Forged steel valves are used for the industrial pipelines in the petroleum, chemical, metallurgy, machinery, shipbuilding, electric power and military industries and can be used to control the flowing of air, water, steam, mud, oil, liquid metal, radioactive media, all kinds of corrosive media and other types of fluid. Compared with other
valves,
forged steel valves have the characteristics of high temperature resistance, high pressure resistance and unique self-sealing design. The higher the pressure is, the more reliable the sealing of the forged steel valves will become. The performance characteristics, the technical characteristics as well as the special conditions of forged steel valves make them have advantages which can not be substituted for other products'.
Forged steel valves can be classified as forged steel check valves, forged steel gate valves,
forged steel ball valves, forged steel globe valves, self-sealing gate valves, self-sealing shut-off valves, self-sealing check valves, forged needle valves, etc.
Forged steel valves are mainly applicable to the corrosive media such as water vapor, oil and nitric acid. When the media are flowing, they can cause wear, rinse and cavitation for the sealing surfaces of valves, so the sealing surfaces of valves must be processed with good quality in order to make the valves still operated normally under the alternating effects of rinse and chemical erosion.
Special attention need paying to the discharging and pressure relieving problems of
forged steel valves. After the pressure test of the valve, the pressure of the gas and moisture in the valve's sealed cavity rises due to the increasing environments' temperatures, so drain contamination and decompression need to be done first before injecting grease, which is conducive to the smooth operation of injecting grease.
The imbalance between the upper and lower pressure in the opening and closing processes of forged steel valves will bring inconvenience for the operation of valves. Thus, in order to make the valves work properly and smoothly, the upper and lower pressure need to be balanced.