膨(peng)脹節習慣上(shang)(shang)也叫補(bu)(bu)償器(qi)，或(huo)(huo)伸(shen)(shen)縮(suo)節。由(you)構成其(qi)工(gong)作(zuo)主體的波(bo)紋(wen)管(guan)(guan)(guan)(一種彈性元件(jian))和端(duan)管(guan)(guan)(guan)、支(zhi)架、法蘭、導(dao)(dao)管(guan)(guan)(guan)等附(fu)件(jian)組成。 膨(peng)脹節是(shi)為(wei)了補(bu)(bu)償因溫度差與機械振動(dong)引起的附(fu)加應(ying)(ying)力(li)(li)，而(er)(er)(er)設置在(zai)容(rong)器(qi)殼體或(huo)(huo)管(guan)(guan)(guan)道上(shang)(shang)的一種撓性結構。利用(yong)其(qi)工(gong)作(zuo)主體波(bo)紋(wen)管(guan)(guan)(guan)的有效伸(shen)(shen)縮(suo)變(bian)(bian)形(xing)(xing)，以吸收管(guan)(guan)(guan)線(xian)、導(dao)(dao)管(guan)(guan)(guan)、容(rong)器(qi)等由(you)熱脹冷縮(suo)等原因而(er)(er)(er)產(chan)生的尺(chi)寸變(bian)(bian)化，或(huo)(huo)補(bu)(bu)償管(guan)(guan)(guan)線(xian)、導(dao)(dao)管(guan)(guan)(guan)、容(rong)器(qi)等的軸向、橫(heng)向和角向位移。也可用(yong)于降噪減振。供熱上(shang)(shang)，為(wei)了防止供熱管(guan)(guan)(guan)道升溫時，由(you)于熱伸(shen)(shen)長或(huo)(huo)溫度應(ying)(ying)力(li)(li)而(er)(er)(er)引起管(guan)(guan)(guan)道變(bian)(bian)形(xing)(xing)或(huo)(huo)破壞，需(xu)要在(zai)管(guan)(guan)(guan)道上(shang)(shang)設置補(bu)(bu)償器(qi)，以補(bu)(bu)償管(guan)(guan)(guan)道的熱伸(shen)(shen)長，從而(er)(er)(er)減小管(guan)(guan)(guan)壁的應(ying)(ying)力(li)(li)和作(zuo)用(yong)在(zai)閥(fa)件(jian)或(huo)(huo)支(zhi)架結構上(shang)(shang)的作(zuo)用(yong)力(li)(li)。