補(bu)(bu)償器(qi)習(xi)慣上也(ye)叫膨(peng)脹(zhang)節，或(huo)伸縮節。由構(gou)成(cheng)(cheng)其(qi)工作(zuo)主(zhu)體的波紋管(guan)(guan)(guan)(guan)(guan)（一(yi)種(zhong)彈(dan)性元件(jian)）和端管(guan)(guan)(guan)(guan)(guan)、支(zhi)(zhi)架、法(fa)蘭、導管(guan)(guan)(guan)(guan)(guan)等附(fu)件(jian)組成(cheng)(cheng)。 屬于一(yi)種(zhong)補(bu)(bu)償元件(jian)。利(li)用(yong)其(qi)工作(zuo)主(zhu)體波紋管(guan)(guan)(guan)(guan)(guan)的有效伸縮變形，以吸(xi)收管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等由熱(re)(re)脹(zhang)冷縮等原因而(er)產生(sheng)的尺(chi)寸變化，或(huo)補(bu)(bu)償管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等的軸向、橫向和角向位移(yi)。也(ye)可用(yong)于降噪減振。在現代工業中用(yong)途廣泛。供熱(re)(re)上，為了(le)防(fang)止(zhi)供熱(re)(re)管(guan)(guan)(guan)(guan)(guan)道(dao)升溫(wen)時(shi)，由于熱(re)(re)伸長或(huo)溫(wen)度應(ying)(ying)力而(er)引起管(guan)(guan)(guan)(guan)(guan)道(dao)變形或(huo)破壞，需(xu)要(yao)在管(guan)(guan)(guan)(guan)(guan)道(dao)上設置(zhi)補(bu)(bu)償器(qi)，以補(bu)(bu)償管(guan)(guan)(guan)(guan)(guan)道(dao)的熱(re)(re)伸長，從而(er)減小管(guan)(guan)(guan)(guan)(guan)壁的應(ying)(ying)力和作(zuo)用(yong)在閥(fa)件(jian)或(huo)支(zhi)(zhi)架結構(gou)上的作(zuo)用(yong)力。