補償(chang)(chang)器(qi)習慣上(shang)也叫膨脹節，或伸縮節。由(you)構(gou)成其(qi)工(gong)作主體的(de)(de)(de)波紋管(guan)(guan)(guan)（一種彈(dan)性元件(jian)）和端管(guan)(guan)(guan)、支(zhi)架、法蘭、導管(guan)(guan)(guan)等附(fu)件(jian)組成。 屬(shu)于一種補償(chang)(chang)元件(jian)。利(li)用(yong)(yong)其(qi)工(gong)作主體波紋管(guan)(guan)(guan)的(de)(de)(de)有效伸縮變(bian)形，以吸收(shou)管(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)、容器(qi)等由(you)熱(re)(re)(re)脹冷縮等原因而產(chan)生(sheng)的(de)(de)(de)尺(chi)寸(cun)變(bian)化，或補償(chang)(chang)管(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)、容器(qi)等的(de)(de)(de)軸向、橫向和角向位移(yi)。也可用(yong)(yong)于降噪減振。在現(xian)代工(gong)業中(zhong)用(yong)(yong)途廣泛。供(gong)(gong)熱(re)(re)(re)上(shang)，為了防止供(gong)(gong)熱(re)(re)(re)管(guan)(guan)(guan)道升溫(wen)時(shi)，由(you)于熱(re)(re)(re)伸長(chang)或溫(wen)度應力而引起管(guan)(guan)(guan)道變(bian)形或破壞，需要在管(guan)(guan)(guan)道上(shang)設置補償(chang)(chang)器(qi)，以補償(chang)(chang)管(guan)(guan)(guan)道的(de)(de)(de)熱(re)(re)(re)伸長(chang)，從而減小管(guan)(guan)(guan)壁(bi)的(de)(de)(de)應力和作用(yong)(yong)在閥件(jian)或支(zhi)架結(jie)構(gou)上(shang)的(de)(de)(de)作用(yong)(yong)力。