補(bu)償(chang)器(qi)(qi)習慣(guan)上(shang)也(ye)叫膨脹節，或(huo)(huo)伸(shen)(shen)縮節。由構(gou)成(cheng)其工(gong)作主體(ti)的(de)波紋管(guan)(guan)(guan)(guan)（一(yi)種彈性元件(jian)）和(he)端管(guan)(guan)(guan)(guan)、支架、法(fa)蘭(lan)、導管(guan)(guan)(guan)(guan)等(deng)附件(jian)組成(cheng)。 屬于(yu)一(yi)種補(bu)償(chang)元件(jian)。利(li)用(yong)(yong)(yong)其工(gong)作主體(ti)波紋管(guan)(guan)(guan)(guan)的(de)有效伸(shen)(shen)縮變形(xing)(xing)，以(yi)吸(xi)收管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由熱(re)脹冷縮等(deng)原因而產生的(de)尺寸變化，或(huo)(huo)補(bu)償(chang)管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的(de)軸向、橫(heng)向和(he)角向位移(yi)。也(ye)可用(yong)(yong)(yong)于(yu)降噪減振(zhen)。在現代工(gong)業中(zhong)用(yong)(yong)(yong)途(tu)廣泛。供熱(re)上(shang)，為了防(fang)止供熱(re)管(guan)(guan)(guan)(guan)道(dao)升溫時(shi)，由于(yu)熱(re)伸(shen)(shen)長(chang)或(huo)(huo)溫度(du)應力而引起管(guan)(guan)(guan)(guan)道(dao)變形(xing)(xing)或(huo)(huo)破(po)壞(huai)，需要在管(guan)(guan)(guan)(guan)道(dao)上(shang)設置(zhi)補(bu)償(chang)器(qi)(qi)，以(yi)補(bu)償(chang)管(guan)(guan)(guan)(guan)道(dao)的(de)熱(re)伸(shen)(shen)長(chang)，從而減小管(guan)(guan)(guan)(guan)壁的(de)應力和(he)作用(yong)(yong)(yong)在閥(fa)件(jian)或(huo)(huo)支架結構(gou)上(shang)的(de)作用(yong)(yong)(yong)力。