Anti-galling chrome plating
Surface Treatment
Composite films of chrome plating with high rigidity and high melting point and PTFE with excellent lubricity and friction resistance are used to prevent seizure and galling, improve operating efficiency, extend the service lives of parts, and reduce maintenance burden.
Anti-galling chrome plating
One of the metal wear types is adhesive wear. Adhesive wear tends to occur between metals of the same kind, on soft metals, or on metals with a low melting point. If adhesive wear becomes severe, it may result in galling or seizure, causing the metal parts to become stuck and stop sliding. For example, there are many cases where stainless steel nuts and bolts gall to each other, causing them to stop moving completely. Once galling occurs to a component, it may cause a serious problem such as failure to stop the functionality of the component completely, and it costs more than expected because of component replacement or some other measures to repair the problem.
If chrome plating is used in a dry state, it tends to seize when the mating material is chrome plating, tin, zinc, or bronze, and, conversely, chrome plating seems to be difficult to seize with copper. The table below shows the likelihood of seizure occurrences between different types of metal. Otec adopts composite films of chrome plating with high rigidity and high melting point and PTFE with excellent lubricity and friction resistance in order to prevent seizure and galling, improve operating efficiency, extend the service lives of parts, and reduce maintenance burden. This technique is different from our Tfe-Lok treatment and is a suitable treatment for nuts and bolts.
Likelihood of seizure occurrences between different types of metal
  Iron Aluminum Copper Silver   Iron Aluminum Copper Silver
Beryllium Iron -
Carbon × × × Cobalt
Magnesium × Nickel ×
Aluminum - Copper -
Silicon Zinc   -
Titanium Molybdenum ×
Chromium Rhodium  
Manganese - - - Palladium - - -
  Iron Aluminum Copper Silver
Silver -
Cadmium  
Tin -
Tungsten -
Platinum -
Gold
Lead -
         
◎: Do not melt into each other and difficult to seize to each other
○: Melt into each other but difficult to seize to each other
×: Do not melt into each other but easy to seize to each other
●: Melt into each other and easy to seize to each other
Round nuts for shutters