補(bu)償(chang)器(qi)習慣(guan)上也叫膨脹節，或伸(shen)縮(suo)節。由(you)構(gou)成其(qi)工(gong)作(zuo)(zuo)主體的(de)(de)波紋管(guan)(guan)(guan)(guan)(guan)（一種彈性元件(jian)）和(he)端管(guan)(guan)(guan)(guan)(guan)、支架、法蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)等附件(jian)組成。 屬于一種補(bu)償(chang)元件(jian)。利用其(qi)工(gong)作(zuo)(zuo)主體波紋管(guan)(guan)(guan)(guan)(guan)的(de)(de)有效伸(shen)縮(suo)變(bian)形，以吸收管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)等由(you)熱(re)脹冷縮(suo)等原因而(er)產(chan)生的(de)(de)尺寸(cun)變(bian)化，或補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)等的(de)(de)軸向(xiang)、橫向(xiang)和(he)角向(xiang)位(wei)移。也可用于降噪減(jian)振。在(zai)現代工(gong)業中(zhong)用途廣泛(fan)。供(gong)熱(re)上，為了防止供(gong)熱(re)管(guan)(guan)(guan)(guan)(guan)道升溫時，由(you)于熱(re)伸(shen)長或溫度應力而(er)引起(qi)管(guan)(guan)(guan)(guan)(guan)道變(bian)形或破壞，需要在(zai)管(guan)(guan)(guan)(guan)(guan)道上設置補(bu)償(chang)器(qi)，以補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)道的(de)(de)熱(re)伸(shen)長，從而(er)減(jian)小管(guan)(guan)(guan)(guan)(guan)壁的(de)(de)應力和(he)作(zuo)(zuo)用在(zai)閥件(jian)或支架結構(gou)上的(de)(de)作(zuo)(zuo)用力。