* The maximum allowable Manganese content is that listed in Table 3.1 of API 5L Table 2B. Manganese content increases based on carbon content are not permitted.
If the purchase order Data Sheet states that the pipe will be induction bent, the Supplier should ensure the appropriate base metal and welding consumable compositions are chosen to achieve the specified mechanical properties after bending.
3.0 Mechanical Properties and Tests
The mechanical properties should meet the requirements of API 5L, PSL 2.
For submerged arc welded pipe, Charpy impact tests should be performed on the weld metal and the heat affected zone. The Supplier should submit a procedure as part of the information requested in paragraph 4.1.1 for removing and notching the specimens.
For electric welded pipe, Charpy impact tests should be performed on the weld fusion line. The Supplier should submit a procedure as part of the information requested in paragraph 4.1.1 for removing and notching the specimens.
4.0 Nondestructive Inspection
A lamination check should be made over the whole circumference on each end of each pipe for a distance of one-inch (25 mm) from the end using a calibrated compression wave ultrasonic procedure approved by Buyer. The calibration should be done at the same frequency as the body inspection NDE units.
Additional Requirements for Submerged Arc Welded Pipe
- Nondestructive testing for final acceptance should be performed on the SAW weld seam after hydrotest and cold expansion per the requirements of API 5L, paragraphs 9.7.2 and 184.108.40.206, except as noted herein.
- A radiological inspection using the X-ray method for a minimum distance of eight inches from each pipe end is required in accordance with API 5L, paragraph 220.127.116.11 through 18.104.22.168.
- A full length ultrasonic inspection of each pipe is also required per API 5L, paragraph 22.214.171.124 through 126.96.36.199.
- The NDT reference standard for ultrasonic testing should be per API 5L, paragraph 188.8.131.52, except that it should contain OD and ID longitudinal and transverse notches and a 1/8-inch drilled hole. Unless otherwise specified, N10 notches are required for the reference standard.
Additional Requirements for Electric Welded Pipe
- Nondestructive inspection for final acceptance should be performed on the EW weld line after hydrotest per the requirements of API 5L, SR 17, except as noted herein.
- For pipe wall thickness less than or equal to 0.188 inches, either the ultrasonic NDT method or the electromagnetic NDT method (utilizing the diverted flux) should be used. For pipe wall thickness greater than 0.188 inches, the only acceptable method is the ultrasonic method.
- The NDT reference standard should contain both OD and ID longitudinal notches and a drilled hole. Unless otherwise specified, N10 notches and a 1/8-inch diameter hole are required for the reference standard.
5.0 Workmanship, Visual Examination, and Repair of Defects
Repairs to welded pipe should be in strict accordance with API Specification 5L with the following additional requirements:
- Repair welding is not permitted outside the weld zone.
- Multiple repairs of the same location are not permitted.
- Repaired areas should be nondestructively inspected by radiography onto suitable film or by manual ultrasonic inspection.
- Repair welding procedures should be qualified according to Appendix B of API Specification 5L.
- Repair welding procedure qualifications should include hardness traverses on a metallographic cross section of the weld at 2-3 mm below the cap pass and at 1-2 mm above the root. Each traverse should include readings at a maximum of 1 mm intervals in the base metal, HAZ, and weld metal (at least three readings in each zone) on both sides of the weld. No values should exceed 250 HV10. The composition of the deposited weld metal should not exceed 1% Ni for all repair welds.
6.0 Pipe Marking
Pipe number should be traceable back to coil or plate.