補(bu)償器習慣上也叫膨脹節(jie)，或(huo)伸(shen)縮節(jie)。由(you)構成(cheng)其工(gong)作主(zhu)體的波(bo)紋管(guan)(guan)(guan)(guan)（一種(zhong)彈性元件(jian)(jian)）和端(duan)管(guan)(guan)(guan)(guan)、支架、法蘭、導(dao)管(guan)(guan)(guan)(guan)等附件(jian)(jian)組成(cheng)。 屬于(yu)一種(zhong)補(bu)償元件(jian)(jian)。利(li)用(yong)(yong)其工(gong)作主(zhu)體波(bo)紋管(guan)(guan)(guan)(guan)的有效伸(shen)縮變形，以吸收(shou)管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容器等由(you)熱(re)脹冷(leng)縮等原因(yin)而產生的尺(chi)寸變化，或(huo)補(bu)償管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容器等的軸向(xiang)、橫向(xiang)和角向(xiang)位移。也可用(yong)(yong)于(yu)降噪減振。在現代工(gong)業中用(yong)(yong)途廣(guang)泛。供(gong)(gong)熱(re)上，為了防止供(gong)(gong)熱(re)管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)升溫(wen)時(shi)，由(you)于(yu)熱(re)伸(shen)長或(huo)溫(wen)度(du)應(ying)力而引起管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)變形或(huo)破壞，需要在管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)上設(she)置補(bu)償器，以補(bu)償管(guan)(guan)(guan)(guan)道(dao)(dao)(dao)的熱(re)伸(shen)長，從而減小(xiao)管(guan)(guan)(guan)(guan)壁的應(ying)力和作用(yong)(yong)在閥件(jian)(jian)或(huo)支架結(jie)構上的作用(yong)(yong)力。