膨脹(zhang)(zhang)節習慣上也叫補(bu)償(chang)(chang)(chang)器(qi)(qi)，或伸(shen)(shen)縮(suo)節。由構成其工(gong)作(zuo)(zuo)(zuo)主體(ti)(ti)的(de)(de)波紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)(一種彈性(xing)(xing)元件(jian))和端管(guan)(guan)(guan)(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導管(guan)(guan)(guan)(guan)(guan)(guan)(guan)等附件(jian)組(zu)成。 膨脹(zhang)(zhang)節是(shi)為了補(bu)償(chang)(chang)(chang)因(yin)溫(wen)度差與機(ji)械振動引起的(de)(de)附加應力(li)，而(er)設置在容器(qi)(qi)殼體(ti)(ti)或管(guan)(guan)(guan)(guan)(guan)(guan)(guan)道(dao)(dao)上的(de)(de)一種撓性(xing)(xing)結(jie)構。利(li)用(yong)其工(gong)作(zuo)(zuo)(zuo)主體(ti)(ti)波紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)的(de)(de)有效伸(shen)(shen)縮(suo)變形，以吸收管(guan)(guan)(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等由熱(re)(re)脹(zhang)(zhang)冷縮(suo)等原因(yin)而(er)產生的(de)(de)尺寸變化，或補(bu)償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等的(de)(de)軸向(xiang)(xiang)、橫向(xiang)(xiang)和角(jiao)向(xiang)(xiang)位移。也可用(yong)于降噪減振。供熱(re)(re)上，為了防止供熱(re)(re)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)道(dao)(dao)升溫(wen)時，由于熱(re)(re)伸(shen)(shen)長(chang)或溫(wen)度應力(li)而(er)引起管(guan)(guan)(guan)(guan)(guan)(guan)(guan)道(dao)(dao)變形或破(po)壞，需(xu)要在管(guan)(guan)(guan)(guan)(guan)(guan)(guan)道(dao)(dao)上設置補(bu)償(chang)(chang)(chang)器(qi)(qi)，以補(bu)償(chang)(chang)(chang)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)道(dao)(dao)的(de)(de)熱(re)(re)伸(shen)(shen)長(chang)，從(cong)而(er)減小(xiao)管(guan)(guan)(guan)(guan)(guan)(guan)(guan)壁(bi)的(de)(de)應力(li)和作(zuo)(zuo)(zuo)用(yong)在閥件(jian)或支(zhi)架結(jie)構上的(de)(de)作(zuo)(zuo)(zuo)用(yong)力(li)。