補(bu)(bu)償器習慣上(shang)也(ye)叫膨脹節，或(huo)伸縮(suo)節。由構成其工(gong)作主體的(de)波紋(wen)管(guan)(guan)(guan)（一種(zhong)彈性元件(jian)）和(he)(he)(he)端(duan)管(guan)(guan)(guan)、支架、法蘭、導管(guan)(guan)(guan)等附件(jian)組成。 屬于(yu)一種(zhong)補(bu)(bu)償元件(jian)。利用(yong)其工(gong)作主體波紋(wen)管(guan)(guan)(guan)的(de)有效伸縮(suo)變(bian)(bian)形，以吸收管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容器等由熱(re)脹冷縮(suo)等原因而(er)產生(sheng)的(de)尺(chi)寸(cun)變(bian)(bian)化(hua)，或(huo)補(bu)(bu)償管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容器等的(de)軸向(xiang)、橫向(xiang)和(he)(he)(he)角向(xiang)位移。也(ye)可用(yong)于(yu)降噪(zao)減振(zhen)。在(zai)現代工(gong)業中用(yong)途廣(guang)泛(fan)。供(gong)熱(re)上(shang)，為了(le)防止供(gong)熱(re)管(guan)(guan)(guan)道升溫(wen)時，由于(yu)熱(re)伸長或(huo)溫(wen)度應力而(er)引起(qi)管(guan)(guan)(guan)道變(bian)(bian)形或(huo)破壞，需要在(zai)管(guan)(guan)(guan)道上(shang)設置補(bu)(bu)償器，以補(bu)(bu)償管(guan)(guan)(guan)道的(de)熱(re)伸長，從而(er)減小管(guan)(guan)(guan)壁(bi)的(de)應力和(he)(he)(he)作用(yong)在(zai)閥件(jian)或(huo)支架結構上(shang)的(de)作用(yong)力。