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(shu)于一種補償元件。利用(yong)其工作(zuo)主體波紋管(guan)(guan)(guan)(guan)(guan)(guan)的(de)有效伸(shen)縮變形，以吸收管(guan)(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)(guan)、容(rong)器等(deng)由(you)(you)熱(re)(re)脹冷縮等(deng)原因而產生(sheng)的(de)尺寸變化(hua)，或補償管(guan)(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)(guan)、容(rong)器等(deng)的(de)軸向(xiang)、橫向(xiang)和(he)角向(xiang)位移。也可用(yong)于降噪減(jian)振。在(zai)現代工業(ye)中用(yong)途廣泛。供熱(re)(re)上，為(wei)了防(fang)止供熱(re)(re)管(guan)(guan)(guan)(guan)(guan)(guan)道升(sheng)溫時(shi)，由(you)(you)于熱(re)(re)伸(shen)長(chang)或溫度應(ying)力(li)而引起管(guan)(guan)(guan)(guan)(guan)(guan)道變形或破壞，需要(yao)在(zai)管(guan)(guan)(guan)(guan)(guan)(guan)道上設置補償器，以補償管(guan)(guan)(guan)(guan)(guan)(guan)道的(de)熱(re)(re)伸(shen)長(chang)，從而減(jian)小管(guan)(guan)(guan)(guan)(guan)(guan)壁(bi)的(de)應(ying)力(li)和(he)作(zuo)用(yong)在(zai)閥件或支架結(jie)構上的(de)作(zuo)用(yong)力(li)。