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不锈钢法兰形式不同，要求使用的垫片也不同。光滑面法兰一般只用于低压，配软质的薄密封垫；在高压下，如果法兰的强度足够，也可以用光滑面法兰，但应该用厚软质垫，或者用带内加强环或加强环的缠绕密封垫。在这种场合，金属垫片也不适用，因为这时要求的压紧力过大，导致螺栓较大的变形，使法兰不易封严。如果要用金属垫片，则应将光滑面缩小，使其与垫片的接触面积减小。这样，在螺栓张力相同的情况下，缩小后的窄光滑面的压紧应力就会增大。
齿轮泵密封垫的选用原则是，对于要求不高的场合，可凭经验选取，不合适时再更换。但对于那些要求严格的场合，例如易爆，剧毒和可燃气体以及强腐蚀的液体设备，反应罐和输送管道系统等，则应根据工作压力，工作温度，密封介质的腐蚀性及结合密封面的形式来选用。一般来说，在常温低压时，选用非金属软蜜密封垫；中压高温时，选用金属与非金属组合密封垫或金属密封垫；在温度，压力有较大的波动时，选用弹性好的或自紧式密封垫；在低温，腐蚀性介质或真空条件下，应考虑具有特殊性能的密封垫。这里需要说明的是法兰情况对垫片选择的影响。法兰表面粗糙度的影响。法兰表面粗糙度对密封效果影响很大，特别是当采用非软质垫片时，密封表面粗糙的度值大是造成泄露的主要原因之一。
Different flange form, requires the use of gaskets are also different. Flange generally smooth surface for low pressure, with a thin soft gasket; at high pressure, if the flange of sufficient strength, smooth surface can also use the flange, but it should be soft with a thick pad, or use in-band to strengthen ring or enhance wound gasket ring. In such cases, the metal gasket does not apply, because then the pressing force required is too large, resulting in greater deformation of bolts, so difficult to seal flange. If you use metal gaskets, smooth surface should be reduced, to reduce the contact area with the pads. Thus, under the same bolt tension, reduce narrow smooth surface after the compressive stress will increase. Gear pump gasket selection principle is, for less demanding situations, can be empirically selected, and then replaced when inappropriate. But for those demanding situations, such as explosive, toxic and flammable gases and highly corrosive liquid device, the reaction tank and pipeline systems, should be under the working pressure, temperature, corrosive media and the combination of sealing the sealing surface Selection form. In general, low pressure at room temperature, the use of soft honey non-metallic gasket; in pressure at high temperatures, use combinations of metal and nonmetal or metal gasket seals; in temperature and pressure fluctuations are larger, use a good flexibility or self-tight seals; at low temperature, corrosive media or vacuum conditions, performance should be considered a special gasket. It should be clear is that the situation on the flange gasket Choice. Flange surface roughness. Flange sealing surface roughness effects on the great influence, especially when the use of non-soft gasket, the sealing surface roughness is caused by a large degree the value of one of the main leak.