補(bu)(bu)償(chang)(chang)(chang)器(qi)習(xi)慣上(shang)(shang)也叫膨脹(zhang)節，或伸(shen)縮節。由(you)(you)構成其工(gong)作(zuo)(zuo)主(zhu)(zhu)體的波(bo)紋管(guan)(guan)(guan)(guan)（一種(zhong)彈性元件(jian)(jian)）和(he)(he)端管(guan)(guan)(guan)(guan)、支架(jia)、法蘭、導管(guan)(guan)(guan)(guan)等附件(jian)(jian)組成。 屬于一種(zhong)補(bu)(bu)償(chang)(chang)(chang)元件(jian)(jian)。利用(yong)其工(gong)作(zuo)(zuo)主(zhu)(zhu)體波(bo)紋管(guan)(guan)(guan)(guan)的有效伸(shen)縮變形(xing)，以(yi)吸(xi)收(shou)管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器(qi)等由(you)(you)熱(re)(re)脹(zhang)冷縮等原(yuan)因而(er)產生(sheng)的尺寸(cun)變化，或補(bu)(bu)償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器(qi)等的軸向、橫(heng)向和(he)(he)角向位移(yi)。也可用(yong)于降噪減(jian)振。在現(xian)代工(gong)業中(zhong)用(yong)途廣泛(fan)。供(gong)(gong)熱(re)(re)上(shang)(shang)，為了防止供(gong)(gong)熱(re)(re)管(guan)(guan)(guan)(guan)道升溫(wen)(wen)時，由(you)(you)于熱(re)(re)伸(shen)長或溫(wen)(wen)度應力而(er)引(yin)起管(guan)(guan)(guan)(guan)道變形(xing)或破壞，需要在管(guan)(guan)(guan)(guan)道上(shang)(shang)設置補(bu)(bu)償(chang)(chang)(chang)器(qi)，以(yi)補(bu)(bu)償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)道的熱(re)(re)伸(shen)長，從而(er)減(jian)小管(guan)(guan)(guan)(guan)壁的應力和(he)(he)作(zuo)(zuo)用(yong)在閥件(jian)(jian)或支架(jia)結(jie)構上(shang)(shang)的作(zuo)(zuo)用(yong)力。