膨脹(zhang)(zhang)節習慣上(shang)(shang)(shang)也叫補(bu)償器(qi)(qi)(qi)(qi)，或伸(shen)縮(suo)節。由(you)構(gou)成(cheng)其工(gong)(gong)作(zuo)主(zhu)體(ti)(ti)的波紋管(guan)(guan)(guan)(一種彈性元(yuan)件(jian)(jian))和(he)端管(guan)(guan)(guan)、支架、法(fa)蘭、導(dao)管(guan)(guan)(guan)等附(fu)件(jian)(jian)組成(cheng)。 膨脹(zhang)(zhang)節是為了補(bu)償因(yin)溫度(du)差與機(ji)械振(zhen)動引起(qi)的附(fu)加(jia)應力(li)(li)，而(er)設(she)置在容(rong)(rong)器(qi)(qi)(qi)(qi)殼體(ti)(ti)或管(guan)(guan)(guan)道(dao)上(shang)(shang)(shang)的一種撓性結構(gou)。利用(yong)(yong)其工(gong)(gong)作(zuo)主(zhu)體(ti)(ti)波紋管(guan)(guan)(guan)的有效伸(shen)縮(suo)變形(xing)，以吸收管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)(rong)器(qi)(qi)(qi)(qi)等由(you)熱(re)脹(zhang)(zhang)冷縮(suo)等原因(yin)而(er)產生的尺寸變化，或補(bu)償管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)(rong)器(qi)(qi)(qi)(qi)等的軸向、橫向和(he)角向位移。也可用(yong)(yong)于降噪減振(zhen)。供熱(re)上(shang)(shang)(shang)，為了防止供熱(re)管(guan)(guan)(guan)道(dao)升溫時，由(you)于熱(re)伸(shen)長(chang)或溫度(du)應力(li)(li)而(er)引起(qi)管(guan)(guan)(guan)道(dao)變形(xing)或破(po)壞，需要在管(guan)(guan)(guan)道(dao)上(shang)(shang)(shang)設(she)置補(bu)償器(qi)(qi)(qi)(qi)，以補(bu)償管(guan)(guan)(guan)道(dao)的熱(re)伸(shen)長(chang)，從而(er)減小管(guan)(guan)(guan)壁的應力(li)(li)和(he)作(zuo)用(yong)(yong)在閥件(jian)(jian)或支架結構(gou)上(shang)(shang)(shang)的作(zuo)用(yong)(yong)力(li)(li)。