Frequent temperature fluctuations expose the valve to excessive stresses which cause surface cracks in the body bores of cast steel valves 频繁的温度波动使阀门承受着过度的压力,这种压力容易造成铸钢阀门阀体孔内部表面裂缝。
Hkv mainly produces api forged and cast steel valves , chinese standards high - medium pressure valves , forged flanges as well as piping assessories 华凯阀业主要生产api标准锻钢及铸钢阀门、国标高中压阀门、锻钢法兰及管道附件等。
Nibco ' s ductile iron multi - turn valves are ideal for a wide variety of services : hydrocarbons , chemical , marine , fire protection services , pulp and paper applications where cast iron and / or cast steel valves could be installed 美国尼伯科多转阀门非常适用于许多应用领域:烃类,化学制品,船舶,消防防火,纸浆和造纸等行业中可以安装铸铁或铸钢阀门的地方。