API st 582:2001 pdf download
API st 582:2001 pdf download.Welding Guidelines for the Chemical, Oil, and Gas Industries.
6.4 DUPLEX STAINLESS STEEL WELDING
When welding duplex stainless steels, the following requirements shall apply:
6.4.1 Fcrritc numbcr for the weld procedure qualification and deposited weld metal shall be 30-70 FN as determined by an instrument calibrated to AWS A4.2.
6.4.2 lithe deposited weld nwtal ferrite content as shown in the procedure qualification record) is greater than (iO FN, the moisture content of duplex stainless steel electrodes shall be controlled to 02% maximum as measured by the test procedure given in AWS A5.5. Section 14.
6.5 SUBMERGED ARC WELDING
6.5.1 11w flux trade name and designation used for the procedure quaiification shall be specified in both the WPS and PQR.
6.5.2 Filler metal/flux combinations specified by the nianufacturer for single pass welding shall not be used for multi- pass welding.
6.5.3 Alloyed submerged arc fluxes shall not be used for welding low alloy sleds. Fluxes thai compensate for arc losses of alloying elements arc permitted.
6.5.4 Flux from re-crushed slag may be used only with approval of the purchaser.
6.6 CONSUMABLE STORAGE AND HANDLING
6.6.1 Welding consumables shall be stored and handled in accordance with the manufacturer’s instructions.
6.6.2 Storage and baking of welding consumables shall be carried out in a separate oven. The ovens shall be heated by electrical means and shall have automatic heat controls and visible temperature indication.
7 Shielding and Purging Gases
7.1 When shielding gases are used, the WPS shall indicate the shielding gas (or gas mixture. percent composition of gas(es) and flow rate.
7.2 Shielding gases shall meet the purity requirements of AWS 5.32. Gas purity should be recorded on the I’QR and WPS when a single gas is used.
7.5Whenever a back purging gas is selected to prevent oxi-dation or scale formation on the underside of the weld, thepurge shall be maintained until at least 1{4 in.(6.3 mm) depthof weld metal has been deposited.
8Preheating and lnterpass Temperature8.1 Preheating, where required, applies to all welding, tackwelding, and thermal cutting of ferritic steels except for ther-mal cutting of P1 materials.Minimum preheat requirementsshall follow the applicable code such as ASME Section Vm,Appendix R;ASME B31.3,Table 330.1.1; and AwS D1.1,Annex XL.Any recommendations or requirements for preheatlisted in the relevant code shall be considered mandatory.8.2The preheat temperature shall be applied throughout theentire thickness of the weld and at least 3 in. (76 mm) on eachside of the weld. The preheat and interpass temperature shallbe checked by use of thermocouples, temperature indicatingcrayons, pyrometers or other suitable methodls.
8.3The maximum interpass temperature shall be specifiedin the wPS and PQR for austenitic stainless steels，duplexstainless steels, and non-ferrous alloys and, when impact test-ing is required for carbon and low-alloy steels.
8.4Table 8-1 provides recommended maximum interpasstemperatures.
9Postweld Heat Treatment (PWHT)
9.1 Postweld heat treatment used for a PQR shall be inaccordance with a procedure based on the requirements of theapplicable code and purchase order. For production use, theheat treatment procedure shall be reviewed and approved bythe purchaser prior to PWHT.
9.2All wPS’s specifying PWHT should indicate the following.
