WELD TESTING
WELDER QUALIFICATION AND WELDING PROCEDURE QUALIFICATION
Zhejiang Guojian Testing Technology Co., Ltd (CCT) offers independent, third-party weld testing services for Welder Qualification and Welding Procedure Qualification. Welding procedures are usually developed in accordance with a welding code or standard that requires weld samples be produced, inspected, and tested to establish qualification.
SCOPE OF OUR SERVICES FOR WELDING CERTIFICATION
Zhejiang Guojian Testing Technology Co., Ltd (CCT) is a full-service material testing provider with complete in-house resources to turn your order around quickly and reliably.We are located in zhejiang,China
Zhejiang Guojian Testing Technology Co., Ltd (CCT) performs destructive and non-destructive weld testing to verify that a welding procedure and welds produced according to the procedure meet requirements. The requirements are generally stated in standards and specifications, including GB, API, ASME, ASTM, AWS, EN
All required testing services are available to verify that a welding procedure meets requirements for qualification and to certify that a welder can properly produce a weld to specification. Welding coupons and specimens are also prepared onsite in our machine shop. The results of all qualification testing are documented in certified reports.
Welding Procedure Qualification
The welding procedure is reviewed in detail, then testing and inspection is performed on welds produced in accordance with the procedure to verify all requirements are met. Weld coupon testing often includes visual examination, mechanical testing, metallographic examination and nondestructive testing.
WELD TEST METHODS FOR QUALIFICATIONS
Many types of destructive and non destructive weld testing techniques are performed to verify conformance to specifications during welding qualifications, including these below:
METALLURGICAL TESTING
· Macroetch
· Vickers Hardness Testing
CHEMICAL ANALYSIS
· Dilution Analysis
· Inductively-Coupled Plasma Spectroscopy (ICP)
· Atomic Emission Spectroscopy (AES)
CORROSION TESTING
MECHANICAL TESTING
· Tensile Testing
· Guided-Bend Tests and Wrap Around Bends
· Charpy Impact Testing
· Section Tests
· Hardness Testing
· Fracture Toughness
NONDESTRUCTIVE TESTING
· X-ray/Radiographic Inspection
· Magnetic Particle Inspection
· Liquid Penetrant Testing
· Ultrasonic Testing
The full-service Machine Shop can prepare any size weld coupon, and runs two work shifts to process orders under tight deadlines.
WELD TESTING PROCESSES
Macroetch Exam
A macroetch examination is a process where a finely ground cross-section of a material is taken transversely to the weld axis and is treated with a chemical reagent to differentiate between the weld, heat affected zone (HAZ), and base metal areas. This examination allows for the evaluation of characteristics such as weld size, fusion, penetration, profile, and the presence of weld discontinuities at magnifications ranging from 1X to 50X. Macroetch examination is required by various standards such as AWS, ASME, military, and customer specifications.
Hardness Testing
The weld hardness test is conducted to determine the strength of a weld and involves examining a ground and etched sample, similar to the macroetch specimen. At Zhejiang Guojian Testing Technology Co., Ltd (CCT) , we typically use the Vickers scale for weld testing. The test involves checking the hardness in all three zones, namely weld, heat affected zone (HAZ), and base metal, according to a pattern specified in the relevant standard.
Ferite Examination
Ferrite examination is an important test in evaluating the quality of welds, especially for stainless steel. Ferrite is a form of iron that can have a significant impact on the performance of a weld. The amount of ferrite present in a weld can affect its strength, corrosion resistance, and other properties.
The point count method is a common technique for ferrite examination in duplex stainless steels. It involves a polished and etched cross-section of the sample, where a grid is overlaid on the cross-section and the ferrite phase is counted at each intersection point. The results are expressed as a percentage of the total area examined.
The feritscope is a non-destructive technique for ferrite examination in austenitic steels. It uses a contact probe that calculates ferrite via electro-magnetic response. This method can be used to quickly determine the ferrite content of a weld without the need for sample preparation.
Both techniques can provide important information about the quality of a weld and can help ensure that the weld meets the required specifications.
Chemistry
.Dilution analysis is a method used to determine the amount of base metal and filler metal in a weld overlay. This information is important in ensuring the proper composition and quality of the weld. Inductively-Coupled Plasma Spectroscopy (ICP) and Atomic Emission Spectroscopy (AES) are two common methods used to analyze the chemical composition of raw materials, including the base metal and filler metal used in welding.
Performing chemical analysis on welds and raw materials is critical in ensuring compliance with industry standards and specifications, such as those set by AWS or ASME Part C. By using the appropriate testing methods, Zhejiang Guojian Testing Technology Co., Ltd (CCT) 's Chemistry Lab can accurately determine the composition of materials and ensure that they meet the required standards.
Nondestructive and Mechanical Testing
Zhejiang Guojian Testing Technology Co., Ltd (CCT) provides non-destructive evaluation services such as Liquid Penetrant Testing (LPT), Magnetic Particle Testing (MPT), Visual Inspection (VI), Ultrasonic Testing (UT), and Radiographic Inspection (RT). These techniques are widely used in various industries, including aerospace, automotive, construction, and manufacturing, to assess the integrity of materials and structures without causing damage.
To ensure a comprehensive evaluation, mechanical testing such as tensile, bend or impact testing is often performed in conjunction with NDT according to the same specifications. These mechanical tests measure the material's response to external forces and provide valuable information about its mechanical properties, including strength, ductility, and toughness.
