補(bu)償(chang)器(qi)(qi)習慣上(shang)也(ye)叫膨脹(zhang)節，或(huo)伸縮節。由構成(cheng)其工(gong)作主體(ti)的(de)波紋管(guan)(guan)(guan)（一種(zhong)彈性元件(jian)）和端管(guan)(guan)(guan)、支(zhi)架、法蘭(lan)、導(dao)管(guan)(guan)(guan)等附件(jian)組成(cheng)。 屬于(yu)一種(zhong)補(bu)償(chang)元件(jian)。利用(yong)(yong)其工(gong)作主體(ti)波紋管(guan)(guan)(guan)的(de)有(you)效伸縮變形，以吸收管(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)、容(rong)器(qi)(qi)等由熱脹(zhang)冷縮等原(yuan)因而產(chan)生的(de)尺寸(cun)變化，或(huo)補(bu)償(chang)管(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)、容(rong)器(qi)(qi)等的(de)軸向、橫向和角向位移。也(ye)可用(yong)(yong)于(yu)降噪減振。在(zai)現代工(gong)業中(zhong)用(yong)(yong)途廣(guang)泛。供熱上(shang)，為(wei)了(le)防止供熱管(guan)(guan)(guan)道升溫時，由于(yu)熱伸長(chang)或(huo)溫度應力(li)(li)而引起管(guan)(guan)(guan)道變形或(huo)破壞，需(xu)要在(zai)管(guan)(guan)(guan)道上(shang)設置補(bu)償(chang)器(qi)(qi)，以補(bu)償(chang)管(guan)(guan)(guan)道的(de)熱伸長(chang)，從(cong)而減小管(guan)(guan)(guan)壁的(de)應力(li)(li)和作用(yong)(yong)在(zai)閥件(jian)或(huo)支(zhi)架結構上(shang)的(de)作用(yong)(yong)力(li)(li)。