膨脹節(jie)習慣上(shang)(shang)也叫(jiao)補償器，或(huo)伸(shen)縮節(jie)。由(you)(you)構(gou)成(cheng)其工作主體(ti)的(de)(de)波紋(wen)管(guan)(guan)(guan)(guan)(一種(zhong)彈性(xing)元件)和(he)端管(guan)(guan)(guan)(guan)、支(zhi)架(jia)(jia)、法蘭、導管(guan)(guan)(guan)(guan)等附件組成(cheng)。 膨脹節(jie)是為了補償因溫度(du)差與機械振動引(yin)起(qi)的(de)(de)附加應力(li)，而(er)(er)(er)設置在(zai)容(rong)器殼(ke)體(ti)或(huo)管(guan)(guan)(guan)(guan)道上(shang)(shang)的(de)(de)一種(zhong)撓(nao)性(xing)結構(gou)。利用(yong)(yong)其工作主體(ti)波紋(wen)管(guan)(guan)(guan)(guan)的(de)(de)有效伸(shen)縮變(bian)(bian)形(xing)，以吸收管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容(rong)器等由(you)(you)熱(re)脹冷縮等原因而(er)(er)(er)產生(sheng)的(de)(de)尺(chi)寸變(bian)(bian)化，或(huo)補償管(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)、容(rong)器等的(de)(de)軸向(xiang)、橫向(xiang)和(he)角向(xiang)位移(yi)。也可用(yong)(yong)于降噪減振。供(gong)熱(re)上(shang)(shang)，為了防(fang)止供(gong)熱(re)管(guan)(guan)(guan)(guan)道升溫時(shi)，由(you)(you)于熱(re)伸(shen)長(chang)或(huo)溫度(du)應力(li)而(er)(er)(er)引(yin)起(qi)管(guan)(guan)(guan)(guan)道變(bian)(bian)形(xing)或(huo)破壞(huai)，需要在(zai)管(guan)(guan)(guan)(guan)道上(shang)(shang)設置補償器，以補償管(guan)(guan)(guan)(guan)道的(de)(de)熱(re)伸(shen)長(chang)，從而(er)(er)(er)減小(xiao)管(guan)(guan)(guan)(guan)壁(bi)的(de)(de)應力(li)和(he)作用(yong)(yong)在(zai)閥件或(huo)支(zhi)架(jia)(jia)結構(gou)上(shang)(shang)的(de)(de)作用(yong)(yong)力(li)。