補(bu)償(chang)(chang)器習慣上(shang)(shang)也叫膨脹節，或(huo)(huo)(huo)伸縮節。由構成(cheng)(cheng)其(qi)工(gong)(gong)作(zuo)主(zhu)體的(de)(de)波紋(wen)管(guan)(guan)（一種彈性元(yuan)件(jian)(jian)）和(he)(he)端管(guan)(guan)、支(zhi)(zhi)架、法蘭、導管(guan)(guan)等附件(jian)(jian)組成(cheng)(cheng)。 屬于一種補(bu)償(chang)(chang)元(yuan)件(jian)(jian)。利用(yong)(yong)其(qi)工(gong)(gong)作(zuo)主(zhu)體波紋(wen)管(guan)(guan)的(de)(de)有(you)效伸縮變(bian)(bian)形(xing)(xing)，以(yi)吸收管(guan)(guan)線、導管(guan)(guan)、容器等由熱(re)(re)脹冷縮等原因而(er)產(chan)生的(de)(de)尺寸變(bian)(bian)化(hua)，或(huo)(huo)(huo)補(bu)償(chang)(chang)管(guan)(guan)線、導管(guan)(guan)、容器等的(de)(de)軸向(xiang)、橫向(xiang)和(he)(he)角向(xiang)位移。也可用(yong)(yong)于降噪減振。在(zai)現代工(gong)(gong)業中用(yong)(yong)途廣(guang)泛。供(gong)(gong)熱(re)(re)上(shang)(shang)，為了防止(zhi)供(gong)(gong)熱(re)(re)管(guan)(guan)道升溫(wen)時，由于熱(re)(re)伸長或(huo)(huo)(huo)溫(wen)度應力(li)(li)而(er)引(yin)起(qi)管(guan)(guan)道變(bian)(bian)形(xing)(xing)或(huo)(huo)(huo)破壞，需要在(zai)管(guan)(guan)道上(shang)(shang)設置(zhi)補(bu)償(chang)(chang)器，以(yi)補(bu)償(chang)(chang)管(guan)(guan)道的(de)(de)熱(re)(re)伸長，從而(er)減小(xiao)管(guan)(guan)壁的(de)(de)應力(li)(li)和(he)(he)作(zuo)用(yong)(yong)在(zai)閥件(jian)(jian)或(huo)(huo)(huo)支(zhi)(zhi)架結構上(shang)(shang)的(de)(de)作(zuo)用(yong)(yong)力(li)(li)。