DT & NDT specifying for PQR

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WPS/PQR Qualification

The WPS for both the main welding procedures and weld repair procedures an oil and gas project shall be submitted by CONTRACTOR to Client / COMPANY normally one month minimum before the point of qualification tests.

The WPS shall be accompanied by a summary table showing: process, consumables, direction of welding, type of weld, WPS no., test weld wall thickness and scope of qualification. The welding procedure qualification tests shall not be undertaken until the COMPANY Inspector (COMPANY’S authorized representatives or members) has given his approval of the principle on the said WPS.

CONTRACTOR shall demonstrate by qualification tests that the proposed WPS as well as the equipment he intends to use enable performance of welds and weld repairs meeting the quality and properties required in this specification. Welding procedure qualifications shall be required for pipe to pipe welds but also for all other welds including fillet welds, fittings to pipes, fittings to fittings and all associated weld repairs.

  • The test welds shall be fully visually inspected and then non-destructively tested.
  • All welding procedure qualification tests shall be conducted in the presence of the COMPANY Inspector.
  • COMPANY shall give final acceptance and approval of all welding processes, systems and procedures.
  • The COMPANY Inspector shall witness all non-destructive examinations and destructive testings and shall review and approve all related results. All mechanical testings shall be carried out by a certified testing facility subject to prior approval of the COMPANY.

Mechanical Properties Test

The amount of deformation which metal can withstand under different modes of force application

  • Mallability : of a material to withstand deformation under static compressive loading without rupture
  • Ductility : ability of a material undergo plastic deformation under static tensile loading without rupture. Measurable elongation and reduction in cross section area
  • Toughness : ability of a material to withstand bending or the application of shear stresses by impact loading without fracture.
  • Hardness : Measurement of a materials surface resistance to indentation from another material by static load
  • Tensile Strength : Measurement of the maximum force required to fracture a materials bar of unit cross-sectional area in tension

Tests for required properties

  • Tensile tests (Transverse Welded Joint, All Weld Metal)
  • Toughness testing (Charpy, Izod)
  • Hardness tests (Brinell, Rockwell, Vickers)
  • Bend testing
  • CTOD (Crack Tip Opening Displacement)
  • Corrosion tests, HIC & SOHIC Tests (NACE)

Tests for weld quality

  • Macro testing
  • Fillet weld fracture testing
  • Butt weld nick-break testing
  • NDE (VT,PT,MT,RT,UT)

Codes, Standards and Customer Specifications/Requirements

For example, the following is a summary of the code / standard / specification / requirements that must be learned before attending the mechanical tests in laboratory testing for WPS / PQR qualification for piping / pipeline / structural system an oil and gas project.

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There’re many requirements for qualification of PQR/WPS, specially in offshore oil & gas project.

Hereby the experienced data through my career for your reference as a map of checklist:

PQR CHECKLIST

 

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