補(bu)償(chang)(chang)器(qi)習慣上(shang)也叫膨脹(zhang)節，或(huo)(huo)伸縮節。由構成其工(gong)作(zuo)(zuo)主體(ti)的(de)波(bo)紋(wen)管(guan)(guan)（一(yi)種(zhong)彈性元(yuan)件(jian)(jian)(jian)）和端管(guan)(guan)、支(zhi)架、法蘭(lan)、導管(guan)(guan)等(deng)附(fu)件(jian)(jian)(jian)組成。 屬于一(yi)種(zhong)補(bu)償(chang)(chang)元(yuan)件(jian)(jian)(jian)。利用(yong)(yong)其工(gong)作(zuo)(zuo)主體(ti)波(bo)紋(wen)管(guan)(guan)的(de)有效伸縮變(bian)形，以吸收管(guan)(guan)線、導管(guan)(guan)、容(rong)器(qi)等(deng)由熱(re)脹(zhang)冷縮等(deng)原(yuan)因而(er)產生的(de)尺寸變(bian)化，或(huo)(huo)補(bu)償(chang)(chang)管(guan)(guan)線、導管(guan)(guan)、容(rong)器(qi)等(deng)的(de)軸(zhou)向、橫向和角向位移(yi)。也可用(yong)(yong)于降噪減(jian)振(zhen)。在(zai)現代工(gong)業中用(yong)(yong)途廣(guang)泛。供熱(re)上(shang)，為(wei)了(le)防止供熱(re)管(guan)(guan)道升溫時，由于熱(re)伸長或(huo)(huo)溫度應力而(er)引起管(guan)(guan)道變(bian)形或(huo)(huo)破壞(huai)，需要在(zai)管(guan)(guan)道上(shang)設置補(bu)償(chang)(chang)器(qi)，以補(bu)償(chang)(chang)管(guan)(guan)道的(de)熱(re)伸長，從而(er)減(jian)小管(guan)(guan)壁(bi)的(de)應力和作(zuo)(zuo)用(yong)(yong)在(zai)閥(fa)件(jian)(jian)(jian)或(huo)(huo)支(zhi)架結(jie)構上(shang)的(de)作(zuo)(zuo)用(yong)(yong)力。