補(bu)(bu)償(chang)器習慣上(shang)也(ye)叫膨脹(zhang)節，或伸(shen)縮(suo)節。由構成(cheng)其工(gong)作(zuo)(zuo)(zuo)主體的(de)(de)(de)波(bo)紋(wen)管(guan)(guan)(guan)（一(yi)種(zhong)彈性元件(jian)(jian)(jian)）和端管(guan)(guan)(guan)、支架(jia)、法蘭、導(dao)管(guan)(guan)(guan)等(deng)附(fu)件(jian)(jian)(jian)組成(cheng)。 屬于一(yi)種(zhong)補(bu)(bu)償(chang)元件(jian)(jian)(jian)。利用(yong)其工(gong)作(zuo)(zuo)(zuo)主體波(bo)紋(wen)管(guan)(guan)(guan)的(de)(de)(de)有效(xiao)伸(shen)縮(suo)變(bian)(bian)形，以(yi)吸收管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)器等(deng)由熱(re)脹(zhang)冷縮(suo)等(deng)原因而產(chan)生(sheng)的(de)(de)(de)尺寸變(bian)(bian)化，或補(bu)(bu)償(chang)管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)器等(deng)的(de)(de)(de)軸向、橫向和角向位(wei)移。也(ye)可用(yong)于降(jiang)噪減振。在現代工(gong)業中(zhong)用(yong)途廣泛。供(gong)熱(re)上(shang)，為(wei)了(le)防(fang)止供(gong)熱(re)管(guan)(guan)(guan)道升溫(wen)時，由于熱(re)伸(shen)長或溫(wen)度應力而引起管(guan)(guan)(guan)道變(bian)(bian)形或破壞，需要(yao)在管(guan)(guan)(guan)道上(shang)設(she)置補(bu)(bu)償(chang)器，以(yi)補(bu)(bu)償(chang)管(guan)(guan)(guan)道的(de)(de)(de)熱(re)伸(shen)長，從而減小(xiao)管(guan)(guan)(guan)壁的(de)(de)(de)應力和作(zuo)(zuo)(zuo)用(yong)在閥件(jian)(jian)(jian)或支架(jia)結構上(shang)的(de)(de)(de)作(zuo)(zuo)(zuo)用(yong)力。