補(bu)償器(qi)習慣上(shang)也叫膨脹(zhang)節，或伸縮節。由(you)構成其工(gong)作主(zhu)體的(de)(de)波紋(wen)管(guan)(guan)(guan)(guan)(guan)（一種彈(dan)性元(yuan)件）和(he)端管(guan)(guan)(guan)(guan)(guan)、支架(jia)、法蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)等附件組成。 屬于(yu)一種補(bu)償元(yuan)件。利用(yong)(yong)其工(gong)作主(zhu)體波紋(wen)管(guan)(guan)(guan)(guan)(guan)的(de)(de)有效伸縮變(bian)形，以(yi)吸(xi)收管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)等由(you)熱(re)(re)脹(zhang)冷縮等原(yuan)因而(er)(er)產生的(de)(de)尺寸(cun)變(bian)化，或補(bu)償管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)等的(de)(de)軸向、橫向和(he)角向位移。也可用(yong)(yong)于(yu)降噪(zao)減振。在(zai)(zai)現(xian)代工(gong)業中用(yong)(yong)途廣泛。供熱(re)(re)上(shang)，為了(le)防止供熱(re)(re)管(guan)(guan)(guan)(guan)(guan)道升溫時(shi)，由(you)于(yu)熱(re)(re)伸長(chang)或溫度應力而(er)(er)引起管(guan)(guan)(guan)(guan)(guan)道變(bian)形或破(po)壞，需要(yao)在(zai)(zai)管(guan)(guan)(guan)(guan)(guan)道上(shang)設置補(bu)償器(qi)，以(yi)補(bu)償管(guan)(guan)(guan)(guan)(guan)道的(de)(de)熱(re)(re)伸長(chang)，從(cong)而(er)(er)減小管(guan)(guan)(guan)(guan)(guan)壁的(de)(de)應力和(he)作用(yong)(yong)在(zai)(zai)閥件或支架(jia)結(jie)構上(shang)的(de)(de)作用(yong)(yong)力。