Api Specification 2b 51034

API Specification 2B • Specification for the Fabrication of Structural Steel Pipe . • Sixth Edition, July 2001:Effective from Jan.1 2002. • Scope: It covers the fabrication of structural steel pipe formed from steel plate with longitudinal and circumferential butt-welded seams suitable for use in offshore structures • Size 14” and large (40in. For LWDS) • Thickness 3/8in.(9.5mm) and greater • Max.length – 40ft(12.19m)

API Specification 2B • •

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Definitions Can – A section of structural steel pipe with no girth weld Girth weld – Circumferential butt welded seam lying in a plane perpendicular to the longitudinal axis of the pipe, used to tubular sections into lengths of straight pipe Longitudinal seam – Butt welded seam which is parallel to the axis of the pipe. Pile - Cylindrical tubular member fabricated from one or more lengths of structural pipe, usually driven through a leg or sleeve of an offshore platform , that carries vertical loads and resist lateral forces

API Specification 2B Material • As specified by the purchaser. Purchaser shall specify the grade and quality of plate steel • If the plate is supplied by the fabricator, mill test certificate must be available and also mill identification numbers.

API Specification 2B • • • • • •

Fabrication Normally Cold formed (below 4000F) Hot formed with approved procedures Purchaser shall specify the plate rolling direction if the plate is to be oriented in a specific direction. All welds shall be complete t penetration welds in accordance with AWSD1.1,2000,Structural welding code. SAW process shall be used for all welding unless otherwise approved by the purchaser – except tack welds, root es and repair welding. Welding electrodes and fluxes shall confirm to AWS spec. and match the minimum ultimate strength of the base material and provide a minimum of 20ft-lbs Charpy V Notch impact energy at 00F

API Specification 2B •

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Fabrication contd… Longitudinal welds – Radial offsets of abutting edges of LWS shall not exceed 1/8in(3.2mm). – For LWDS pipes, no two longitudinal weld seams shall be closer than one pipe diameter or 5ft whichever is greater. – Longitudinal seams of ading cans shall be staggered as below – Single seam – 900 to 1800 LWDS (1800) – 450 TO 900 Other LWDS – min. 25% of smaller seam spacing Girth welds – Radial offsets of abutting edges of girth seams shall not exceed 0.2T (Tsmall thickness) or 1/4in. Max, provided the offset exceeding 1/8” is welded from both sides – No two girth welds shall be located closer than one pipe diameter or 3ft, whichever is less. – There shall be no more than two girth welds in any 10ft-interval of pipe. – For LWDS pipe, no two girth welds shall be located closer than 10ft

API Specification 2B Dimensions and Tolerances • Diameter, Length and Wall thickness – Diameter, Length and Wall thickness shall be as specified by the purchaser. – The length of each pipe shall not vary more than +1 ½” per 10ft of length.

• Roundness – Out of roundness (difference betwn major and minor outside diameter at any point in length shall not exceed the following – 1% of OD or ¼” max. for wall thickness upto 2” – For wall thickness above 2“ out of roundness to wall thickness ratio shall not exceed 1:8 – For pipes exceeding 48” dia, max permitted is ½” , provided the circumference tolerance is maintained within +1/4”.

• Circumference – Outside circumference shall be within +1% of the nominal circumference or within+1/2” whichever is less.

API Specification 2B Dimensions and Tolerances contd.. • Straightness – Max. allowable straightness deviation in any 10ft length – 1/8” – For above 10ft length -( 1/8” x total length in ft)/10ft , not to exceed 3/8” in any 40ft length.

• Pipe ends – Unless specified, it shall be 30 degrees with +2.5 degrees with root face of 1/6”+1/32”. – The length of each pipe shall not vary more than +1 ½” per 10ft of length.

API Specification 2B •

Inspection and Repair Inspection – Fabrication and Inspection as per AWSD1.1

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Weld Inspection – All welds shall be inspected on the inside and outside surfaces. Weld profile shall meet the requirements of AWSD1.1, section 5.24

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Nondestructive Examination – RT or UT - 100% of each girth weld & 10% of spot testing of each longitudinal weld(including the extreme ends) as per AWSD1.1

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Repair of Base Metal Imperfections – Imperfections detected in the base petal in the finished tube no deeper than 5% of the specified nominal thickness or 1/16” in depth need not be removed. Imperfections above this shall be ground to sound metal. – Thickness in the ground area shall not be reduced more than 7% of the nominal thickness or more than 1/8”. – Imperfections above this and less than 20% of nominal wall thickness may be repaired by welding. – Repair of defects deeper than 20% thickness or width more than 20% of nominal diameter shall not be repaired.

API Specification 2B Marking • Inspection – Each section of the pipe shall be paint stenciled on the inside of both ends with letters of height 1” min with the following details. – Fabricator’s name – API Monogram shall be applied – API 2B – Plate material designation – Nominal Outside diameter – Nominal wall thickness – Specified supplementary requirements, SR1,SR2,SR3 or SR4

API Specification 2B Supplementary requirements •

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SR1 Plate Rolling Direction Orientation – SR1.1 Orientation of the pipe axis relative to the final rolling direction of the pate shall be longitudinal or Transverse as specified in the purchase order – Pipe fabricated as per this supplementary requirement shall be identified by marking S-1L or S-1T CVN Toughness Tests – Notch toughness tests shall be conducted as a requirement of the welding procedure qualification tests as per AWSD1.1 – Pipe shall be identified 100 percent Radiographic Examination – 100% RT of the longitudinal seam shall be conducted

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Matching weld CVN Toughness for Designated Plate Material – Charpy test shall be conducted for specimens from the weld metal and HAZ of a simulated Production weld coupons shall be tested