<p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">密封面是<strong>阀门</strong>*关键的工作面，密封面质量的好坏直接影响着阀门的使用寿命，面密封面的材料又是保证密封面质量的重要因素。因此，选择阀门密封面材料时应考虑如下因素：</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>①</span><span>耐腐蚀。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>“</span><span>腐蚀</span><span>”</span><span>即密封面在介质作用下，表面受到破坏的过程。如果表面受到这种破坏，密封性就不能保证，因此，密封面材料必须耐腐蚀。材料的耐腐蚀性主要取决于材料的万分及其化学稳定性。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>②</span><span>抗擦伤。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>“</span><span>擦伤</span><span>”</span><span>即密封面相对运动过程中，材料因摩擦而引起的损坏。这种损坏必然引起密封面的破坏，因此，密封面材料必须具有良好的抗擦伤性能，尢其是闸阀。材料的抗擦伤性往往是由材料内部性质决定的。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>③</span><span>耐冲蚀。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>“</span><span>冲蚀</span><span>”</span><span>即介质高速流经密封面时，使密封面遭到破坏的过程。这种破坏在高温、高压蒸汽介质中使用的节流阀、安全阀更为明显，对密封性破坏影响很大，因此，耐冲蚀亦是密封面材料的重要要求之一。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>④</span><span>应有一定的硬度，并在规定工作温度下硬度下发生大的下降。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>⑤</span><span>密封面和本体材料的线膨胀系数应该近似，这对镶密封圈的结构更为重要，以免高温下容易产生额外的应力和引起松动。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　<span>⑥</span><span>在高温条件下使用，要有足够的抗氧化、抗热疲劳性以及热循环等问题。</span></span><span style="font-family:'Times New Roman';font-size:10.5pt;"></span> </p> <p class="p0"> <span style="font-family:'Times New Roman';font-size:10.5pt;">　　</span> </p>