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Quality & Safety in Welding Procedures with Metal 3D Printing Perspective
By Ir . Teo Eu Jin
Per definition , welding is a process whereby two or more parts , called “ parent material ”, are fused together via heat and / or pressure , forming a joint which is referred to as weldment . Some welding processes require consumables , while others do not , for example , “ resistance spot welding ”. Current available welding technology can be applied to metals , thermoplastics and even wood . Howbeit , utilising the welding process on steel material is still the most common in our industry today .
Many small and medium-sized fabricators in Malaysia treat welding as a simple manufacturing process without referring to specific codes or standards . Nonetheless , it all depends on the customer ’ s requirement and the needed Quality Assurance on the product .
So , how does one produce a weldment of reasonable quality meeting a specific standard ? The answer is by utilising a “ Welding Procedure Specification ” ( WPS ). WPS is a formal internal document used by welding companies to instruct their welders or welding operators on the method to achieve production weld that meets the relevant code requirement , and it is usually associated with quality .
Welding Procedure Quality Aspect
A good quality weldment can be long-lasting but it depends on various factors . To be repeatable , a systematic approach is used in qualifying the welding procedure and welder , referred to as
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Sample SMAW Process |
Sample Robotic GMAW Process |
There are multiple welding processes in our industry : Gas Tungsten Arc Welding ( GTAW ), Shielded Metal Arc Welding ( SMAW ), Gas Metal Arc Welding ( GMAW ), and Submerged Arc Welding ( SAW ) just to name a few . Furthermore , welding methods |
Source : Photo taken from Malaysia Fabrication Industry
A qualified welder using the manual SMAW process on a Carbon Steel Pipe-to-Flange joint connection .
Source : MIDA , “ Malaysia ’ s Machinery & Equipment and Engineering Supporting Industries ”, Jun 2020
Robotic Welding using the GMAW process on a particular product . The robotic arm can be classified as advanced technology , but the welding process itself remains traditional .
Figure 1 : Conventional Metal Fusion Method via Welding can range from the common Manual Technique to being Fully Automated ( e . g ., the robotic arm is basically an extension of a human arm and works according to the programmed motion in sequence ).
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