補償器習慣上也叫膨脹節，或伸縮節。由構成其工作主體的波紋管（一種彈性元件）和端管、支架、法蘭、導管等附件組成。膨脹節廠家 屬于一種補(bu)償(chang)元件。利用(yong)(yong)其(qi)工(gong)作(zuo)(zuo)(zuo)主體波紋管(guan)(guan)(guan)的有(you)效(xiao)伸(shen)縮變(bian)形，以吸收管(guan)(guan)(guan)線、導(dao)(dao)管(guan)(guan)(guan)、容器(qi)(qi)等由(you)熱(re)(re)脹(zhang)冷(leng)縮等原因而(er)(er)產生的尺寸變(bian)化，或(huo)補(bu)償(chang)管(guan)(guan)(guan)線、導(dao)(dao)管(guan)(guan)(guan)、容器(qi)(qi)等的軸向(xiang)、橫向(xiang)和(he)角向(xiang)位移。也(ye)可用(yong)(yong)于降噪減振。在現(xian)代工(gong)業中用(yong)(yong)途廣(guang)泛。供熱(re)(re)上(shang)(shang)，為了防(fang)止供熱(re)(re)管(guan)(guan)(guan)道(dao)升(sheng)溫時，由(you)于熱(re)(re)伸(shen)長或(huo)溫度應力而(er)(er)引起管(guan)(guan)(guan)道(dao)變(bian)形或(huo)破壞(huai)，需要在管(guan)(guan)(guan)道(dao)上(shang)(shang)設置補(bu)償(chang)器(qi)(qi)，以補(bu)償(chang)管(guan)(guan)(guan)道(dao)的熱(re)(re)伸(shen)長，從(cong)而(er)(er)減小管(guan)(guan)(guan)壁(bi)的應力和(he)作(zuo)(zuo)(zuo)用(yong)(yong)在閥件或(huo)支架結構上(shang)(shang)的作(zuo)(zuo)(zuo)用(yong)(yong)力。