Welding certification

Welding Certificates and Weld Procedures No longer relevant after 20 or more years Typically held by the manufacturer... 

The International Association of Geosynthetic Installers (lAGI, www.iagi.org) has published a HOPE geomembrane installation specification and offers a HOPE welding certification program. 

It is particularly in the serial inspection of castings, that radioscopy constitutes state-of-the-art when applied in conjunction with systems for image intensification, digital image processing and automatic image evaluation. For the examination of welds, however, standardization is still non-existent, thus rendering more difficult the application of this inspection technique.As a consequence the approval procedures of the respective supervisory or certification boards are often complicated and of necessity set up for each individual case. 

Six certification centres are functioning in Ukraine at present in Kiev, Khar kov, Dmepropetrovsk, Zaporozhje, L vov and Ivano-Frankovsk The best known of them is the NDT Certification Centre at the E O.Paton Electric Welding Institute, which was the first one to receive, already in 1990, the licence of the USSR National Certification Committee for certification of the NDT experts. These certification centres have the right to grant levels I and II (according to EN 473), while level III can only be granted by the National Certification Committee. 

The Interbranch Educational Centre of Welding and Control and the Certification Centre on NDT, are functioning at the Institute... 

A certificate was attached to the exchanger stating that welding and burning were allowed but only to the shell. The contractor, having removed most of the tubes, decided to put workers into the shell to grind out the plugged tubes. He telephoned the plant and asked if it would be safe to let workers enter the shell. He did not say why he wanted them to do so. 

All aspects of the material s chemical, mechanical and physical properties which are included in the specification should be capable of measurement and certification. For critical duties all material supplied should be fully tested and certified by competent approved, independent test laboratories. All items of plant should be purchased with material certification. Additional certification is required in cases where the fabricator, in manufacturing an item of plant, used techniques such as welding or heat treatment which may affect the corrosion behavior of the construction materials. 

Christensen JM, Byrialsen K, Vercoutere K, Cornelis R, and Quevauviller Ph (1999) Certification of Cr(VI) and total leachable Cr contents in welding dust loaded on a filter (CRM 545). Fresenius J Anal Chem 363 28-32. 

The Standards, Measurements and Testing Programme of the European Commission launched a few years ago a project dealing with the development and, ultimately, the production of air filters realistically exposed to welding dust occurring during stainless steel welding (Christensen et al. 1999). This project resulted in the production and certification of a batch of 1100 filters for the Cr (VI) content (40.16 0.60 pg/g dust) (CRM 545). In addition, the total leachable Cr content ( 39.37 1.30 pg/g dust) was certified as a means to check for total Cr recovery. 

Regulated areas in the construction of a pressure vessel are (details depend upon the national code) design and calculation, permissible materials, quality control of materials, quality control of the fabrication processes (particularly welding), safety devices and -last but not least- full certification and documentation. 

Welding Filler Metal Wrong filler metal with poorer corrosion resistance (317L stainless steel) was used in alloy C-276 piping Product leakage at welds required shutdown and replacement of piping Check certification of weld filler metals used for field fabrication. For critical applications conduct chemical analysis on sample... 

Specific chapters then focus on different projects on speciation analysis. Chapter 4 deals with interlaboratory studies on methylmercury in fish and sediment Chapter 5 describes the collaborative projects to certify organotins in sediment RMs and mussel tissues Chapter 6 gives an overview of the certification project on trimethyllead in simulated rainwater and urban dust Chapter 7 describes the certification project on arsenic species in fish tissues Chapter 8 focuses on the intercomparison and tentative certification of Se(IV) and Se(VI) in simulated freshwater Chapter 9 deals with a feasibility study to stabilize Cr species in solution followed by the certification of Cr(III) and Cr(VI) in lyophilized solutions and welding dust Chapter 10 gives a review of methods used for A1 speciation Chapter 11 develops the overall collaborative project to standardize single and sequential extraction procedures for soil and sediment analysis, followed by interlaboratory studies and certification of soil and sediment reference materials. 

The interlaboratory study and certification campaign were coordinated by the Laboratorium voor Analytische Scheikunde, Universiteit Gent (Belgium), which also performed the preparation of the lyophilized solutions the filters loaded with welding dust were prepared by the Arbejdsmiljoinstituttet in Copenhagen (Denmark). 

Fig. 13.33 The Eclipse 500 business-class jet is currently in final Federal Aviation Administration certification trials (left). The internal longitudinal and circumferential aluminum stiffeners (top right) and window and door doublers (bottom right) are attached to the aluminum fuselage section with friction stir welded lap joints. Courtesy of Eclipse Aviation...

A knowledge of steel composition is essential for selecting the appropriate welding diagram. Where test certificates are available for the material to be welded, these should be consulted to determine the CE appropriate to the steel. Where this is not available, the specification for the steel, whether it be a national or international standard or a maker s specification, is helpful and increasingly these may provide data on the maximum CE values for particular grades. 

Final documentation for a validated manufacturing facility is critical to the success of the project. Documentation and certiflcation of the work is the responsibility of the construction management team. The format and items required for certiflcation should be included in both the design documents and the validation plan. Almost all documentation provided by vendors is available in electronic format. The computer design programs used to provide this documentation should be established in the early stages of the project and validation plan. The construction manager insures that the subcontractors and suppliers comply with these requirements. Weld documentation and instrument calibration are two of the most common certifications required of the contractors. 

Fabrication certification Once the certified material is obtained, the next step is fabrication where industrial processes such as machining, welding, and assembly are used to construct components, systems, and ships. OQE is used to document the industrial processes. Separately, and prior to actual fabrication of the final product, the facility performing the work is certified in the industrial processes necessary to perform the work. An example is a specific... 

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