AWS defines welding procedure, as the detailed methods and practices including all joint welding procedures involved in the production of a weldment. It is very important that before starting to weld, a welding procedure is drawn up, which will ensure acceptable quality welds at the lowest overall cost. Procedures become more stringent and costly as […]

The four recognised positions of welding are: Flat or downhand, horizontal, vertical and over­head. They are shown in Fig. 8.20. The four sketches on the left refer to fillet welds made in the joints, while the four sketches on the right refer to butt welds. The angle and direction in which the electrode is held […]

Suitable for inside and outside corner joints provided there is no lamellar tearing. Also for horizontal-vertical position butt joints. Cheaper to prepare than asymmetric U for this purpose. g P t= 12-50 mm ^ a ^ a = 60° s = 0-1.6 g = 1.6-6.3 mm P g =10-15° b2 = 45 — 40° Asymmetric […]

— Welding procedures are discussed in chapter 2 on welding processes. — For new jobs, procedure is finalised after welding a few sample joints and subjecting them to the required tests. The aim is to produce a quality job at lowest possible cost. — Weldable steel should be selected as far as possible. — A […]

In many organisations, the design engineer expected to provide welding procedure sheets alongwith his designs. For this purpose he takes help from the welding engineering and the shop supervisor. To be a good designer he should have the knowledge of welding technology (welding processes, procedures and weldability of metals. He is advised to study this […]

As a production engineer and executive, a knowledge of “location of elements of a welding symbols” is necessary for indicating or interpreting. This will now be discussed in more details in the following paragraphs. Any of the following standards could be used depending upon the situation and case of use. 1. AWS-A24: Symbols for welding […]

An Engineer entering the field of welded design, usually has the background of mechanical or materials engineering, and has very little understanding of the factors that contribute to effi­cient welded design as welding technology and weld design are not regular subjects in engi­neering colleges. A successful welded structure design will: 1. perform its intended functions. […]

A. Hard Surfacing 1. Hard surfacing is the application of a durable surface layer to a base metal to impart properties like resistance to impact wear and erosion or pitting and corrosion or any combina­tion of these factors. Hard surfacing can be applied by arc welding. 2. Hard facing materials for wear resistance tend to […]

Dissimilar metals are commonly welded using fusion and pressure welding processes. The major Difficulties encountered are as follows : 1. Differences in physical and mechanical properties. 2. Dilution of deposited filler material. 3. Formation of intermetallic compounds at the interface causing embrittlement of the joint. To eliminate this or reduce, heat input to the weld […]

1. Austenitic grades are non-hardening type and welding usually does not adversely affect weld strength and ductility. There is one detrimental effect of heating of Ni-Cr steel i. e., carbide precipitation at the grain boundaries resulting in reduced corrosion resistance. A fine film of Cr-rich carbides containing upto 90% Cr taken from metal layer next […]