補償器(qi)習(xi)慣上也叫膨脹(zhang)(zhang)節，或伸縮節。由(you)(you)構成其工(gong)作(zuo)主(zhu)體的(de)波紋管(guan)(guan)(guan)(guan)(guan)（一種(zhong)彈(dan)性(xing)元件(jian)）和(he)端(duan)管(guan)(guan)(guan)(guan)(guan)、支(zhi)架(jia)、法蘭、導管(guan)(guan)(guan)(guan)(guan)等(deng)附件(jian)組(zu)成。 屬于一種(zhong)補償元件(jian)。利用(yong)其工(gong)作(zuo)主(zhu)體波紋管(guan)(guan)(guan)(guan)(guan)的(de)有效伸縮變形，以吸收管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)由(you)(you)熱(re)脹(zhang)(zhang)冷縮等(deng)原因(yin)而產生的(de)尺寸變化，或補償管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)的(de)軸向、橫向和(he)角向位移(yi)。也可用(yong)于降噪減振。在(zai)現代(dai)工(gong)業中用(yong)途廣泛。供熱(re)上，為了防止供熱(re)管(guan)(guan)(guan)(guan)(guan)道(dao)升溫(wen)時，由(you)(you)于熱(re)伸長或溫(wen)度(du)應力(li)而引起管(guan)(guan)(guan)(guan)(guan)道(dao)變形或破(po)壞(huai)，需要(yao)在(zai)管(guan)(guan)(guan)(guan)(guan)道(dao)上設置補償器(qi)，以補償管(guan)(guan)(guan)(guan)(guan)道(dao)的(de)熱(re)伸長，從而減小(xiao)管(guan)(guan)(guan)(guan)(guan)壁的(de)應力(li)和(he)作(zuo)用(yong)在(zai)閥(fa)件(jian)或支(zhi)架(jia)結構上的(de)作(zuo)用(yong)力(li)。