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)(chang)元件。利用(yong)(yong)其工(gong)(gong)作主體波紋管(guan)(guan)(guan)的(de)有(you)效伸縮變(bian)(bian)(bian)形，以(yi)吸收管(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)、容器等(deng)由熱(re)(re)(re)脹冷(leng)縮等(deng)原因而產(chan)生的(de)尺寸變(bian)(bian)(bian)化，或補(bu)償(chang)(chang)管(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)、容器等(deng)的(de)軸向、橫向和(he)角向位移(yi)。也可(ke)用(yong)(yong)于降噪減振。在(zai)現代工(gong)(gong)業中用(yong)(yong)途廣泛。供(gong)熱(re)(re)(re)上(shang)，為(wei)了防止供(gong)熱(re)(re)(re)管(guan)(guan)(guan)道(dao)升溫時，由于熱(re)(re)(re)伸長或溫度應(ying)力而引(yin)起管(guan)(guan)(guan)道(dao)變(bian)(bian)(bian)形或破(po)壞，需要(yao)在(zai)管(guan)(guan)(guan)道(dao)上(shang)設置補(bu)償(chang)(chang)器，以(yi)補(bu)償(chang)(chang)管(guan)(guan)(guan)道(dao)的(de)熱(re)(re)(re)伸長，從(cong)而減小管(guan)(guan)(guan)壁的(de)應(ying)力和(he)作用(yong)(yong)在(zai)閥件或支架結構上(shang)的(de)作用(yong)(yong)力。