補償(chang)(chang)(chang)器習慣(guan)上也(ye)叫膨脹節，或(huo)伸縮(suo)節。由(you)構成其工作(zuo)(zuo)主(zhu)體的(de)波(bo)(bo)紋管(guan)(guan)(guan)(guan)（一種彈性元件）和端管(guan)(guan)(guan)(guan)、支架、法(fa)蘭、導管(guan)(guan)(guan)(guan)等附件組成。 屬于一種補償(chang)(chang)(chang)元件。利用(yong)(yong)其工作(zuo)(zuo)主(zhu)體波(bo)(bo)紋管(guan)(guan)(guan)(guan)的(de)有(you)效伸縮(suo)變(bian)形，以吸收管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器等由(you)熱(re)脹冷縮(suo)等原(yuan)因而產(chan)生的(de)尺寸變(bian)化(hua)，或(huo)補償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器等的(de)軸向(xiang)、橫向(xiang)和角向(xiang)位移。也(ye)可用(yong)(yong)于降(jiang)噪減振。在現代工業中用(yong)(yong)途廣泛(fan)。供(gong)(gong)熱(re)上，為(wei)了防止供(gong)(gong)熱(re)管(guan)(guan)(guan)(guan)道升溫時(shi)，由(you)于熱(re)伸長(chang)或(huo)溫度應(ying)力(li)而引起(qi)管(guan)(guan)(guan)(guan)道變(bian)形或(huo)破壞，需要(yao)在管(guan)(guan)(guan)(guan)道上設置補償(chang)(chang)(chang)器，以補償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)道的(de)熱(re)伸長(chang)，從(cong)而減小管(guan)(guan)(guan)(guan)壁的(de)應(ying)力(li)和作(zuo)(zuo)用(yong)(yong)在閥件或(huo)支架結構上的(de)作(zuo)(zuo)用(yong)(yong)力(li)。