API SPEC 2B:2001 pdf download
API SPEC 2B:2001 pdf download.Specification for the Fabrication of Structural Steel Pipe.
Note: Ultrasonic inspection, as a supplementary requirement to the designated plate specification. may be specified, if desired. when structural steel pipe is to be used in the fibricatio,i of tubular joint cans in T. Y, and/or K connections where freedom from laminations and/or other internal defections is required.
5 Fabrication
5.1 GENERAL
5.1.1 Forming pipe furnished to this specification shall normally he formed below 4(X)°F, that is, cold formed. Warm forming (between 8(X)°F and 1200°F or 50°F below the tempering temperature of quenched and tempered steels) may he employed provided forming procedures for heat treated or TMCP steel are qualified to demonstrate the mechanical strength properties required by the original plate specification are met in the warm formed condition. Hot forming (above the upper critical temperature) may also he employed provided the forming procedure is qualified to demonstrate all mechanical properties required by the original plate specifications are met.
5.1.2 The purchaser may specify Supplementary Requirement I if the rolled direction of the plate is desired to he oriented in a specific direction during the forming of the pipe, and the pipe shall he so identified.
5.1.3 All welding shall he in accordance with AWS DI.l2000, Structural Welding Code—Steel. Unless otherwise approved by the purchaser, the submerged arc welding process shall he employed for all welding—except tack welds, root passes and repair welding where other AWS approved processes may he utilized. All welds shall he complete joint penetration groove welds produced by employing AWS Dl.l prequalified joint details, or other joint configurations qualifled by procedure qualification testing.
Welding electrodes and fluxes shall conform to applicable AWS specifications and shall he selected to match the minimum 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 he specified by invokI ng Supplementary Requirement S4.
If the AWS specification requirement for the electrodes and fluxes to he employes is less than the foregoing, or if the welding procedure falls outside the range of essential variables tested in the AWS specification, then Charpy test specimens shall he removed from a simulated production weld and tested in accordance with Annex III of AWS Dl.l.
5.2 WELDING PROCEDURE QUALIFICATION
The welding procedures shall he established in accordance with AWS D 1.1. Written pre qualified welding procedures may he employed by the fabricator provided the procedure complies with all requirements (joint detail, tiller metal, and so forth) for pre qualified status detailed in Appendix IV of AWS D I. I. More stringent Charpy V-notch toughness in the weld andlor heat affected zones than required in 5.1.3 above may he obtained, if desired, by specification of Supplementary Requirement (SR2).
The welding procedures shall he established in accordance with AWS Dl. 1. Written pre qualified welding procedures may he 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 Supplementary Requirement S2.
The foregoing requirements shall apply separately to plate welds, pipe welds and girth welds.
5.3 WELDER AND WELDING OPERATOR QUALI FICATION
Welders and welding operators shall be qualified in accordance with AWS D1.I, Chapter 4, Part B or C, as applicable. Radiography is acceptable for the qualification of submerged arc machine operators.
5.4 LONGITUDINAL WELDS
Radial offset of abutting edges of longitudinal weld seams shall not exceed 1/8 in. For LWDS pipe, no two longitudinal seams shall be closer together than one pipe diameter or 5 ft. whichever is greater. Longitudinal weld seams of adjoining cans shall be staggered as shown below, unless closer spacing is agreed upon by the purchaser and the fabricator.
