補(bu)償器習慣上(shang)也叫膨脹節，或伸(shen)(shen)縮(suo)節。由構成(cheng)其工(gong)作主(zhu)(zhu)體(ti)的(de)波(bo)(bo)紋管(guan)(guan)(guan)（一(yi)種彈(dan)性元件(jian)）和端管(guan)(guan)(guan)、支(zhi)架(jia)、法蘭、導管(guan)(guan)(guan)等(deng)附件(jian)組(zu)成(cheng)。 屬(shu)于(yu)一(yi)種補(bu)償元件(jian)。利用(yong)其工(gong)作主(zhu)(zhu)體(ti)波(bo)(bo)紋管(guan)(guan)(guan)的(de)有(you)效伸(shen)(shen)縮(suo)變(bian)形，以(yi)吸(xi)收(shou)管(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)、容(rong)器等(deng)由熱脹冷縮(suo)等(deng)原因而(er)(er)產生(sheng)的(de)尺寸(cun)變(bian)化(hua)，或補(bu)償管(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)、容(rong)器等(deng)的(de)軸向、橫向和角向位移。也可用(yong)于(yu)降噪減(jian)振。在(zai)現代(dai)工(gong)業中用(yong)途廣泛。供熱上(shang)，為了防(fang)止供熱管(guan)(guan)(guan)道(dao)升溫(wen)時，由于(yu)熱伸(shen)(shen)長(chang)或溫(wen)度應力而(er)(er)引起管(guan)(guan)(guan)道(dao)變(bian)形或破壞，需要在(zai)管(guan)(guan)(guan)道(dao)上(shang)設置補(bu)償器，以(yi)補(bu)償管(guan)(guan)(guan)道(dao)的(de)熱伸(shen)(shen)長(chang)，從而(er)(er)減(jian)小管(guan)(guan)(guan)壁的(de)應力和作用(yong)在(zai)閥件(jian)或支(zhi)架(jia)結構上(shang)的(de)作用(yong)力。