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Job Knowledge

Helpful articles with information about welding processes.

A Comparison of BS EN 287 Part 1.2011 with BS EN ISO 9606: Part 1

ISO 9606 Part 1 was published in November 2013 and replaces EN287 Part 1 which will be withdrawn in October...

Thu, 18 May 2017

A comparison of ISO 15614 Part 1 and ASME IX

The two most frequently encountered specifications are ISO 15614 Part 1 and ASME IX and whilst these are written with...

Tue, 20 October 2015

A general review of geometric shape imperfections - Part 1

Looks at those imperfections related to poor geometric shape, particularly excess weld metal (reinforcement), undercut, overlap (cold lapping), linear misalignment,...

Mon, 19 October 2015

A review of the application of weld symbols on drawings - Part 1

Introduces weld symbols according to BS EN 22553

Thu, 19 November 2015

A review of the application of weld symbols on drawings - Part 2

Presents example of symbols used on weld drawings to indicate the location, type, size etc of welds required, welding process...

Mon, 19 October 2015

A review of the causes and acceptance of shape imperfections

Covers causes, avoidance and acceptance criteria for imperfections in butt and fillet weld bead shape: excess penetration, root concavity, excess...

Mon, 19 October 2015

Air Carbon Arc Gouging

The principles of air carbon arc gouging are outlined including applications, electrodes, power sources, air supply, problems of carbon pick-up,...

Mon, 19 October 2015

Application Standards, Codes of Practice and Quality Levels

The requirements for standards on welding procedure and welder approval are explained together with the quality levels for imperfections. (Nov.1998)

Mon, 19 October 2015

Base metal grouping system

Job Knowledge 140: Base metal grouping system

Thu, 30 June 2016

Bend Testing

Bend testing is introduced as a simple and inexpensive qualitative test for evaluating the ductility and soundness of a material.

Tue, 19 September 2017

Braze Welding

The braze welding process is a variant of the MIG/MAG welding process, where the majority of the process-essential variables are...

Mon, 19 October 2015

Butt Fusion Welding of Plastics

Butt fusion welding of plastic pipes is described concisely, including tips for a successful weld, machine set up, aligning and...

Wed, 22 March 2017

Calculating Weld Volume and Weight

Calculating the volume of a weld is one of the first steps to be taken when estimating the cost of...

Tue, 20 October 2015

Ceramics - Materials, Joining and Applications

The characteristics of ceramics as engineering materials, industrial applications and factors affecting selection of joining processes are described

Mon, 19 October 2015

Compact Tension and J Integral Tests

Characterisation of fracture behaviour by the compact tension (CT) and the J integral tests is described. Test piece form, test...

Mon, 28 November 2016

Comparison of the use of Rutile and Cellulosic Electrodes

Many types of manual metal arc (MMA) electrodes are available on the market. Depending on the main constituent of their...

Thu, 11 May 2017

Complying with NACE Hardness Requirements

Carbon steels in service in the offshore and oil refinery industries are susceptible to a cracking mechanism known as...

Thu, 09 June 2016

Copper-nickel Alloys

Although there is a wide range of alloys, only two are commercially significant. These are the 90/10 and 70/30 grades...

Tue, 20 October 2015

Creep and Creep Testing

An article on creep and creep testing. Creep is a slow failure mechanism which may occur in a material...

Mon, 19 October 2015

CTOD Testing

Explains what CTOD testing is and how it's performed to provide quantitative measurement of fracture toughness

Mon, 19 October 2015

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