SAE 316 stainless steel fittings are used in most of the toughest hydraulic applications because of their high corrosion resistance, especially at high temperatures. But some applications can push the limits of stainless steels.
SAE 316 stainless steel fittings are used in most of the toughest hydraulic applications because of their high corrosion resistance, especially at high temperatures. But some applications can push the limits of stainless steels.
SSP Fittings, Cleveland, recently adopted Expanite, a proprietary process to improve the corrosion resistance of their stainless steel components. However, the process also produces additional benefits. The lower friction exhibited by the finish means less make-up torque is needed for installation.
The Expanite feature uses a patented low-temperature process to saturate the spaces within the austenitic steel structure with carbon and nitrogen. The process transforms stainless steel by removing the primary passivation layer and replacing it with an outer layer saturated with nitrogen and an inside layer saturated with carbon. Hardening at low temperature allows gas saturation of the stainless steel structure without allowing chromium to migrate to form carbides. Filling the space between the austenitic structure hardens the surface. Preventing chromium from forming carbides prevents the dissolution of Chromium to maintain corrosion resistance.