API Spec 2B:2001(R2012) pdf download.Specification for the Fabrication of Structural Steel Pipe
1 Scope
1.1 This specification covers the fabrication of structural steel pipe formed from plate steel with longitudinal and cir- cumferential butt-welded seams, typically in sizes 14 in. out- side diameter (OD) and larger (40 in. and larger for LWDS) with wall thickness 3 / 8 in. and greater (up to a nominal 40 ft in length) suitable for use in construction of welded offshore structures. The use of the ERW process or spiral welded pipe is not included in this specification. Pipe fabricated under this specification is intended to be used primarily in piling and main structural members, including tubular truss connections, where internal stiffeners are not usually required.
1.2 Manufacturers desiring to apply the API Monogram to the products covered by this specification shall demonstrate to the satisfaction of the American Petroleum Institute a pro- gram of education, training, experience, and/or examination assuring the manufacturer’s personnel are competent in weld- ing, inspection, nondestructive examination, and testing required or referenced by this specification.
5.2 WELDING PROCEDURE QUALIFICATION
The welding procedures shall be established in accor- dance with AWS D1.1. Written pre qualified welding proce- dures may be employed by the fabricator provided the procedure complies with all requirements (joint detail, filler metal, and so forth) for pre qualified status detailed in Appendix IV of AWS D1.1. More stringent Charpy V-notch toughness in the weld and/or heat affected zones than required in 5.1.3 above may be obtained, if desired, by spec- ification of Supplementary Requirement (SR2). The welding procedures shall be established in accor- dance with AWS D1.1. Written pre qualified welding proce- dures may be employed by the fabricator provided the procedure complies with all requirements (joint detail, filler metal, etc.) for pre qualified status detailed in Appendix IV of AWS D.1.1 More stringent CVN toughness in the weld and/or heat affected zones than required in Par. 3.3. above may be obtained, if desired, by specification of Supplemen- tary Requirement S2. The foregoing requirements shall apply separately to plate welds, pipe welds and girth welds.
Welding electrodes and fluxes shall conform to applicable AWS specifications and shall be selected to match the mini- mum ultimate strength of the base material, and to provide a minimum of 20 ft-lbs Charpy V-notch (CVN) impact energy at 0°F. Matching CVN toughness may be specified by invok- ing Supplementary Requirement S4. If the AWS specification requirement for the electrodes and fluxes to be employes is less than the foregoing, or if the welding procedure falls outside the range of essential vari- ables tested in the AWS specification, then Charpy test speci- mens shall be removed from a simulated production weld and tested in accordance with Annex III of AWS D1.1. The deposited weld metal shall possess an energy value not less than indicated. The foregoing requirements shall apply separately to the final condition of plate welds, pipe welds, and girth welds.