補償(chang)器(qi)習慣上也叫(jiao)膨脹(zhang)節，或伸縮(suo)節。由構成(cheng)其(qi)(qi)工(gong)作主體(ti)的波紋管(guan)(guan)(guan)（一種(zhong)彈性元件(jian)(jian)）和端(duan)管(guan)(guan)(guan)、支架、法(fa)蘭、導(dao)管(guan)(guan)(guan)等(deng)附件(jian)(jian)組(zu)成(cheng)。 屬于一種(zhong)補償(chang)元件(jian)(jian)。利用其(qi)(qi)工(gong)作主體(ti)波紋管(guan)(guan)(guan)的有效伸縮(suo)變形，以吸收管(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)、容(rong)器(qi)等(deng)由熱(re)脹(zhang)冷縮(suo)等(deng)原因而產生的尺寸(cun)變化(hua)，或補償(chang)管(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)、容(rong)器(qi)等(deng)的軸(zhou)向、橫向和角向位移(yi)。也可用于降噪(zao)減振。在現代(dai)工(gong)業中用途(tu)廣泛。供(gong)熱(re)上，為(wei)了防止(zhi)供(gong)熱(re)管(guan)(guan)(guan)道(dao)升溫時，由于熱(re)伸長(chang)或溫度應(ying)力而引起管(guan)(guan)(guan)道(dao)變形或破壞，需要在管(guan)(guan)(guan)道(dao)上設置補償(chang)器(qi)，以補償(chang)管(guan)(guan)(guan)道(dao)的熱(re)伸長(chang)，從(cong)而減小管(guan)(guan)(guan)壁的應(ying)力和作用在閥件(jian)(jian)或支架結構上的作用力。