補償(chang)器(qi)習慣上也(ye)叫膨脹節，或(huo)伸(shen)縮(suo)節。由(you)構成其工(gong)(gong)作主(zhu)體(ti)的(de)(de)(de)波(bo)紋管(guan)(guan)(guan)(guan)（一(yi)種(zhong)彈(dan)性(xing)元件(jian)）和端管(guan)(guan)(guan)(guan)、支架、法(fa)蘭、導管(guan)(guan)(guan)(guan)等附件(jian)組成。 屬于一(yi)種(zhong)補償(chang)元件(jian)。利用其工(gong)(gong)作主(zhu)體(ti)波(bo)紋管(guan)(guan)(guan)(guan)的(de)(de)(de)有效(xiao)伸(shen)縮(suo)變(bian)(bian)形，以(yi)吸收管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等由(you)熱(re)(re)脹冷(leng)縮(suo)等原(yuan)因(yin)而(er)產生的(de)(de)(de)尺寸變(bian)(bian)化，或(huo)補償(chang)管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等的(de)(de)(de)軸向(xiang)(xiang)、橫向(xiang)(xiang)和角向(xiang)(xiang)位移。也(ye)可用于降噪減(jian)振。在現代工(gong)(gong)業中用途(tu)廣泛。供熱(re)(re)上，為了(le)防(fang)止供熱(re)(re)管(guan)(guan)(guan)(guan)道(dao)升溫時(shi)，由(you)于熱(re)(re)伸(shen)長或(huo)溫度應(ying)力而(er)引起管(guan)(guan)(guan)(guan)道(dao)變(bian)(bian)形或(huo)破壞，需要在管(guan)(guan)(guan)(guan)道(dao)上設置補償(chang)器(qi)，以(yi)補償(chang)管(guan)(guan)(guan)(guan)道(dao)的(de)(de)(de)熱(re)(re)伸(shen)長，從而(er)減(jian)小管(guan)(guan)(guan)(guan)壁的(de)(de)(de)應(ying)力和作用在閥(fa)件(jian)或(huo)支架結構上的(de)(de)(de)作用力。