Welding procedures and its qualifications..

Welding is one of the most critical operations within construction of equipment. Over the past sixty years of developments in welding technology, the current expectation of weld quality has never been higher. Ensuring good quality welding forms an important part of manufacturing. To ensure quality one of the primary step is to have qualifications for the welding process employed and qualified welders to be used for production.

In Third Party Inspection (TPI) we do inspection of different products.

From a Project prospective some of the major products and materials that we inspect and certify are pressure vessels, columns, heat exchangers, valves, pipes, tubes, fittings, flanges, gaskets, fasteners and foundation bolts etc. All these products involve welding as a production activity to build the product / manufacture the item component / assembly.

In TPI we do Procedure Qualification Record (PQR) and Welder Performance Qualification (WPQ – Welding performed by welder by manual arrangement) this is called WPQ or WOPQ (Welding Operator Performance Qualification – Welder performing welding with the aid either a semi- automatic or fully automatic arrangement).

Welding procedure qualification shall be based on a Welding Procedure Specification (WPS). As the name implies the WPS is a document developed based on the contractual requirements and reference construction code/ Welding Code. Procedure Qualification Record is the record of actual achieved values of welding of a test plate or pipe where all of the contractual requirements and reference code are met with modifications or without modifications – sometimes even with repeats or retesting.

Contractual document can be the PO, Drawing, Specification etc. Such Welding Qualifications are carried out with different welding process, a few listed below:

The reference code can be

• American Society of Mechanical Engineers (ASME) Codes
• American Welding Society (AWS) Standards
• American Petroleum Institute (API) Standards
• Australian / New Zealand (AS/NZS) Standards
• Canadian Standards Association (CSA) Standards
• British Standards (BS)
• International Organization for Standardization (ISO) Standards
• European Union (CEN) standards
• German Standards (DIN and others)

A few familiar reference code for ready reference

ASME Sec IX

A few ISO standards are ISO 15609, ISO 15614, ISO 9606

American Welding Society (AWS D1.1, D1.2, D1.3 …)

API RP 582 – American Petroleum Institute – Recommended Practice

API 1104 

Below link can be referred for more welding codes 

https://en.wikipedia.org/wiki/List_of_welding_codes

Such qualifications can also be carried out by applying a combination of more than one reference standard / welding codes and with customer specific requirements.They are required in diverse industries across sectors fabrication, manufacturing, automobile, space, production houses etc.  Many of the project site activity starts with such welding qualification for the project to kick start.

From a plant construction(green field or brown field) or maintenance prospective as well such qualifications are necessary. Its shall be interesting to note they are also required for different material of construction like Carbon Steel, Stainless Steel, Alloy steel, Nickel, Aluminium Titanium, Tantalum, Zirconium and so on.  Some of the products carried form such qualifications are sheet, plate, pipe, tube, castings (cosmetics and surface improvements under certain conditions) forgings and combination of these product form.

Some examples are :

• Sheet to Sheet
• Plate to Plate
• Plate to Pipe
• Pipe to Pipe
• Plate to Forgings
• Castings to Forgings
• Forging to forging
• Castings to Castings 

In the industry skilled qualified welders are on demand and many stake holders are looking for a Third Party Inspection Agency (TPIA) to establish qualifications for their welding processes and welders. TUV India helps its customers in establishing such qualifications for the different welding processes and welder qualifications.