補(bu)(bu)償(chang)器(qi)(qi)習慣上(shang)(shang)(shang)也(ye)叫膨(peng)脹(zhang)節，或(huo)伸(shen)縮節。由構成(cheng)(cheng)其工(gong)(gong)作(zuo)(zuo)主體(ti)(ti)的(de)(de)波紋(wen)(wen)管(guan)(guan)（一種彈性元件(jian)(jian)）和(he)(he)端管(guan)(guan)、支架、法蘭、導(dao)(dao)(dao)管(guan)(guan)等附件(jian)(jian)組成(cheng)(cheng)。 屬于一種補(bu)(bu)償(chang)元件(jian)(jian)。利用(yong)(yong)其工(gong)(gong)作(zuo)(zuo)主體(ti)(ti)波紋(wen)(wen)管(guan)(guan)的(de)(de)有效伸(shen)縮變(bian)形(xing)，以(yi)吸收管(guan)(guan)線、導(dao)(dao)(dao)管(guan)(guan)、容(rong)器(qi)(qi)等由熱(re)脹(zhang)冷縮等原因而(er)(er)產生的(de)(de)尺寸變(bian)化(hua)，或(huo)補(bu)(bu)償(chang)管(guan)(guan)線、導(dao)(dao)(dao)管(guan)(guan)、容(rong)器(qi)(qi)等的(de)(de)軸向(xiang)、橫向(xiang)和(he)(he)角向(xiang)位移。也(ye)可(ke)用(yong)(yong)于降噪減(jian)振。在(zai)現(xian)代(dai)工(gong)(gong)業(ye)中用(yong)(yong)途廣(guang)泛。供熱(re)上(shang)(shang)(shang)，為了防(fang)止供熱(re)管(guan)(guan)道(dao)升溫時，由于熱(re)伸(shen)長或(huo)溫度應(ying)力(li)而(er)(er)引起管(guan)(guan)道(dao)變(bian)形(xing)或(huo)破壞，需(xu)要在(zai)管(guan)(guan)道(dao)上(shang)(shang)(shang)設(she)置補(bu)(bu)償(chang)器(qi)(qi)，以(yi)補(bu)(bu)償(chang)管(guan)(guan)道(dao)的(de)(de)熱(re)伸(shen)長，從而(er)(er)減(jian)小管(guan)(guan)壁的(de)(de)應(ying)力(li)和(he)(he)作(zuo)(zuo)用(yong)(yong)在(zai)閥件(jian)(jian)或(huo)支架結構上(shang)(shang)(shang)的(de)(de)作(zuo)(zuo)用(yong)(yong)力(li)。