Cobalt Alloy are one of the commonly used materials for surfacing valve seals. Cobalt alloys have good high temperature properties, excellent heat strength, corrosion resistance and thermal fatigue resistance, especially in the hot state. Therefore, it is commonly used to surfacing the critical or supercritical parameters of the steam valve, as well as the valve sealing surface with relatively harsh conditions and high requirements for anti-wear and corrosion resistance. The excellent properties of cobalt alloys have made them extremely widely used in aerospace, aerospace, nuclear, power, petrochemical, metallurgy, transportation and machinery.
Due to the excellent physicochemical properties of Cobalt Alloy Valve Seat , it has been widely used in the valve industry. In order to standardize their use, countries have standardized on commonly used cobalt alloys.
At present, the surfacing welding cobalt alloy of the valve industry mainly adopts electric welding electrode surfacing, wire feeding plasma surfacing, manual tungsten argon arc welding, powder plasma arc surfacing, oxyacetylene flame surfacing, surface spray welding and the like. Due to the different dilution rates of the various processes for the wood, the composition of the resulting weld layer is also different.
The above-mentioned six kinds of process methods reduce the dilution effect of the base material in the order described. Oxyacetylene flame surfacing and surface spray welding have almost no dilution of the substrate. When surfacing the wear layer, the process method should consider the structure of the product and the possibility of its specific implementation. For example, in the case of small diameter and deep hole surfacing, manual arc welding can only be used. Other processes are not possible because of the space occupied by the tool. The workpiece is large, heating is difficult, and the surfacing process needs to continue to be heated. Sometimes it is impossible to operate, and oxyacetylene flame surfacing and surface spray welding cannot be used.