補(bu)(bu)償器習慣上(shang)也(ye)叫膨脹節，或伸縮節。由(you)構成(cheng)其工作主(zhu)(zhu)體(ti)的波(bo)紋管(guan)(guan)(guan)（一種(zhong)(zhong)彈性元件(jian)）和(he)端管(guan)(guan)(guan)、支架、法蘭、導(dao)(dao)管(guan)(guan)(guan)等(deng)附件(jian)組(zu)成(cheng)。 屬于(yu)(yu)一種(zhong)(zhong)補(bu)(bu)償元件(jian)。利(li)用(yong)(yong)其工作主(zhu)(zhu)體(ti)波(bo)紋管(guan)(guan)(guan)的有效(xiao)伸縮變(bian)形，以(yi)吸(xi)收管(guan)(guan)(guan)線、導(dao)(dao)管(guan)(guan)(guan)、容器等(deng)由(you)熱(re)脹冷縮等(deng)原因而產生(sheng)的尺寸變(bian)化，或補(bu)(bu)償管(guan)(guan)(guan)線、導(dao)(dao)管(guan)(guan)(guan)、容器等(deng)的軸(zhou)向、橫向和(he)角向位(wei)移。也(ye)可用(yong)(yong)于(yu)(yu)降噪減振。在現代工業中用(yong)(yong)途廣泛(fan)。供熱(re)上(shang)，為了防止(zhi)供熱(re)管(guan)(guan)(guan)道(dao)(dao)升溫時，由(you)于(yu)(yu)熱(re)伸長或溫度(du)應(ying)力(li)而引起管(guan)(guan)(guan)道(dao)(dao)變(bian)形或破壞，需要(yao)在管(guan)(guan)(guan)道(dao)(dao)上(shang)設置補(bu)(bu)償器，以(yi)補(bu)(bu)償管(guan)(guan)(guan)道(dao)(dao)的熱(re)伸長，從而減小管(guan)(guan)(guan)壁的應(ying)力(li)和(he)作用(yong)(yong)在閥(fa)件(jian)或支架結構上(shang)的作用(yong)(yong)力(li)。