膨(peng)(peng)脹節習(xi)慣上(shang)(shang)也叫補(bu)償(chang)(chang)器，或(huo)(huo)伸(shen)縮(suo)(suo)節。由構成其(qi)工(gong)作(zuo)主體的(de)波紋管(guan)(guan)(guan)(一種(zhong)彈(dan)性元件(jian)(jian))和(he)端(duan)管(guan)(guan)(guan)、支架、法蘭(lan)、導管(guan)(guan)(guan)等(deng)(deng)附(fu)件(jian)(jian)組(zu)成。 膨(peng)(peng)脹節是為了補(bu)償(chang)(chang)因(yin)溫度(du)差與機械振動引起的(de)附(fu)加應力，而設(she)置(zhi)在容(rong)器殼體或(huo)(huo)管(guan)(guan)(guan)道(dao)上(shang)(shang)的(de)一種(zhong)撓性結構。利用(yong)(yong)其(qi)工(gong)作(zuo)主體波紋管(guan)(guan)(guan)的(de)有效伸(shen)縮(suo)(suo)變(bian)(bian)形，以吸收管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器等(deng)(deng)由熱(re)脹冷縮(suo)(suo)等(deng)(deng)原因(yin)而產生的(de)尺(chi)寸變(bian)(bian)化，或(huo)(huo)補(bu)償(chang)(chang)管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器等(deng)(deng)的(de)軸向、橫(heng)向和(he)角(jiao)向位移。也可用(yong)(yong)于(yu)降噪減(jian)振。供熱(re)上(shang)(shang)，為了防止供熱(re)管(guan)(guan)(guan)道(dao)升溫時，由于(yu)熱(re)伸(shen)長或(huo)(huo)溫度(du)應力而引起管(guan)(guan)(guan)道(dao)變(bian)(bian)形或(huo)(huo)破壞，需(xu)要在管(guan)(guan)(guan)道(dao)上(shang)(shang)設(she)置(zhi)補(bu)償(chang)(chang)器，以補(bu)償(chang)(chang)管(guan)(guan)(guan)道(dao)的(de)熱(re)伸(shen)長，從而減(jian)小管(guan)(guan)(guan)壁(bi)的(de)應力和(he)作(zuo)用(yong)(yong)在閥件(jian)(jian)或(huo)(huo)支架結構上(shang)(shang)的(de)作(zuo)用(yong)(yong)力。