補償(chang)器習慣(guan)上也(ye)叫膨脹節，或(huo)(huo)伸(shen)縮(suo)節。由構成其(qi)工作主體的波紋管(guan)(guan)(guan)(guan)（一(yi)種彈(dan)性元件）和(he)端管(guan)(guan)(guan)(guan)、支架(jia)、法蘭、導管(guan)(guan)(guan)(guan)等附(fu)件組(zu)成。 屬于(yu)一(yi)種補償(chang)元件。利用(yong)(yong)其(qi)工作主體波紋管(guan)(guan)(guan)(guan)的有效伸(shen)縮(suo)變形(xing)，以(yi)吸收管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容(rong)(rong)器等由熱脹冷縮(suo)等原因(yin)而(er)產生的尺寸變化，或(huo)(huo)補償(chang)管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容(rong)(rong)器等的軸向(xiang)(xiang)、橫向(xiang)(xiang)和(he)角(jiao)向(xiang)(xiang)位移。也(ye)可用(yong)(yong)于(yu)降噪減(jian)振。在(zai)現代工業中用(yong)(yong)途廣泛。供熱上，為(wei)了防止供熱管(guan)(guan)(guan)(guan)道升溫(wen)時，由于(yu)熱伸(shen)長(chang)或(huo)(huo)溫(wen)度應力(li)而(er)引起管(guan)(guan)(guan)(guan)道變形(xing)或(huo)(huo)破壞，需要在(zai)管(guan)(guan)(guan)(guan)道上設置補償(chang)器，以(yi)補償(chang)管(guan)(guan)(guan)(guan)道的熱伸(shen)長(chang)，從而(er)減(jian)小(xiao)管(guan)(guan)(guan)(guan)壁(bi)的應力(li)和(he)作用(yong)(yong)在(zai)閥件或(huo)(huo)支架(jia)結構上的作用(yong)(yong)力(li)。