補(bu)(bu)償(chang)(chang)(chang)器習慣上(shang)也叫膨脹節(jie)，或(huo)(huo)伸(shen)縮(suo)節(jie)。由(you)構(gou)成其(qi)工(gong)(gong)作主(zhu)體的(de)波(bo)(bo)紋(wen)管(guan)(guan)(guan)(guan)（一(yi)種(zhong)彈性元(yuan)件）和(he)端管(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導管(guan)(guan)(guan)(guan)等附件組(zu)成。 屬(shu)于(yu)一(yi)種(zhong)補(bu)(bu)償(chang)(chang)(chang)元(yuan)件。利用(yong)(yong)(yong)其(qi)工(gong)(gong)作主(zhu)體波(bo)(bo)紋(wen)管(guan)(guan)(guan)(guan)的(de)有效(xiao)伸(shen)縮(suo)變(bian)形，以吸收(shou)管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容器等由(you)熱脹冷(leng)縮(suo)等原因而產生(sheng)的(de)尺寸(cun)變(bian)化(hua)，或(huo)(huo)補(bu)(bu)償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容器等的(de)軸向(xiang)(xiang)、橫向(xiang)(xiang)和(he)角向(xiang)(xiang)位移。也可用(yong)(yong)(yong)于(yu)降噪(zao)減振。在(zai)現代(dai)工(gong)(gong)業中(zhong)用(yong)(yong)(yong)途廣泛。供熱上(shang)，為了防止供熱管(guan)(guan)(guan)(guan)道升溫時(shi)，由(you)于(yu)熱伸(shen)長或(huo)(huo)溫度應(ying)力而引起(qi)管(guan)(guan)(guan)(guan)道變(bian)形或(huo)(huo)破(po)壞，需要在(zai)管(guan)(guan)(guan)(guan)道上(shang)設置補(bu)(bu)償(chang)(chang)(chang)器，以補(bu)(bu)償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)道的(de)熱伸(shen)長，從而減小(xiao)管(guan)(guan)(guan)(guan)壁的(de)應(ying)力和(he)作用(yong)(yong)(yong)在(zai)閥(fa)件或(huo)(huo)支(zhi)架結構(gou)上(shang)的(de)作用(yong)(yong)(yong)力。