Production welds in STELEX INDUSTRIES are done following qualified WPS and approved QAP. Welding process and welding quality at all stages during manufacturing as per acceptance criteria specified in the technical specification (TS) approved drawings, WPS and approved QAP. For information general checks stages of welding are indicated below.
Checking of cabling voltage & current output of welding equipment as per requirement of the job. Raw materials preparation i.e., circularity, flatness straightness of the components to be welded. Edge preparation & joint fit-up i.e., angle, gap etc, as pr approved drawings. Checking of re-drying of electrodes as required. Pre-heating temperature of a job as per qualified WPS. If any. Also preheating checked by thermo pen
Controlling inter-pass temperature as per WPS. Peening of heat affected zone (except root run final weld run) for relieve of residual stress. Root-pass Grinding/Back gouging. Dye penetration test, if required as per Qualified WPS. Checking of weld-heads by wire brushing/chipping/grinding. For individual fabricated and welded jobs, WPS is prepared as per ASME-SEC-IX/AWS D 1.1 coded after approval of WPS by competent authority/client. Qualifying Tests are conducted on test samples prepared accordingly and PQR is maintained for the same. Competent authority of approval of WPS may be customer, if required as per contract of QC dept. of STELEX. Same WPS and PQR of butt welds/Fillet Welds in SMAW, SAW & GMAW process (Approved by are enclosed as per Annexure-3-1 To Annexure-3-XVI.
Visual checking of finished Welding as per acceptance criteria of approved QAP and removal/rectification of spatter, undercut, pinholes or other surface flaws weld contours and sizes are also checked. Final Welding Inspection (Visual) is to be checked as per Inspection parameter and procedure indicated in Annexure. NDE of weld joints viz. Radiography testing (RT) Ultrasonic testing (UT) etc, as requiredas per TC/approved QAP. Rectification of weld defects area, if any and rechecking by NDE method for Soundness. NDE of welding i.e. RT/UT/PT/MPT are all done by level-II qualified personnel as perrequirement of SNT-TC-IA of ASNT. Applicable procedure and acceptance standard of NDE of weld joints followed by STELEX INDUSTRIES as per Annexure-if not mentioned in TC/Approved drawing.