but the distance between indents should not be less than the minimum specified in ISO 6507/1.

      Fig. 12.2.8 Hardness testing locations for butt welds
  • Destructive tests for steel fillet welds
    • Fillet weld test assemblies are to be sectioned for destructive testing in accordance with Fig. 12.2.1(c) and as follows: (a)two fracture tests;
      (b)three macro-sections;
      (c)one hardness survey.
    • Two fracture test specimens are to be removed from the test weld and are to be subjected to testing by bending the upright plate onto the through plate to produce fracture, as shown in Fig. 12.2.1(c).
    • At least three macro examination specimens are to be removed from the test plate. The specimens are to include the complete cross-section of the weld and the heat affected zone and is to be prepared to clearly reveal the weld runs and the heat affected zone. One of the specimens is to include a weld stop/start position. Examination is to be performed under a magnification of between x5 and x10.
    • A Vickers hardness survey is to be performed on the macro specimen taken from the weld start end of the test assembly in accordance with that shown in Fig. 12.2.9, using a test load not exceeding 10 kg.

      Fig. 12.2.9 Hardness test locations for fillet welds
  • Destructive tests for T, K, Y steel nozzle welds
    • Full penetration ‘T’, ‘K’ and ‘Y’ joints for structural applications and nozzle welds for pressure vessels are to be sectioned for testing in accordance with Fig. 12.2.10 and tested as detailed below:
      (a). three macro specimens;
      (b). impact tests from the weld, fusion line and fusion line + 2 (where the material thickness permits);
      (c). one hardness survey.
      In addition, butt weld tests are to be performed in accordance with 2.7, using the same welding conditions, in order to verify acceptable weld and heat affected zone properties.
    • The impact tests are to be removed from the vertical (up) position ‘B’ in Fig. 12.2.10 and tested in accordance with 2.7.8.

      Fig. 12.2.10 Location of macro-examination test specimens for T, K and Y joints

    • A Vickers hardness survey is to be performed on the macro-section removed from position ‘A’ or ‘C’ in accordance with that shown in Fig. 12.2.11 using a test load not exceeding 10 kg.

      Fig. 12.2.11 Hardness test locations for T, K and Y joints
  • Destructive tests for steel pipe branch welds
    • Pipe branch welds may be by either full penetration, partial penetration or fillet welded, depending on the application and the approved plans. Where these types of welded joints are used, tests are to be performed which simulate the construction conditions.
    • The test weld assembly is to simulate the smallest angle between the branch and main pipe and is to be subjected to macro-examination and hardness testing, as follows:
      (a). For a branch weld that is full penetration, testing is to be performed in accordance with the requirements for ‘T’, ‘K’ and ‘Y’ joints in 2.9.
      (b). For a branch weld that is either a partial penetration or fillet weld, testing is to be in accordance with the requirements for fillet welds in 2.8.
  • Destructive tests for weld cladding of steel
    • Where weld cladding or overlay is allowed by Chapter 13, and is considered as providing strength to the component to which it is welded, the type and location of test specimens are to be in accordance with Fig. 12.2.12, except that micro-sections are not required. Impact tests may be omitted where the base material does not have specified impact properties. The longitudinal tensile and bend tests are to be tested in a similar manner to transverse specimens specified in 2.7.2 and 2.7.6, respectively.

      Fig. 12.2.12 Type and location of test specimens for weld cladding
    • 2.11.2. Where the weld cladding is not considered as contributing to the strength of the component, but is required for corrosion or wear resistance, the type and location of test specimens are to be in accordance with Fig. 12.2.12, except that tensile and impact tests are not required.
    • 2.11.3. Where the weld cladding is applied for corrosion resistance, in addition to the above, weld metal analysis is to be performed on one of the micro-sections, on the final weld surface but 2 mm deep. The analysis is to be within the limits specified for the corrosion resistance required.
  • Mechanical test acceptance criteria for steels
    • Longitudinal all weld metal tensile test:
      (a). In general, the longitudinal all weld tensile test is to meet the minimum properties specified in Tables 11.3.2 or 11.4.2, as appropriate to the grade of steel and welding process used in the test.
      (b). Where the application is such that no consumable approvals are specified in Chapter 11, the longitudinal all weld tensile test tensile is to meet the minimum properties specified for the base materials used in the test.
      (c). For pressure vessels manufactured from carbon or carbon/manganese steels, the tensile strength from the longitudinal all weld tensile test is not to be less than the minimum specified for the plate material and is not to be more than 145 N/mm2 above this value,see Ch 13,4.8.3.
    • Transverse tensile test: The tensile strength measured from the transverse tensile test is not to be less than the minimum specified for the base material used in the test.
    • Bend tests:
      (a). In general, bend tests are to exhibit no defects exceeding 3,0 mm measured in any direction across the tension face of the specimen after being bent over the required diameter of former to the appropriate angle.
      (b). Bend tests for pressure vessel applications are to exhibit no defects exceeding 3,0 mm measured along the specimen or 1,5 mm measured transverse to the specimen axis, after bending.
      (c). In all cases, premature failure of the bend tests at the edges of the specimen is to not be cause for rejection unless these are associated with a weld defect.
    • Impact toughness tests:
      (a). Impact test specimens for hull construction are to be tested at the temperature, and are to achieve the minimum impact energy, as specified in Table 12.2.2.
      (b). Impact test specimens for applications other than hull construction are to be tested at the same temperature and achieve the same minimum energy values, as specified for the base materials used in the test.
      (c). Impact test acceptance criteria are to be in accordance with the above unless the Rules applicable to the particular construction specify more stringent requirements.
      (d). For quench and tempered steels, the required test temperature and absorbed energy are to be in accordance with that specified for the parent materials.

      Table 12.2.2 Impact test requirements for butt joints (t ≤ 50 mm) see Notes 1 and 2
      Grade of steel Test temperature (°C)
      see Note 4
      Value of minimum energy absorbed (J), see Note 4
      Manual or semi-automatic welded joints Automatically welded
      joints
      Downhand, Horizontal
      , Overhead
      Vertical upward, Vertical
      downward
      A, see Note 3 20 47 34 34
      B, see Note 3, D 0
      E -20
      A32, A36 20
      D32, D36 0
      E32, E36 -20
      F32, F36 -40
      A40 20 39 39
      D40 0
      E40 ?20
      F40 -40
      > 40 As specified for parent
      material
      As specified in Ch 11,4.3
      NOTES

      1. For thickness above 50 mm, impact test requirements are to be specially agreed.As specified for parent
      materialAs specified in Ch 11,4.3
    • Macro-examination: The macro-section is to reveal an even weld profile blending smoothly with the base material. The weld dimensions are to be in accordance with the requirements of the pWPS and any defects present are to be assessed against the non-destructive examination acceptance criteria given in 2.5.5.
    • Hardness surveys: The maximum hardness value reported is not to exceed 350 Hv for steels with a specified minimum yield strength up to ≤420 N/mm2, nor exceed 420 Hv for steels with a specified minimum yield strength in the range 420 N/mm2 to 690 N/mm2.
    • Weld fracture or break tests (for pressure vessel test welds): The faces of the broken fillet weld fracture or weld break test are to be examined for defects and assessed in accordance with the non-destructive acceptance criteria given in ISO 5817 Level B, except for excess convexity and excess throat thickness where Level C will apply.
  • Failure to meet requirements (Retests)
    • Where a tensile, bend or hardness specimen fails to meet requirements, further test specimens may be removed and tested in accordance with the requirements of Ch 2,1.4.1.
    • Where an impact specimen fails to meet requirements, a further set of three specimens may be removed and tested in accordance with the requirements of Ch 2,1.4.4.
    • Where a macro specimen reveals a defect that is planar in nature, the welding procedure test is to be considered as not satisfying the requirements and a new test assembly is required.
    • Where a macro specimen does not meet requirements as a result of a volumetric imperfection exceeding the permitted size, two additional specimens may be removed from the same test weld and examined. If either of these macro-sections also fails to satisfy the requirements, the welding procedure is to be considered as not having met the requirements.
    • If there is a single hardness value above the maximum values specified, additional hardness tests are to be carried out, either on the reverse of the specimen, or after sufficient grinding of the tested surface. None of the additional hardness values is to exceed the maximum hardness values specified, otherwise the welding procedure is to be considered as not having met the requirements.
    • Where there is insufficient material available in the welded test assembly to provide re-test specimens, subject to prior agreement with the Surveyor, a second assembly may be welded using the same conditions as the original test weld.
  • Test records
    • The procedure qualification record (PQR) is to be prepared by the manufacturer and is to include details of the welding conditions used in the test specified in 2.2 and the results of all the non-destructive examinations and destructive tests, including re-tests.
    • Provided that the PQR lists all the relevant variables and there are no inconsistent features and the results satisfy the requirements, the PQR may be endorsed by the Surveyor as satisfying the requirement of the Rules, see also 1.1.4.
  • Range of approval
    • A welding procedure qualification test that has successfully met the requirements may be used for a wider range of applications than those used during the test.
    • Changes outside of the ranges specified are to require a new welding procedure test.
    • Other ranges of approval from those specified in this Section may be agreed with the Surveyor, provided that they are in accordance with recognised National or International Standards.
    • Manufacturer. A welding procedure qualified by a manufacturer is valid for welding in workshops under the same technical and quality management.
    • Welding process and technique. The welding process and welding techniques approved are to be those employed during the welding procedure qualification test. Where multiple welding processes are used, these are to be employed in the same order as that used in the welding procedure qualification test. However, it may be acceptable to delete or add a welding process where it has been used solely to make the first weld run in the root of the joint, provided back gouging or grinding of the root weld is specified on the WPS. For multi-process procedures, the welding procedure approval may be carried out with separate welding procedure tests for each welding process.
    • Welding positions. Approval for a test made in any position is restricted to that position. To qualify a range of positions, test assemblies are to be welded for the highest heat input position, and the lowest heat input position, and all applicable tests are to be made on those assemblies. The above excludes welding in the vertical position with travel in the downward direction which will always require separate qualification testing and only be acceptable for that position.
    • Joint types. A qualification test performed on a butt weld may be considered acceptable for fillet and partial penetration welds, provided the same welding conditions are used. The range of approval depending on the type of joint for butt welds is given in Table 12.2.3.

      Table 12.2.3 Range of approval for different types of butt joints
      Type of welded joint for test assemblyl Range of approval
      Butt welding One side With backing A A,C,D
      Without backing A A,B,C,D
      Both sides With gouging C C
      Without gouging D C,D
    • Range of material types:
      • A qualification test performed on one strength level of steel may be used to weld all similar materials with the same or lower specified minimum yield stress with the exception of the two-run (T) or high welding heat input (A) techniques where acceptance is limited to the strength level used in the test. Similarly, a qualification test performed on a steel with one toughness level may be considered acceptable for welding all similar materials with the same or three toughness grades lower specified minimum toughness level.
      • For high strength quenched and tempered steels, for each strength level, welding procedures are considered applicable to the same and lower toughness grades as that tested. For each toughness grade, welding procedures are considered applicable to the same and one lower strength level as that tested. The approval of quenched and tempered steels does not qualify thermo-mechanically rolled steels (TMCP steels) and vice versa.
      • For weldable C and C-Mn steel forgings, welding procedures are applicable to the same and lower strength level as that tested. The approval of quenched and tempered steel forgings does not qualify other delivery conditions and vice versa. (d). For weldable C and C-Mn steel castings, welding procedures are applicable to the same and lower strength level as that tested. The approval of quenched and tempered steel castings does not qualify other delivery conditions and vice versa. Dissimilar materials. Where a qualification test has been performed using dissimilar materials, acceptance is to be limited to the materials used in the test.
    • Thickness and diameter range:
      • For straight butt welds, the material thickness range to be approved is to be based on the thickness of the test piece and the type of weld as shown in Table 12.2.4.
      • For butt welds between plates of unequal thickness, the lesser thickness is the ruling dimension.
      • For fillet welds and ‘T’ butt welds, Table 12.2.4 is to be applicable to both the abutting and through member thicknesses. In addition to the requirements of Table 12.2.4, the range of approval of throat thickness ‘a’ for fillet welds is to be as follows:
        - single run: 0,75a to 1,5a
        - multi-run: as for butt welds with multi-run (i.e. a =t)
      • Notwithstanding any of the above, the approval of maximum thickness of base metal for any technique is to be restricted to the thickness of the test assembly if three of the hardness values in the heat affected zone are found to be within 25 Hv of the maximum permitted.
      • The material diameter range to be approved is to be based on the diameter of the test piece and type of weld as shown in Table 12.2.5.

        Table 12.2.4 Welding procedure thickness approval range - Butt welds
        Test thickness,
        see Note 1
        (t in mm)
        Range approved
        All multi-run butt welds and all fillet welds
        see Notes 3 and 4
        All single-run or two-run two-run (T technique) butt welds
        t≤3 t to 2t 0,7t to 1,1t
        3 < t ≤ 12 3 to 2t 0,7 t to 1,1t
        12 < t ≤ 100 0,5t to 2t
        see Note 2
        0,7t to 1,1t
        see Note 5
        t > 100 0,5t to 1,5t 0,7t to 1,1t
        see Note 5
        NOTES

        1. Where the test plates have dissimilar thickness, the thickness, t, is to be based on the minimum thickness for butt welds and the maximum thickness for fillet welds.

        2. Subject to a maximum limit of 150 mm.

        3. For multi process procedures, the recorded thickness contribution of each process is to be used as a basis for the range of approval of the individual welding process.

        4. For vertical down welding, the test piece thickness, t, is the upper limit of the range of application.

        5. For processes with heat input over 5,0 kJ/mm, the upper limit of the range of approval is to be 1,0 t.0,5t to 1,5t0,7t to 1,1t
        see Note 5

        Table 12.2.5 Diameter range approved
        Diameter used for test,
        see Note 1
        Range of diameters
        approved
        D ≤ 25 mm 0,5D, see Note 2D
        D > 25 mm 0,5D, see Note 2
        NOTES

        1. D is the outside diameter of the pipe or the smallest side dimension of rectangular hollow section.

        2. Lower diameter range limited to 25Ø mm minimum.
    • Welding consumables:
      • For manual and semi-automatic welding used for the fill and capping weld runs, it may be acceptable to change the brand or trade name of the welding electrode or wire from that used in the test, provided the proposed alternative has the same or higher approval grading and the same flux type (e.g. basic low hydrogen, rutile, etc.) as used in that test.
      • For the consumable used to make the root weld of full penetration butt welds made from one side only, no change in the type or trade name of the consumable or backing material is permitted. Alternative backing materials may be used provided they are equivalent to those used for approval. Where the approved backing material is a low hydrogen grade and the steel being welded requires a low hydrogen backing material, testing of the alternative backing material is to confirm compliance with the requirements of Ch 11,7.
      • For processes with heat input over 5 kJ/mm, no change in the type or trade name of the consumable is permitted.
    • Shielding gas. For gas shielded welding processes, a change in shielding gas composition from that used in the test will require a new qualification test.
    • Heat Input. The upper limit of heat input approved is 25 per cent greater than that used in the test, or 5,5 kJ/mm, whichever is the smaller. With heat input over 5,0 KJ/mm, the upper limit is 10 per cent above that used in the test. In all cases, the lower limit of heat input approved is 25 per cent lower than that used in the test.
    • Current type. The current type used during the qualification test is to be the only type approved. Additionally, changes from or to pulsed current require new qualification tests.
    • Preheat temperature. The temperature used during the test is to be the minimum approved. Higher temperatures may be specified for production welds up to the maximum interpass temperature. Where hardness tests have been performed that exhibit results near the maximum permitted, an increase in preheat temperature is required when welding material of greater thickness than that used in the test.
    • Interpass temperature. The maximum interpass temperature recorded during qualification testing is to be the maximum approved. Lower temperatures may be specified for production welding, but no lower than the minimum preheat temperature.
    • Post-weld heat treatment. A qualification test performed with no post weld heat treatment is only acceptable for production welding where no heat treatment is applied. Where the qualification test has included a post weld heat treatment, this is to be applied to all welds made with the welding procedure. The average specified soak temperature may vary by up to 25°C from that tested.
    • Shop primers. Welding procedure qualification with shop primers qualifies welds without primer, but not vice versa.
    • Welding procedure specification (WPS)
      • A welding procedure specification (WPS) is to be prepared by the manufacturer detailing the welding conditions and techniques to be employed for production welding. The WPS is to be based on the conditions and variables used during the qualification test, and is to include all the ranges of the essential variables specified in 2.2.1 and 2.15.
      • The WPS should reference the procedure qualification record upon which it is based and is to be approved by the Surveyor prior to commencing production welding.

Section 3 Specific requirements for stainless steels

  • Scope
    • The requirements of this Section relate to the group of steel materials classed as stainless steels and include austenitic and duplex grades and martensitic grades.
    • In all cases, welding procedure tests are to be performed generally in accordance with Section 2 with the specific requirements specified below.
  • Austenitic stainless steels
    • The requirements of this Section relate to the group of stainless steel materials that are austenitic at ambient and sub-zero temperatures, (e.g. 304L, 316L types), see Table 3.7.1 in Chapter 3.
    • Impact tests are to be performed from specimens removed from the weld metal. Tests in the heat affected zone are not required.
    • Hardness tests are generally not required.
    • For cryogenic or corrosion resistant applications, the ferrite content in the weld cap region is to be measured and is to be in the range 2 to 10 per cent, with the exception of grades S 31245 and N 08904 where the content is to be nominally zero.
    • A qualification test performed on an austenitic grade may be considered acceptable for welding other austenitic steels with the same or lower level of alloying elements and the same or lower tensile strength.
    • A qualification test performed for cryogenic applications may be considered acceptable for chemical applications, but not vice versa.
  • Duplex stainless steels
    • The requirements of this Section relate to the group of stainless steel materials that have a ferritic-austenitic structure and are usually referred to as duplex or super duplex stainless steels (e.g. S 31803, S 32760).
    • Impact test specimens are to be removed from the weld and heat affected zone in accordance with Section 2 with the exception that impact test specimens notched at the FL + 10 mm location are not required. The specimens are to be tested at a temperature of 20°C or the minimum design temperature whichever is the lower and exhibit a minimum average energy of 40 J.
    • The corrosion resistance is to be maintained in the welded condition and the following tests are to be performed to demonstrate acceptable resistance, unless agreed otherwise.
      • A sample is to be removed from the weld and heat affected zone for micro-structural examination and is to be suitably prepared and etched so that the microstructures of the weld and heat affected zones can be examined at a magnification of x200 or higher. The micro-structure of the weld and heat affected zone is to be examined, the percentage grain boundary carbides and intermetallic precipitates is to be reported.
      • The ferrite content in the un-reheated weld cap and cap HAZ along with the weld root and root HAZ are to be measured and reported. The ferrite content is to be in accordance with Table 12.3.1. Where the intended construction is such that the corrosion medium is only in contact with one surface of the weld (i.e. the weld root), the ferrite determination need only be reported in that surface area.
      • Corrosion testing is to be performed on samples removed from the weld such that both the weld and HAZ are included in the test. The critical pitting temperature is to be determined in accordance with ASTM G48 Method C and meet the requirements specified in Table 12.3.1. The cap and root surfaces are to be inspected for evidence of pitting and may require probing the surface with a needle. Pitting found on the ends of the specimen in the weld cross-section may be ignored. The use of the weight loss method for corrosion testing may be accepted subject to special consideration.

        Table 12.3.1 Requirements for ferrite content and corrosion tests for duplex stainlesssteel test welds
        Duplex Stainless
        Steel
        Material Grade
        Weld and HAZ
        Ferrite content
        Minimum Critical
        Pitting Temperature(CPT)
        S 31260 30 to 70% 20°C
        S 31803 30 to 70% 20°C
        S 32550S 31260 35 to 65% 25°C
        S 32750 35 to 65% 25°C
        S 32760 35 to 65% 25°C
      • Where the test weld is between a grade of carbon steel and duplex stainless steel, the test requirements of 3.3.3(a) and (c) are not required and the ferrite content of the weld and the duplex heat affected zone are to be reported for information.
      • A qualification test performed on a duplex stainless steel grade may be considered acceptable for welding other duplex grades which have the same or less stringent mechanical or corrosion properties.
      • The range of heat input is not to vary by more than +10 per cent or 25 per cent from that used during testing.
      • Martensitic stainless steels
        • The requirements of this Section relate to the group of stainless steel materials that have a martensitic structure at ambient temperatures, see Table 4.5.1 in Chapter 4.
        • The results of the hardness survey results are to be reported for information purposes only.
        • A qualification test is considered acceptable only for the grade of material used in the test.

Section 4 Welding procedure tests for non-ferrous alloys

  • Requirements for aluminium alloys
    • The requirements for welding procedure qualification tests for aluminium alloys are to be in accordance with the general requirements of Section 2 with the following exceptions and specific requirements.
    • 4.1.2. Non-destructive examination is to be performed in accordance with 2.5 and the assessment of results is to be in accordance with Table 12.4.1 and Table 12.4.2.

      Table 12.4.1 Acceptance criteria for surface imperfections of aluminium alloys
      Surface discontinuity Classification according to
      ISO 6520-1
      Acceptance criteria
      Crack 100 Not permitted
      Lack of fusion 401 Not permitted
      Incomplete root penetration in butt joints welded from one side 4021 Not permitted
      Surface pore 2017 d ≤ 0,1s or 0,1a
      max. 1,0 mm
      Uniformly distributed porosity (see Note 1) 2012 ≤ 0,5% of aream
      Clustered porosity 2013 Not permitted
      Continuous undercut 5011 Not permitted
      Intermittent undercut 5012 h ≤ 0,1t or 0,5 mm (whichever is the lesser)
      Excess weld metal (see Note 2) 502 h ≤ 1,5 mm + 0,1b or 6 mm (whichever is the lesser)
      Excess penetration 504 h ≤ 4 mm
      Root concavity (see Note 2) 515 h ≤ 0,05t or 0,5 mm (whichever is the lesser)
      Linear misalignment (see Notes 3 and 4) 507 h ≤ 0,2t or 2,0 mm (whichever is the lesser)
      Symbols
      a = nominal throat thickness of a fillet weld
      b = width of weld reinforcement

      d = diameter of a gas pore

      h = height or width of an imperfection

      s = nominal butt weld thickness
      t = wall or plate thickness (nominal size)
      NOTES
      1. To be in accordance with EN ISO 10042.

      2. A smooth transition is required.

      3. The limits for linear misalignment relate to deviations from the correct position. Unless otherwise specified, the correct position is to be taken when the centrelines coincide.

      4. Dimensional tolerances not specified in these Rules are to be mutually agreed between the manufacturer and the Surveyor.

      Table 12.4.2 Acceptance criteria for internal imperfections of aluminium alloys
      Internal discontinuity Classification according to
      ISO 6520-1
      Acceptance criteria
      Crack 100 Not permitted
      Lack of fusion 401 Not permitted
      Incomplete penetration 402 Not permitted
      Single gas pore 2011 d ≤ 0,2s or 0,2a or 4 mm (whichever is the lesser)
      Linear porosity (see Note 2) 2014 Not permitted
      Uniformly distributed porosity (see Note 2) 2012 0,5t to 3t ≤ 1% of area
        > 3t to 12t ≤ 2% of area
        >12t to 30t ≤ 3% of area
        > 30t ≤ 4% of area
      Clustered porosity (see Note 1) 2013 dA ≤ 15 mm or wp (whichever is the lesser)
      Elongated cavity
      Wormhole
      2015
      2016
      l ≤ 0,2s or 0,2a or 3 mm (whichever is the lesser)
      Oxide inclusion (see Note 2) 303 l ≤ 0,2s or 0,2a or 3 mm (whichever is the lesser)
      Tungsten inclusion 3041 h ≤ 0,2t or 2,0 mm (whichever is the lesser)
      Copper inclusion - The sum of the acceptable individual imperfections in any cross-section is not to exceed 0,2t or 0,2a(whichever is the lesser)

      Symbols
      a = nominal throat thickness of a fillet weld
      d = diameter of a gas pore
      h = height or width of an imperfection
      s = nominal butt weld thickness
      t = wall or plate thickness (nominal size), in mm
      wp = width of weld or width or height of cross-sectional area
      dA = diameter of area surrounding gas pores l = length of imperfection in longitudinal direction of weld
      NOTES
      1. For this acceptance criterion, linear porosity is to be considered as three aligned gas pores in a length of 25 mm.

      2. Porosity is to be determined in accordance with ISO 10042. The requirements for a single gas pore are to be met by all the gas pores within this circle. Systematic clustered porosity is not permitted.
    • Acceptance of the mechanical tests is to be in accordance with Ch 11,9. Welding of the strain hardened and heat treatable aluminium alloys will generally result in a loss of tensile strength in the heat affected zone below that specified for the base materials and the tensile strength acceptance criteria to be applied is that specified for the material in the annealed or ’as fabricated’ condition. Minimum values of tensile strength measured on the transverse tensile samples are given in Table 12.4.3.

      Table 12.4.3 Tensile strength requirements by grade for aluminium alloys
      Parent material Grade
      (alloy designation)
      Minimum tensile strength
      (N/mm2)
      5754 190
      5086 190
      5083 275
      5383 290
      5059 330
      5456 290
      6005A 170
      6061 170
      6082 170
    • Impact tests and hardness surveys are not required for aluminium alloys.
    • Four side bend tests may be used in place of root and face bends where the test thickness exceeds 12 mm, and longitudinal bend tests may be used instead of transverse tests where the test weld is between different grades of alloy. Bend specimens are to be bent round a former in accordance with Table 11.9.1, with the exception that the 6000 series alloys may be bent round a former with D/t = 7.
    • The ranges of approval to be applied to the WPS are to be as specified for steel in 2.15 with the following exceptions:
      • The welding positions approved are as detailed in Table 12.4.4.
      • The aluminium alloys are grouped into three groups as follows:
        - Group A: aluminium-magnesium alloys, with Mg content ≤3,5 per cent (alloy 5754).
        - Group B: aluminium-magnesium alloys with 4 per cent ≤Mg ≤5,6 per cent (alloys 5059, 5083, 5086, 5383 and 5456).
        - Group C: aluminium-magnesium-silicon alloys (alloys 6005A, 6061 and 6082).
        For each group, the qualification made on one alloy qualifies the procedure also for the other alloys in the group, with equal or lower tensile strength after welding. The qualification made on group B alloys qualifies the procedure for Group A alloys also. Approval for the range of material grades is summarised in Table 12.4.5.
    • The qualification of a procedure carried out on a test assembly of thickness t is valid for the thickness range given in Table 12.4.6. In the case of butt joints between dissimilar thicknesses, t is the thickness of the thinner material. In the case of fillet joints between dissimilar thicknesses, t is the thickness of the thicker material. In addition to the requirements of Table 12.4.6, the range of the qualification of throat thickness of fillet welds, a, is given in Table 12.4.7. Where a fillet weld is qualified by a butt weld test, the throat thickness range qualified is to be based on the thickness of the deposited weld metal.
    • The range of shielding gas compositions approved is to be in accordance with Table 11.9.2 in Chapter 11.
    • A change in the brand or trade name of the filler metal from that used in the test is acceptable, provided that the proposed consumable has the same or higher strength grading.
    • A change in post-weld heat treatment or ageing is not permitted, except that for the heat treatable alloys, artificial ageing may give approval for prolonged natural ageing.

      Table 12.4.4 Welding procedure approval, welding positions for aluminium alloys
      Test Position Positions Approved
      Downhand D D
      Horizontal-vertical X D, X
      Vertical up Vu D, X, Vu
      Overhead O D, X, Vu and O
      NOTE

      Welding in vertical down (Vd) position is not recommended

      Table 12.4.5 Welding procedure approval, aluminium material grades approved
      Material used in qualification test Material Grades approved
      5754 5754      
      5086 5086 5754    
      5083 5083 5086 5754  
      5383 5059 5083 5086 5754
      5059 5059 5083 5086 5754
      5456 5456 5383 5086 5754
      6005A 6005A 6082 6061  
      6082 6005A 6082 6061  
      6061 6005A 6082 6061  
      NOTE

      Approval includes all the different strained and tempered conditions in each case.

      Table 12.4.6 Range of qualification for parent material thickness
      Thickness of test assembly,t (mm) Range of qualification
      Multi pass welds
      Range of qualification
      All single-run or two-run (T technique) butt welds
      t ≤ 3 0,5 to 2t 0,5t to 1,1t
      3 < t ≤ 20 3 to 2t 0,5t to 1,1t
      t >20 ≥ 0,8t 0,5t to 1,1t

      Table 12.4.7 Range of qualification of throat thickness for fillet welds
      Throat thickness of test piece, a (mm) Range of qualification
      a < 10 0,75 a to 1,5 a
      a ≥ 10 ≥ 7,5
  • Requirements for copper alloys
    • The requirements for welding procedure qualification tests for copper alloys are to be in accordance with the requirements for steel as given in Section 2 with the following exceptions and additions.
    • Impact tests on copper alloys are not required.
    • Hardness tests are not required for seawater service.
    • For the welding of cast copper alloys for propellers, the minimum tensile strength from the transverse tensile test is to be in accordance with Table 12.4.8.

      Table 12.4.8 Minimum transverse tensile strengths for welded copper alloy propellers
      Alloy designation Minimum tensile strength (N/mm2)
      CU 1 370
      CU 2 410
      CU 3 500
      CU 4 550
    • Bend tests are to be performed over a diameter of former as detailed in Table 12.4.9.

      Table 12.4.9 Former diameters for bend testing of copper alloy welds
      Alloy designation
      (see Chapter 9)
      Former diameter (D/t)
      Cast propellers:  
      CU1 4
      CU2 4
      CU3 6, see Note 1
      CU4 6, see Note 1
      Other short freezing range castings:
      Copper-Nickel 90/10 4
      Copper-Nickel 70/30 4
      Aluminium bronze 6
      Wrought alloys (tubes and pipes):
      Copper-phosphorus 3
      Aluminium-brass 3
      90/10 Copper-nickel-iron 3
      70/30 Copper-nickel-iron 3
      NOTE

      Where the qualification tests for these alloys are subjected to post-weld heat treatment the former diameter may be increased to D/t = 10.
    • The range of approval to be applied to the WPS is to be as specified in 2.15 with the exception of the material grades which are detailed in Table 12.4.10. Table 12.4.10 Range of approval for copper alloy material grades

      Table 12.4.10 Range of approval for copper alloy material grades
      Category Alloy grade used in the qualification test Alloy grades approved
      Propellers CU1 CU1
      CU2 CU1 and CU2
      CU3 CU1, CU2 and CU3
      CU4 CU4 see Note 1
      Tubes/pipes 90/10 Copper - Nickel-Iron 90/10 Copper - Nickel-Iron
      70/30 Copper - Nickel - Iron 70/30 Copper - Nickel - Iron and
      90/10 Copper - Nickel - Iron
      Tupes/pipes
      see Note 2
      Copper-Phosphorus deoxidised - arsenical Copper-Phosphorus deoxidised - arsenical
      Copper-Phosphorus deoxidised - arsenical Copper-Phosphorus deoxidised - non arsenical
      Aluminium-brass Aluminium-brass
      NOTES

      1. Where a CU3 type welding consumable has been used for the qualification test, the range of approval may also include welding of CU3.

      2. These grades have limited weldability and approval to weld is subject to the materials satisfying the requirements of Table 9.3.1 in Chapter 9.

Section 5 Welder qualification tests

  • Scope
    • The requirements of this Section relate to qualification of welders involved in welded construction associated with ships, or other marine structures, and products or components intended for use on or in these structures.
    • The requirements relate to fusion welding processes that are designated as manual, semi-automatic or partly mechanised. Special consideration will be given to other welding processes adapted from these requirements.
    • Prior to commencing production welding, the welder is to have performed a qualification test that satisfies these requirements. It is the responsibility of the manufacturer to ensure that the welder possesses the required level of skill for the work to be undertaken.
    • The qualification of welders is to be documented by the manufacturer and the records are to be available for review by the Surveyor.
    • Welder qualification tests made in accordance with EN, ISO, JIS, ASME or AWS may be considered for acceptance provided that, as a minimum, they are equivalent to, and meet the technical intent of these Rules to the satisfaction of the Surveyor.
  • Welder qualification test assemblies
    • The welding of the welder qualification test assembly is to simulate, as far as practicable, the conditions to be experienced in production and be witnessed by the Surveyor. The test is to be carried out on a test assembly piece and not by way of production welding.
    • The test is to simulate, as far as practicable, the welding techniques and practices to be encountered during production welding. The test assembly is to be designed to test the skill of the welder and have the shape and dimensions appropriate to the range of approval required.
    • The inspection length of the test weld is to be such as to permit the removal of all the necessary test specimens and for plate tests, but in no case is to be less than 250 mm. The test assembly is to be set in one of the positions as shown in Fig. 12.2.2.a appropriate to the welding positions to be approved.
    • A welding procedure specification (WPS) is required for the execution of the qualification test and is to include the information specified in 2.2.1, as a minimum.
    • The test assembly is to be marked with a unique identification and the inspection length is to be identified prior commencing welding. For pipe welds, the whole circumference is to be considered as the inspection length.
    • During welding of the test assembly, the welding time is to be similar to that expected under production conditions. For manual or semi-automatic processes, at least one stop and re-start in the root and in the top surface layer is to be included in the inspection length and marked for future inspection.
    • During welding of the test assembly, minor imperfections may be removed by the welder by any method that is used in production, except on the surface layer.
    • he Surveyor may stop the test if the welding conditions are not correct or if there is any doubt about the competence of the welder to achieve the required standard.
  • Examination and testing
    • Each completed test weld is to be examined and tested in accordance with the requirements of Table 12.5.1.

      Table 12.5.1 Welder qualification test requirements
      Category Butt welds Fillet welds Pipe branch welds
      Visual 100% 100% 100%
      Surface crack detection See Note 1 100% 100%
      Radiography 100%
      See Notes 2 and 6
      Not required Not required
      Radiography 4 required
      See Notes 3 and 6
      Not required Not required
      Fracture tests Not required 1 required
      See Note 4
      Not required
      Macro Not required 1 required
      See Note 4
      4 required
      See Note 5
      NOTES

      1. Surface crack detection examination may be required by the Surveyor in order to clarify the acceptability of any weld feature.

      2. Radiography may be replaced by ultrasonic examination for carbon and low alloy steels where the thickness exceeds 8 mm.

      3. Bend tests are required for gas metal arc welding with solid wire (GMAW) and oxy-acetylene welding.

      4. The fracture test may be replaced with 4 macro sections equally spaced along the inspection length.

      5. Macro-sections are to be separated by 90° measured around the abutting pipe member.

      6. Radiography and bend tests are required for tests in aluminium alloys.
    • Visual examination is to be performed in the as welded state prior to any other assessment.
    • For plate butt welds, fracture testing may be used in place of radiography.
    • Where a backing strip has been used, it is to be retained for non-destructive examinations, but is to be removed prior to performing any bend or fracture tests.
    • Where fracture tests are required, they are to sample as much of the inspection length as practicable and the test assembly may be cut into several test specimens to achieve this. Testing is to be performed as shown in Figs. 12.5.1(a) or 12.5.1(b).

      Fig. 12.5.1.a Preparation and fracture testing of test specimens for a fillet weld in plate

      Fig. 12.5.1.b Preparation and fracture testing of test specimens for a butt weld in plate
    • For butt weld tests in aluminium alloys both radiography and bend tests are required.
    • When bend tests are required, 2 root and 2 face bends are to be tested and where the test thickness exceeds 12 mm, these may be substituted by 4 side bends specimens. The diameter of former to be used is to be in accordance with that specified for welding procedure qualification testing given in 2.7.6(a).
    • Where macro examination is required, the specimen is to be polished and etched to reveal the weld runs and heat affected zones, and be examined at a magnification between x5 and x10.
  • Acceptance criteria
    • The acceptance criteria are to be in accordance with 2.5.5.
    • Fracture tests and macro-sections are to be assessed in accordance with the non-destructive examination acceptance criteria.
    • Bend tests are considered acceptable if after bending through an angle of at least 180°, there are no defects on the tension side of the specimen greater than 3 mm in any direction.
  • Failure to meet requirements
    • Where a macro-section fails to meet requirements, one additional specimen may be removed from the test assembly and examined.
    • Where a bend or fracture test specimen fails to meet requirements, two additional specimens may be prepared from the same test assembly. If there is insufficient material, the welder may be permitted to weld an additional assembly to the same WPS, at the discretion of the Surveyor.
    • Where any of the additional test specimens fails to satisfy the requirements, the test will be considered as not meeting the requirements.
    • Where a test fails to comply with the acceptance criteria, the welder may be permitted to weld a second test piece. If this does not meet requirements, the welder is to be considered as not being capable of achieving the requirements.
  • Range of approval
    • Upon successful completion of all the necessary examinations and tests, the welder is to be considered qualified. The essential variables and the range of welding conditions for which the welder is considered approved are specified in the following paragraphs.
    • Welding variables such as preheat, interpass temperature, heat input and current type are not considered welder qualification variables. However, if the WPS used for testing specify these, they are to be included in the test and the welder is expected to follow the specific instructions.
    • Where the WPS used for the welder qualification test specifies post-weld heat treatment, this need not be applied to the test weld unless bend tests are required and the material exhibits low ductility in the as welded condition.
    • The qualification test performed by a manufacturer is only applicable to workshops under the same technical control and quality system as that used for the test.
    • The welding process used in the qualification test is the process approved. However, it is possible for the welder to use more than one process in the test and the range of approval that may be applied to each will be within the limits of the essential variables appropriate to the part of the test where each welding process was used.
    • Material types are to be grouped as shown in Table 12.5.2 for welder qualifications. A qualification test performed on one material from a group will permit welding of all other materials within the same group. In addition, qualification on one group of materials may confer approval to weld other groups as shown in Table 12.5.3.

      Table 12.5.2 Welder qualification materials groupings
      Material group Material description Typical LR Grades Rules for Material references
      WQ 01 Low carbon unalloyed, A, B, D and E Ch 3,2
      C/Mn, or AH to FH32 and 36 Ch 3,3
      Low alloyed steels (Re ≤ 360 N/mm2) Boiler 510FG and lower Ch 3,4
      LT-AH to FH32 and 36 Ch 3,6
      U1 and U2 Ch 3,9 and Ch 10
      Steel castings Ch 4,2, 3, 6 and 7
      Steel pipes Ch 6,2, 3, 4 and 6
      WQ 02 Cr-Mo, or 13CrMo45 and 11CrMo910 Ch 3,4
      Cr-Mo-V creep resisting steels 1Cr½Mo and 2¼Cr1Mo Ch 4,6 and Ch 6,2, 3
      and 6
      ½Cr½Mo¼V Ch 4,6 and Ch 6,2
      WQ 03 High strength fine grained, AH to FH40 to 69 Ch 3,3 and 10
      Normalised or quenched, or LT-AH to LT-FH40 Ch 3,6
      Tempered structural steels (2,0 ? 5% 1½ , 3½ Ni steels and castings Ch 3,6, Ch 4,7 and Ch 6,4
      Ni, with Re > 360 N/mm2) U3, R3, R3S and R4 Ch 3,9 and Ch 10
      WQ 04 Ferritic, or martensitic stainless steels (12 to 20% Cr) 13% Cr (martensitic) Ch 4,5 (martensitic)
      WQ 05 Ferritic low temperature steels 5Ni and 9Ni Ch 3,6
      WQ 011 Ferritic-austenitic stainless steels, 304, 316, 317, 321 and 347 Ch 3,7 and 8
      WQ 03 Austenitic stainless steels, or Cr-Ni steels S31260, S31803, S32550 and S32750 Ch 4,8 and Ch 6,5
      WQ 22a Aluminium alloy-Non-heat treatable Mg < 3,5% 5754 Chapter 8
      WQ 22b Aluminium alloy-Non-heat treatable 3,5% < Mg < 5,6% 5083 and 5086 Chapter 8
      WQ 23 Copper alloys for propellers - Manganese bronze Cu1 Ch 9,1
      WQ 31 Copper alloys for propellers - Nickel - aluminium bronze Cu2 Ch 9,1
      WQ 32 Copper alloys for propellers - Nickel - aluminium bronze Cu3 Ch 9,1
      WQ 33 Copper alloys for propellers - Manganese - aluminium bronze Cu4 Ch 9,1
      WQ 34 Copper alloys for tubes-Copper phosphorus Deoxidised ? non-arsenical and arsenical Ch 9,3
      WQ 35 Copper alloys for tubes - Aluminium brass Aluminium brass Ch 9,3
      WQ 36 Copper alloys for tubes - Copper - nickel - iron 70/30 Cu/Ni and 90/10 Cu/Ni Ch 9,3


      Table 12.5.3 Welder qualification, range of approval for material groups
      Material Group used for testing Welder qualification, range of approval for material groups
      WQ 01 WQ 01      
      WQ 02 WQ 01 WQ 02    
      WQ 03 WQ 01 WQ 02 WQ 03  
      WQ 04 WQ 01 WQ 02 WQ 04  
      WQ 05 WQ 05    
      WQ 11 WQ 11 WQ 05, see Note 1 WQ 04, see Note 1  
      WQ 22a WQ 22a WQ 22b    
      WQ 22b WQ 22a WQ 22b    
      WQ 23 WQ 22a WQ 22b WQ 23  
      WQ 30 WQ 30 WQ 31 WQ 32 WQ 33
      WQ 31 WQ 30 WQ 31 WQ 32 WQ 33
      WQ 32 WQ 30 WQ 31 WQ 32 WQ 33
      WQ 33 WQ 30 WQ 31 WQ 32 WQ 33
      WQ 34 WQ 34 WQ 35    
      WQ 35 WQ 34 WQ 35    
      WQ 36 WQ 36    
      NOTE

      Provided an austenitic welding consumable compatible with material group WQ 11 is usedWQ 36
    • A qualification test performed on one thickness will confer approval to weld other thicknesses as specified in Table 12.5.4. Where welding is required between materials of different thickness, the reference thickness for approval purposes is to be the lesser thickness.

      Table 12.5.4 Welder qualification, range of approval for material thickness
      Material type Test piece thickness
      (mm)
      Range approved, see Note
      (mm)
      Steel and copper alloys t ≤ 3 t to 2t
      3 < t ≤ 12 3,0 to 2t
      t > 12 ≥ 5,0
      Aluminium alloys t ≤ 6 0,7 to 2,5t
      6 < t ≤ 15 6,0 < t ≤ 40,0
      t > 40 mm 41 to 2t
      NOTE

      For oxy-acetylene welding the maximum thickness is limited to 1,5 t. WQ 22aWQ 22b
    • A qualification test performed on plate confers approval to weld on pipes having an outside diameter greater than 500 mm in a fixed position (see Table 12.5.5 and Table 12.5.6).

      Table 12.5.5 Welder qualification, diameter range of approval for pipes and hollow sections
      Material type Test piece thickness
      (mm)
      Range approved, see Note
      (mm)
      Steel and copper alloys D ≤ 25 D to 2D
      25 < D ≤ 150 0,5D to 2D, see Note 1
      D > 150 ≥ 0,5D
      Aluminium alloys D ≤ 125 0,25D to 2D
      D > 125 ≥ 0,5D
      Plate, see Note 2 ≥ 500
      NOTES

      1. Subject to 25 mm minimum diameter.

      2. Plate qualification will approve welding on pipes greater than 150 mm diameter when the pipe is rotated
    • A qualification test performed using a specific diameter of pipe will give approval to weld other diameters as shown in Table 12.5.5. For branch welds, the diameter upon which approval is based is to be the branch member.
    • A qualification test performed on a butt weld may be considered as giving approval for fillet welds.
    • A butt qualification test welded from one side, with the root unsupported (i.e. no backing), will give approval for welds made from both sides with or without back gouging or grinding, but not vice versa.

      Table 12.5.6 Welding position ranges for welder qualification
      Test weld conditions Positions qualified
      Type of weld Test position Plate Pipe, see Note 1
      Butt weld Butt weld Butt weld Fillet weld
      Plate butt, see Note 5 D D D D D
      X D,X D,X D D,X
      Vu D, Vu D, X, Vu D D, Vu
      Vd Vd Vd - -
      O D, X, Vu, O D, X, Vu, O D D, X, Vu, O
      Plate Fillet, see Note 5 D - D - D
      X - D,X - D,X
      Vu - D, X, Vu - D, X, Vu
      Vd - Vd - -
      O - D, X, Vu, O - D, X, Vu, O
      Pipe butt D D D,X D D,X
      X D,X D,X D,X D,X
      D+Vu+O, see Note 3 D, Vu, O D, X, Vu, O D, Vu, O D, Vu, O
      D+Vd+O, see Notes 2 and 3 Vd Vd Vd Vd
      Axis at 45°, see Note 4, Travel Vu D, X, Vu, O D, X, Vu, O D, X, Vu, O D, X, Vu, O
      Axis at 45°,see Notes 2, 3 and 4, Travel Vd Vd Vd Vd Vd
      Pipe fillet D - D - D
      X - D,X - D,X
      D+Vu+O see Note 3 - D, X, Vu, O - D, X, Vu, O
      Axis at 45°, see Notes 2, 3 and 4, Travel Vd - Vd - Vd
      NOTES

      1. Pipe D position means pipe in horizontal position and rotated, see Fig. 12.2.2(b) and Fig. 12.2.2(d).

      2. Vd position not usually recommended for pipe welds less than 500 mm diameter.

      3. Pipe fixed with axis in the horizontal position (e.g. ASME 5G).

      4. Pipe fixed with axis at 45° to the horizontal (e.g. ASME 6G).

      5. Plate qualification tests confers approval to weld pipes with diameter greater than 500 mm.
    • A qualification test performed in one position will give approval to weld in other positions as shown in Table 12.5.6.
    • For manual metal arc welding with covered electrodes, a qualification test performed using an electrode with one type of coating will only be approved for welding with that type of coating. However, a qualification test performed using a basic low hydrogen type coating will confer approval to use electrodes with rutile coatings.
    • For gas shielded welding processes that use a single component shielding gas, no change to the gas composition is permitted from that tested. Where the test has used a two component shielding gas, a change in the ratio of component gases is permitted, provided that one of the components is not reduced to zero. Where the test has used a three component shielding gas, changes are permitted in the ratio of component gases and the gas with the smallest ratio may be reduced to zero, provided this does not change the shielding gas from an active one to an inert one or vice versa. In addition, where a change in shielding gas composition requires a different welding method or technique to be employed, a new qualification test will be required.
    • A change of welding flux from that used for the test is permitted.
    • Welders qualification certification
      • All the relevant conditions used during the test are to be entered on the welder’s qualification certificate along with the permitted range of approval.
      • If the Surveyor is satisfied that the welder has demonstrated the appropriate level of skill and all tests are satisfactory, the Surveyor will endorse the certificate verifying that the details contained on it are correct and that the test welds were prepared, welded and tested in accordance with the specified Rules, Codes or Standards.
      • The welder is considered to be approved for an initial validity period of 2 years. The welder is considered to have retained the qualification subject to the manufacturer confirming every 6 months that the welder has used the welding process with acceptable performance in the preceding 6 months.
      • After 2 years, the Surveyor may extend the validity of the approval for another period of two years provided that records or documented evidence is made available confirming acceptable welding performance, within the original range of approval, without a break exceeding 6 months. The Surveyor will signify acceptance of the extension to the validity by endorsing the certificate.
      • Where there is any reason to question the welder’s ability, or there is a lack of continuity in the use of the welding process, or insufficient recorded evidence of acceptable weld performance, the welder is to perform a new qualification test.
      • Where the manufacturer has existing welders that have previously performed qualification tests, these may be considered for acceptance provided they satisfy the above requirements and the tests have been performed in the presence of an independent examiner that is acceptable to the Society.
      • Not withstanding the above, the Surveyor may at any time request a review of a welder’s qualification records. If there is any reason for doubt concerning the skill of the welder, the Surveyor may withdraw the qualification and require a re-qualification test to be performed.