The Importance of Welding Pre-Treatments

January 25, 2016

STI Group is dedicated to providing the highest quality welding and fabrication services. All of our welds are rigorously tested for quality and safety. A major part of ensuring excellent weld quality begins before the welding process even makes contact with the work surface: welding pre-treatments.

Pre-Treatments Ensure a Safe Weld

When a welder does not properly clean the metal before welding it together, the result can be disastrous. Dirt, grime, and other surface impurities that are left in place will ultimately compromise the integrity of the weld. This is especially problematic in the industrial, fabrication, and construction sector because good quality welds are crucial for safety and are often used in structural components or to contain potentially volatile or dangerous materials. Pre-treatments ensure that the work surface is as clean as possible and help improve weld penetration and overall quality.

Proper Pre-Treatments Save Money

Setting aside the major financial toll a broken weld could cause if it results in an accident, spill, or facility outage, proper pre-treatment cleaning saves money in other ways. On the fabricator’s side of things doing the job right the first time reduces costs associated with re-doing a defective weld that is revealed in quality testing. Likewise if a weld that is not up to standard does get through testing, but is caught by the client, that could result in a loss of confidence in the fabrication and potential a loss of business. At best the weld will have to be fixed at greater expense than it would have cost earlier in the process. Finally, if the weld defect is not detected in testing or by the client it could still cause a premature wearing out of parts or equipment that will require repairs or replacements sooner than would have been necessary.

Pre-Treatments Make the Job Easier

When rust, dirt or other forms of corrosion build up on metal, it can make the process of welding more difficult. Ensuring the metal is properly cleaned before beginning the process of welding makes the job easier to complete and prevents having to start over to get a clean weld. Experienced welders know that while it might be tempting to jump right in and get started, taking the time to properly clean the work area will ultimately make their jobs easier.

About the Pre-Treatment Process

The pre-treatment process for welding will vary depending on the type of metal the welder is working with. The welder should first check the metal for any type of coating that could possibly cause non fusion or improper penetration into the base metal. If there is any indication of that, it has to be removed with a grinder and for some non ferrous materials by using chemicals. It is also important to remove rust and any not up to standard welds present on the workpieces. Finally, the welder should clean the edges of the pieces to be welded together with a grinder.

Pre-Treatments for Aluminum Welding

Pretreating aluminum is a bigger task. Not only does aluminum need to be free of dirt and other debris, but it also must be free of oxide. Both the base metal and its filler must be properly prepared when working with aluminum. Another consideration is proper storage. Storing aluminum pieces vertically and at room temperature can prevent the accumulation of water and condensation, keeping the aluminum sheets in better condition and minimizing pre-treatment requirements.

Importance of Proper Storage in Pre-Treatment

Proper storage of metals prior to welding is crucial. Metals, especially aluminum, should be stored in a clean, dry environment to minimize contamination and reduce the need for extensive pre-treatment. This step is vital for maintaining the integrity and quality of the weld.

Pre-Treatment Processes for Different Metals

Aluminum: Aluminum requires careful handling due to its susceptibility to contamination. The pre-treatment involves thorough cleaning to remove oils and oxides, often using chemical or mechanical methods.

Steel: For steel, pre-treatment typically involves degreasing and rust removal. This can be achieved through abrasive blasting or chemical cleaning to ensure a clean surface for welding.

Stainless Steel: Stainless steel pre-treatment focuses on maintaining the material’s corrosion resistance. Processes often include passivation and pickling to remove any free iron from the surface.

For more detailed information about this project, please visit the EPC Pipe Fabrication Project page.

At STI Group, our welders always take care to follow certified welding procedures and process which includes properly cleaning any metal we will incorporate into the welding fabrication process. All of our welds are visually inspected and non-destructive tested per client-specified requirements and national code standards. We are committed to providing our clients with nothing but top-quality, industry-leading welds and weldments.