膨(peng)脹節習慣上(shang)也(ye)叫(jiao)補(bu)(bu)(bu)償(chang)器(qi)(qi)，或(huo)(huo)伸縮節。由構成其(qi)(qi)工作主體(ti)的(de)波紋管(guan)(guan)(guan)(guan)(一種(zhong)彈性(xing)元件)和端管(guan)(guan)(guan)(guan)、支架、法蘭、導(dao)管(guan)(guan)(guan)(guan)等(deng)附件組成。 膨(peng)脹節是為了補(bu)(bu)(bu)償(chang)因溫(wen)度差與機(ji)械振動引起(qi)的(de)附加(jia)應(ying)(ying)力(li)，而設置在(zai)容(rong)器(qi)(qi)殼體(ti)或(huo)(huo)管(guan)(guan)(guan)(guan)道上(shang)的(de)一種(zhong)撓性(xing)結構。利用(yong)(yong)其(qi)(qi)工作主體(ti)波紋管(guan)(guan)(guan)(guan)的(de)有效伸縮變(bian)形，以(yi)吸收(shou)管(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等(deng)由熱(re)脹冷縮等(deng)原因而產生的(de)尺寸(cun)變(bian)化，或(huo)(huo)補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等(deng)的(de)軸向、橫(heng)向和角向位(wei)移。也(ye)可用(yong)(yong)于(yu)降噪減振。供(gong)熱(re)上(shang)，為了防(fang)止供(gong)熱(re)管(guan)(guan)(guan)(guan)道升溫(wen)時，由于(yu)熱(re)伸長(chang)或(huo)(huo)溫(wen)度應(ying)(ying)力(li)而引起(qi)管(guan)(guan)(guan)(guan)道變(bian)形或(huo)(huo)破壞(huai)，需要(yao)在(zai)管(guan)(guan)(guan)(guan)道上(shang)設置補(bu)(bu)(bu)償(chang)器(qi)(qi)，以(yi)補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)道的(de)熱(re)伸長(chang)，從而減小(xiao)管(guan)(guan)(guan)(guan)壁的(de)應(ying)(ying)力(li)和作用(yong)(yong)在(zai)閥件或(huo)(huo)支架結構上(shang)的(de)作用(yong)(yong)力(li)。