Welder Qualification and Welding Procedure Qualification
Laboratory Testing Inc. offers independent, third-party weld testing and welder qualification services for welder certification and welding procedure qualification. All of the required weld testing and inspections are available to verify that the weld procedure was followed properly, correct filler material was used and the weld joint is aligned accurately.
Laboratory Testing is a full-service weld test and welder qualification provider with complete in-house resources to turn your order around quickly and reliably. LTI’s full scope of capabilities include the following:
- Welder Qualification Testing for performance qualification and welder certification to ASME, ANSI, AWS and API code and Military standards
- Preparation of Welding Procedure Qualification as per client or project requirements
- Documentation of the Welding Procedure Qualification in a Certified Test Report as per ASME, ANSI, AWS and API code and Military standards
- Coupon Testing as per Welding Procedure Qualification which includes visual examination, mechanical testing, metallographic examination and nondestructive testing
LTI’s staff includes chemists, engineers and certified NDT inspectors, including Level II inspectors in Visual Examination. The full-service Machine Shop can prepare any size weld coupon, and runs two shifts to process orders under tight deadlines.
Weld Test Processes
Many types of testing are performed on welds and meet industry standards for welder qualification and welding procedure qualification, including these below:
The macroetch exam is typically performed on a finely ground cross-section taken transverse to the weld axis that has been etched with a chemical reagent to distinguish the weld, heat affected zone (HAZ), and base metal areas. Examination for characteristics such as weld size, fusion, penetration, profile, and weld discontinuities is performed at magnifications anywhere between 1X and 50X. Various AWS, ASME, military, and customer specifications call for macroetch examination.
The weld test for hardness evaluates the strength of the weld and is performed on a ground and etched sample, similar to the macroetch specimen. The most commonly employed scale for weld testing at LTI is the 10 Kg Vickers. This generally involves checking the hardness in all three zones, including weld , HAZ and base according to a pattern prescribed by the referenced specification. Hardness testing of welds is an extremely common practice and requirement in the oil and gas industry. One of the most commonly encountered specifications being NACE MR0175 / ISO 15156, and or a company-specific derivation.
Ferrite examination by the point count method and feritscope are performed to determine the amount of ferrite present in the weld metal, HAZ and/or base metal. The point count test is performed on a polished and etched cross-section of the sample per the point count method described in ASTM E562 or a company-specific derivation. The point count test is typically applied only to welds that involve the duplex stainless steels. Ferrite examination by feritscope is a nondestructive test performed with a contact probe that calculates ferrite via electro-magnetic response. This test is typically applied to welds that involve the austenitic steels.
LTI’s Chemistry Lab analyzes weld overlays as well as raw materials using various methods that include dilution analysis for overlays and Inductively-Coupled Plasma Spectroscopy (ICP) and Atomic Emission Spectroscopy (AES) for raw materials. The weld dilution test is used in weld qualification and involves dilution of the weld metal by the base metal following procedures to perform the test at specific distances from the base metal. The weld metal analysis is usually performed to AWS or ASME Part C specifications.
Nondestructive and Mechanical Testing
LTI offers Visual, Liquid Penetrant, Magnetic Particle and Radiographic Inspection for nondestructive evaluation. These tests are usually done in conjunction with applicable mechanical testing such as tensile, bending or impact testing according to the same specifications.
Weld Testing Methods for Welder Qualification
- Vickers Hardness Testing
- Ferrite Exam –Point Count and Feritscope
- Dilution Analysis
- Inductively-Coupled Plasma Spectroscopy (ICP)
- Atomic Emission Spectroscopy (AES)
- Tensile Testing
- Guided-Bend Tests – Plunger Type and Wrap Around Bends
- Charpy Impact Testing
- Drop Weight Testing
- Nick Break Tests
- Push Out Tests
- Peel Tests
- Section Tests
- Hardness Testing
- Fracture Toughness
- Visual Examination
- X-ray/Radiographic Inspection
- Magnetic Particle Inspection
- Liquid Penetrant Testing