補償(chang)(chang)器(qi)習慣上(shang)也叫膨脹節(jie)，或(huo)伸縮(suo)節(jie)。由(you)構成其(qi)工(gong)(gong)(gong)作(zuo)(zuo)主體(ti)的(de)波(bo)紋(wen)管(guan)(guan)(guan)（一(yi)種彈性元件）和端管(guan)(guan)(guan)、支架、法蘭、導管(guan)(guan)(guan)等(deng)附件組成。 屬于一(yi)種補償(chang)(chang)元件。利用(yong)(yong)其(qi)工(gong)(gong)(gong)作(zuo)(zuo)主體(ti)波(bo)紋(wen)管(guan)(guan)(guan)的(de)有效伸縮(suo)變(bian)形，以(yi)吸(xi)收管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器(qi)等(deng)由(you)熱(re)(re)脹冷縮(suo)等(deng)原因(yin)而(er)(er)產生的(de)尺寸變(bian)化，或(huo)補償(chang)(chang)管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器(qi)等(deng)的(de)軸向(xiang)、橫向(xiang)和角(jiao)向(xiang)位移。也可用(yong)(yong)于降噪減振。在現代工(gong)(gong)(gong)業中(zhong)用(yong)(yong)途廣泛(fan)。供熱(re)(re)上(shang)，為了防止供熱(re)(re)管(guan)(guan)(guan)道(dao)升溫(wen)時，由(you)于熱(re)(re)伸長(chang)或(huo)溫(wen)度(du)應力(li)而(er)(er)引起管(guan)(guan)(guan)道(dao)變(bian)形或(huo)破壞(huai)，需(xu)要在管(guan)(guan)(guan)道(dao)上(shang)設(she)置補償(chang)(chang)器(qi)，以(yi)補償(chang)(chang)管(guan)(guan)(guan)道(dao)的(de)熱(re)(re)伸長(chang)，從而(er)(er)減小管(guan)(guan)(guan)壁的(de)應力(li)和作(zuo)(zuo)用(yong)(yong)在閥件或(huo)支架結構上(shang)的(de)作(zuo)(zuo)用(yong)(yong)力(li)。