補(bu)償器(qi)(qi)習慣上也(ye)叫膨脹節，或伸(shen)縮節。由(you)構(gou)成其工(gong)作(zuo)(zuo)主體(ti)(ti)的波紋管(guan)(guan)(guan)(guan)（一(yi)種(zhong)彈性(xing)元件(jian)(jian)）和端管(guan)(guan)(guan)(guan)、支架、法蘭、導管(guan)(guan)(guan)(guan)等(deng)附件(jian)(jian)組成。 屬于(yu)(yu)一(yi)種(zhong)補(bu)償元件(jian)(jian)。利用(yong)(yong)(yong)其工(gong)作(zuo)(zuo)主體(ti)(ti)波紋管(guan)(guan)(guan)(guan)的有效伸(shen)縮變(bian)(bian)形(xing)，以吸(xi)收管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由(you)熱(re)脹冷縮等(deng)原因而產生(sheng)的尺寸(cun)變(bian)(bian)化，或補(bu)償管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的軸向(xiang)、橫向(xiang)和角向(xiang)位移(yi)。也(ye)可用(yong)(yong)(yong)于(yu)(yu)降噪減振。在(zai)現代工(gong)業(ye)中用(yong)(yong)(yong)途(tu)廣(guang)泛。供(gong)熱(re)上，為了防止供(gong)熱(re)管(guan)(guan)(guan)(guan)道(dao)升溫時，由(you)于(yu)(yu)熱(re)伸(shen)長(chang)或溫度應力(li)而引起管(guan)(guan)(guan)(guan)道(dao)變(bian)(bian)形(xing)或破壞，需要在(zai)管(guan)(guan)(guan)(guan)道(dao)上設(she)置補(bu)償器(qi)(qi)，以補(bu)償管(guan)(guan)(guan)(guan)道(dao)的熱(re)伸(shen)長(chang)，從而減小管(guan)(guan)(guan)(guan)壁的應力(li)和作(zuo)(zuo)用(yong)(yong)(yong)在(zai)閥件(jian)(jian)或支架結構(gou)上的作(zuo)(zuo)用(yong)(yong)(yong)力(li)。