補償(chang)器(qi)習慣上(shang)也叫膨(peng)脹節，或(huo)伸(shen)(shen)縮(suo)節。由(you)構成(cheng)其(qi)工(gong)作(zuo)主體的(de)(de)波(bo)紋(wen)管(guan)(guan)(guan)(guan)（一種彈性元件(jian)）和(he)(he)(he)端管(guan)(guan)(guan)(guan)、支(zhi)架(jia)、法蘭(lan)、導管(guan)(guan)(guan)(guan)等附件(jian)組成(cheng)。 屬于一種補償(chang)元件(jian)。利用(yong)(yong)其(qi)工(gong)作(zuo)主體波(bo)紋(wen)管(guan)(guan)(guan)(guan)的(de)(de)有效伸(shen)(shen)縮(suo)變(bian)形，以吸收管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容器(qi)等由(you)熱脹冷縮(suo)等原因而(er)產生(sheng)的(de)(de)尺寸變(bian)化，或(huo)補償(chang)管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容器(qi)等的(de)(de)軸向、橫向和(he)(he)(he)角向位移。也可(ke)用(yong)(yong)于降(jiang)噪減振。在(zai)現代工(gong)業(ye)中(zhong)用(yong)(yong)途廣泛。供熱上(shang)，為了防止供熱管(guan)(guan)(guan)(guan)道(dao)升溫時，由(you)于熱伸(shen)(shen)長或(huo)溫度應力(li)而(er)引起(qi)管(guan)(guan)(guan)(guan)道(dao)變(bian)形或(huo)破壞，需要在(zai)管(guan)(guan)(guan)(guan)道(dao)上(shang)設置補償(chang)器(qi)，以補償(chang)管(guan)(guan)(guan)(guan)道(dao)的(de)(de)熱伸(shen)(shen)長，從而(er)減小管(guan)(guan)(guan)(guan)壁的(de)(de)應力(li)和(he)(he)(he)作(zuo)用(yong)(yong)在(zai)閥件(jian)或(huo)支(zhi)架(jia)結構上(shang)的(de)(de)作(zuo)用(yong)(yong)力(li)。