補(bu)(bu)(bu)償(chang)器習慣上(shang)也叫膨脹(zhang)(zhang)節，或伸(shen)(shen)縮節。由構(gou)成其工作(zuo)主(zhu)(zhu)體的波紋管(guan)(guan)(guan)（一(yi)種(zhong)彈性元件(jian)）和端管(guan)(guan)(guan)、支架、法蘭、導(dao)管(guan)(guan)(guan)等附(fu)件(jian)組成。 屬于一(yi)種(zhong)補(bu)(bu)(bu)償(chang)元件(jian)。利用(yong)(yong)其工作(zuo)主(zhu)(zhu)體波紋管(guan)(guan)(guan)的有(you)效伸(shen)(shen)縮變形，以吸收(shou)管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容器等由熱脹(zhang)(zhang)冷(leng)縮等原因而產生的尺寸變化，或補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容器等的軸向、橫向和角向位(wei)移(yi)。也可用(yong)(yong)于降噪(zao)減振。在(zai)現(xian)代工業中用(yong)(yong)途廣泛。供(gong)熱上(shang)，為了防(fang)止供(gong)熱管(guan)(guan)(guan)道升溫時，由于熱伸(shen)(shen)長或溫度應力而引起(qi)管(guan)(guan)(guan)道變形或破壞(huai)，需要在(zai)管(guan)(guan)(guan)道上(shang)設置補(bu)(bu)(bu)償(chang)器，以補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)道的熱伸(shen)(shen)長，從而減小(xiao)管(guan)(guan)(guan)壁的應力和作(zuo)用(yong)(yong)在(zai)閥件(jian)或支架結構(gou)上(shang)的作(zuo)用(yong)(yong)力。