補償(chang)器(qi)(qi)(qi)(qi)習慣上也(ye)叫膨(peng)脹節，或(huo)伸(shen)縮(suo)(suo)節。由(you)構成(cheng)其工作主體的波(bo)紋管(guan)(guan)(guan)（一(yi)種(zhong)(zhong)彈性(xing)元件(jian)）和(he)端管(guan)(guan)(guan)、支架、法蘭(lan)、導(dao)管(guan)(guan)(guan)等附(fu)件(jian)組成(cheng)。 屬于一(yi)種(zhong)(zhong)補償(chang)元件(jian)。利(li)用(yong)其工作主體波(bo)紋管(guan)(guan)(guan)的有效伸(shen)縮(suo)(suo)變形，以吸收管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)(rong)器(qi)(qi)(qi)(qi)等由(you)熱(re)(re)(re)脹冷縮(suo)(suo)等原因而產生(sheng)的尺寸變化，或(huo)補償(chang)管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)(rong)器(qi)(qi)(qi)(qi)等的軸向、橫向和(he)角向位移。也(ye)可用(yong)于降噪減振。在現(xian)代工業(ye)中(zhong)用(yong)途廣泛。供熱(re)(re)(re)上，為(wei)了(le)防止(zhi)供熱(re)(re)(re)管(guan)(guan)(guan)道(dao)升(sheng)溫時，由(you)于熱(re)(re)(re)伸(shen)長或(huo)溫度(du)應力(li)而引起管(guan)(guan)(guan)道(dao)變形或(huo)破壞，需(xu)要在管(guan)(guan)(guan)道(dao)上設置補償(chang)器(qi)(qi)(qi)(qi)，以補償(chang)管(guan)(guan)(guan)道(dao)的熱(re)(re)(re)伸(shen)長，從而減小(xiao)管(guan)(guan)(guan)壁的應力(li)和(he)作用(yong)在閥件(jian)或(huo)支架結構上的作用(yong)力(li)。