補(bu)(bu)(bu)償(chang)器(qi)(qi)習慣上也叫(jiao)膨(peng)脹(zhang)(zhang)節，或伸(shen)(shen)縮節。由(you)(you)構(gou)成其(qi)工作主(zhu)體(ti)的(de)(de)波紋(wen)(wen)管(guan)(guan)(guan)(guan)（一(yi)種(zhong)彈性(xing)元件(jian)）和(he)端(duan)管(guan)(guan)(guan)(guan)、支架、法蘭(lan)、導管(guan)(guan)(guan)(guan)等(deng)附件(jian)組成。 屬于一(yi)種(zhong)補(bu)(bu)(bu)償(chang)元件(jian)。利(li)用(yong)(yong)(yong)其(qi)工作主(zhu)體(ti)波紋(wen)(wen)管(guan)(guan)(guan)(guan)的(de)(de)有效(xiao)伸(shen)(shen)縮變形，以吸收管(guan)(guan)(guan)(guan)線(xian)(xian)、導管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由(you)(you)熱(re)(re)脹(zhang)(zhang)冷(leng)縮等(deng)原因而(er)產生的(de)(de)尺(chi)寸變化(hua)，或補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)線(xian)(xian)、導管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的(de)(de)軸(zhou)向(xiang)(xiang)、橫向(xiang)(xiang)和(he)角向(xiang)(xiang)位移。也可用(yong)(yong)(yong)于降(jiang)噪減振。在(zai)現代工業中用(yong)(yong)(yong)途廣泛。供熱(re)(re)上，為了防止(zhi)供熱(re)(re)管(guan)(guan)(guan)(guan)道升溫(wen)時(shi)，由(you)(you)于熱(re)(re)伸(shen)(shen)長(chang)或溫(wen)度應力(li)而(er)引起管(guan)(guan)(guan)(guan)道變形或破壞，需(xu)要在(zai)管(guan)(guan)(guan)(guan)道上設置(zhi)補(bu)(bu)(bu)償(chang)器(qi)(qi)，以補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)道的(de)(de)熱(re)(re)伸(shen)(shen)長(chang)，從而(er)減小管(guan)(guan)(guan)(guan)壁(bi)的(de)(de)應力(li)和(he)作用(yong)(yong)(yong)在(zai)閥件(jian)或支架結(jie)構(gou)上的(de)(de)作用(yong)(yong)(yong)力(li)。