膨脹節習(xi)慣上(shang)也(ye)叫補(bu)償(chang)(chang)器(qi)，或伸縮(suo)節。由(you)構成其工作(zuo)(zuo)主體(ti)的(de)(de)(de)波(bo)紋(wen)管(guan)(guan)(guan)(guan)(guan)(一(yi)種(zhong)彈性(xing)元件(jian)(jian))和端(duan)管(guan)(guan)(guan)(guan)(guan)、支(zhi)架、法(fa)蘭、導管(guan)(guan)(guan)(guan)(guan)等(deng)附(fu)件(jian)(jian)組成。 膨脹節是(shi)為了補(bu)償(chang)(chang)因溫(wen)度(du)差與機(ji)械振(zhen)動引(yin)起的(de)(de)(de)附(fu)加應力(li)，而設置(zhi)在容器(qi)殼體(ti)或管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)的(de)(de)(de)一(yi)種(zhong)撓性(xing)結構。利用(yong)(yong)其工作(zuo)(zuo)主體(ti)波(bo)紋(wen)管(guan)(guan)(guan)(guan)(guan)的(de)(de)(de)有效伸縮(suo)變(bian)(bian)形，以(yi)(yi)吸收管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)由(you)熱脹冷縮(suo)等(deng)原因而產生的(de)(de)(de)尺寸變(bian)(bian)化，或補(bu)償(chang)(chang)管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)的(de)(de)(de)軸向(xiang)、橫(heng)向(xiang)和角向(xiang)位(wei)移。也(ye)可用(yong)(yong)于降噪減振(zhen)。供熱上(shang)，為了防止供熱管(guan)(guan)(guan)(guan)(guan)道(dao)升溫(wen)時，由(you)于熱伸長或溫(wen)度(du)應力(li)而引(yin)起管(guan)(guan)(guan)(guan)(guan)道(dao)變(bian)(bian)形或破壞(huai)，需(xu)要(yao)在管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)設置(zhi)補(bu)償(chang)(chang)器(qi)，以(yi)(yi)補(bu)償(chang)(chang)管(guan)(guan)(guan)(guan)(guan)道(dao)的(de)(de)(de)熱伸長，從而減小管(guan)(guan)(guan)(guan)(guan)壁(bi)的(de)(de)(de)應力(li)和作(zuo)(zuo)用(yong)(yong)在閥件(jian)(jian)或支(zhi)架結構上(shang)的(de)(de)(de)作(zuo)(zuo)用(yong)(yong)力(li)。