補(bu)償(chang)器(qi)習(xi)慣上(shang)也叫(jiao)膨(peng)脹節，或(huo)伸縮節。由構(gou)成其工作主體的(de)(de)(de)波(bo)紋管(guan)(guan)(guan)(guan)（一種彈性元件）和端管(guan)(guan)(guan)(guan)、支(zhi)架、法(fa)蘭、導管(guan)(guan)(guan)(guan)等(deng)(deng)附件組成。 屬于一種補(bu)償(chang)元件。利用(yong)(yong)其工作主體波(bo)紋管(guan)(guan)(guan)(guan)的(de)(de)(de)有效伸縮變(bian)形，以吸(xi)收管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等(deng)(deng)由熱(re)脹冷(leng)縮等(deng)(deng)原(yuan)因而(er)(er)產生的(de)(de)(de)尺寸(cun)變(bian)化，或(huo)補(bu)償(chang)管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等(deng)(deng)的(de)(de)(de)軸向(xiang)、橫向(xiang)和角(jiao)向(xiang)位移。也可用(yong)(yong)于降噪減(jian)振(zhen)。在(zai)現代(dai)工業中用(yong)(yong)途廣泛。供熱(re)上(shang)，為了(le)防止(zhi)供熱(re)管(guan)(guan)(guan)(guan)道(dao)(dao)升溫時，由于熱(re)伸長或(huo)溫度(du)應(ying)力而(er)(er)引起(qi)管(guan)(guan)(guan)(guan)道(dao)(dao)變(bian)形或(huo)破(po)壞，需要在(zai)管(guan)(guan)(guan)(guan)道(dao)(dao)上(shang)設置補(bu)償(chang)器(qi)，以補(bu)償(chang)管(guan)(guan)(guan)(guan)道(dao)(dao)的(de)(de)(de)熱(re)伸長，從而(er)(er)減(jian)小管(guan)(guan)(guan)(guan)壁的(de)(de)(de)應(ying)力和作用(yong)(yong)在(zai)閥(fa)件或(huo)支(zhi)架結構(gou)上(shang)的(de)(de)(de)作用(yong)(yong)力。