補(bu)(bu)(bu)償(chang)器(qi)(qi)習慣(guan)上(shang)也(ye)叫膨脹節，或(huo)(huo)伸縮節。由構成其工(gong)(gong)作(zuo)主體的(de)波紋管(guan)(guan)(guan)(guan)（一種(zhong)彈(dan)性元(yuan)件(jian)）和端(duan)管(guan)(guan)(guan)(guan)、支(zhi)架(jia)(jia)、法蘭、導(dao)管(guan)(guan)(guan)(guan)等(deng)附件(jian)組(zu)成。 屬于一種(zhong)補(bu)(bu)(bu)償(chang)元(yuan)件(jian)。利(li)用(yong)其工(gong)(gong)作(zuo)主體波紋管(guan)(guan)(guan)(guan)的(de)有效伸縮變形，以吸收管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等(deng)由熱脹冷縮等(deng)原因而產生的(de)尺寸變化，或(huo)(huo)補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等(deng)的(de)軸向、橫向和角(jiao)向位移。也(ye)可(ke)用(yong)于降噪減(jian)振(zhen)。在現代工(gong)(gong)業中用(yong)途廣泛。供熱上(shang)，為(wei)了防止供熱管(guan)(guan)(guan)(guan)道升(sheng)溫時，由于熱伸長或(huo)(huo)溫度應力(li)而引(yin)起(qi)管(guan)(guan)(guan)(guan)道變形或(huo)(huo)破壞，需(xu)要在管(guan)(guan)(guan)(guan)道上(shang)設置(zhi)補(bu)(bu)(bu)償(chang)器(qi)(qi)，以補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)道的(de)熱伸長，從而減(jian)小管(guan)(guan)(guan)(guan)壁的(de)應力(li)和作(zuo)用(yong)在閥件(jian)或(huo)(huo)支(zhi)架(jia)(jia)結構上(shang)的(de)作(zuo)用(yong)力(li)。