補(bu)償(chang)器(qi)習慣(guan)上也叫(jiao)膨脹節(jie)，或(huo)(huo)伸(shen)(shen)縮(suo)節(jie)。由構(gou)成其工作(zuo)主(zhu)體(ti)的波(bo)紋管(guan)(guan)(guan)(guan)（一種彈(dan)性元件(jian)）和(he)端管(guan)(guan)(guan)(guan)、支架(jia)、法蘭、導管(guan)(guan)(guan)(guan)等附件(jian)組成。 屬于一種補(bu)償(chang)元件(jian)。利用(yong)(yong)其工作(zuo)主(zhu)體(ti)波(bo)紋管(guan)(guan)(guan)(guan)的有效伸(shen)(shen)縮(suo)變(bian)形，以吸收管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等由熱(re)脹冷縮(suo)等原因(yin)而產生(sheng)的尺寸變(bian)化，或(huo)(huo)補(bu)償(chang)管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等的軸(zhou)向(xiang)(xiang)、橫向(xiang)(xiang)和(he)角向(xiang)(xiang)位(wei)移。也可用(yong)(yong)于降(jiang)噪減(jian)振。在現代工業中用(yong)(yong)途廣泛(fan)。供熱(re)上，為了(le)防止供熱(re)管(guan)(guan)(guan)(guan)道(dao)升溫時，由于熱(re)伸(shen)(shen)長或(huo)(huo)溫度(du)應(ying)力(li)而引(yin)起管(guan)(guan)(guan)(guan)道(dao)變(bian)形或(huo)(huo)破(po)壞，需(xu)要(yao)在管(guan)(guan)(guan)(guan)道(dao)上設(she)置補(bu)償(chang)器(qi)，以補(bu)償(chang)管(guan)(guan)(guan)(guan)道(dao)的熱(re)伸(shen)(shen)長，從而減(jian)小管(guan)(guan)(guan)(guan)壁的應(ying)力(li)和(he)作(zuo)用(yong)(yong)在閥件(jian)或(huo)(huo)支架(jia)結構(gou)上的作(zuo)用(yong)(yong)力(li)。