Understanding the 3 Common Weld Cleaners
January 11th, 2021 by Catherine Marqueses
Proper cleaning is critical when it comes to ensuring the success of a welding operation. It affects quality as a material surface with impurities and dirt can result in inclusions or problems, including porosity. Surface preparation and cleaning can also affect the overall look of the final and operation expenses for labour and rework.
There are many weld cleaners available on the market. The choice mainly depends on the operator’s preference and application requirements. Each weld cleaner offers a distinct purpose and performance. For instance, abrasive products are created to eliminate base material, while wire brushes do not provide the same function. Here are the three common weld cleaners on the market you should know about.
Bonded abrasives or grinding wheels
If the weld has porosity or slag inclusions, operators can use a grinding wheel for Interpass cleaning to eliminate some weld substances apart from eliminating the inclusion. These products are usually utilised for cleaning mild steel and sloppier welds that might have many spatter or slag as the wheels will remove more substances quicker.
Grinding wheels depend on a combination of the grain size, grain type, and bonding materials (additive fillers and resins) to define their performance. Since bonded abrasives are typically more aggressive and eliminate material much quicker, they require a higher operator skill level to avoid damage, undercutting, or gouging. Their application has to determine the wheel’s thickness; a thicker wheel is necessary to remove heavier material.
Coated abrasives or flap discs
Flap discs or coated abrasives are another common weld cleaner. They utilise similar types of gain as those in bonded abrasives. However, rather than presses and moulded into a hard grinding wheel, the gains are affixed to a backing cloth. The cloth is layered to create a flap disc, making the disc softer and giving off a more forgiving feel.
Operators can use the flap discs on stainless steel or on carbon or mild steel to remove the slight substance before weld cleaning. They can also use the flap discs for finishing the surface and blending after weld. Hence, they are a great choice when a finished item needs to be primed, painted or powder-coated.
Nonetheless, operators should be mindful of the spin direction when using the flap discs. Be sure they are spinning properly and throwing the debris and sparks away from the weld and base element and not back across them to prevent contamination.
Wire brushes and wheels
These products are a great option for post-weld and interpass cleaning, particularly when spatter and other contaminants removal are necessary. If the item has plenty of mill scale, heat discolouration, or rust to remove (without eliminating many materials), wire brushes will also work well before cleaning.
When selecting a power brush, operators can choose from many knot styles, trim length, and wire gauges options. They can fine-tune the brush performance for a particular application by modifying one or more of these traits. A stringer bead brush, for instance, has narrower knots that are spun from the base up to the tip, making them an ideal option for penetrating narrow spaces, such as fillets, corners, and root pass welds when cleaning.
Since the wire brushes’ tips are responsible for doing the job, operators have to use the right pressure to ensure efficiency and great performance. Using too much pressure may cause the wires to bend and flex, holding back the cleaning and result in wire breakage, which will decrease the brush life.
Welds and cleaning tools are an essential element of a welding operation. There is no one-size-fits-all solution when it comes to choosing brush, abrasive or wheels for weld cleaning. Hence, operators should understand each weld cleaner’s function and always evaluate the job’s requirements and priorities.