膨脹(zhang)節習(xi)慣(guan)上(shang)也叫補(bu)償器，或(huo)(huo)伸(shen)縮節。由構成(cheng)其工(gong)作(zuo)(zuo)(zuo)主(zhu)體的(de)波紋管(guan)(guan)(guan)(guan)(guan)(一種(zhong)(zhong)彈性元(yuan)件)和端管(guan)(guan)(guan)(guan)(guan)、支架(jia)、法(fa)蘭、導管(guan)(guan)(guan)(guan)(guan)等(deng)附(fu)件組成(cheng)。 膨脹(zhang)節是為(wei)了(le)補(bu)償因溫度差與機(ji)械振動引起的(de)附(fu)加應(ying)(ying)力(li)(li)，而(er)(er)設置在(zai)容器殼體或(huo)(huo)管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)上(shang)的(de)一種(zhong)(zhong)撓性結(jie)構。利用(yong)其工(gong)作(zuo)(zuo)(zuo)主(zhu)體波紋管(guan)(guan)(guan)(guan)(guan)的(de)有效(xiao)伸(shen)縮變(bian)(bian)(bian)形，以吸收(shou)管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器等(deng)由熱(re)脹(zhang)冷縮等(deng)原因而(er)(er)產生的(de)尺寸變(bian)(bian)(bian)化(hua)，或(huo)(huo)補(bu)償管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器等(deng)的(de)軸向(xiang)、橫向(xiang)和角向(xiang)位移。也可用(yong)于降噪(zao)減(jian)振。供熱(re)上(shang)，為(wei)了(le)防止供熱(re)管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)升溫時，由于熱(re)伸(shen)長或(huo)(huo)溫度應(ying)(ying)力(li)(li)而(er)(er)引起管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)變(bian)(bian)(bian)形或(huo)(huo)破壞，需要在(zai)管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)上(shang)設置補(bu)償器，以補(bu)償管(guan)(guan)(guan)(guan)(guan)道(dao)(dao)的(de)熱(re)伸(shen)長，從而(er)(er)減(jian)小管(guan)(guan)(guan)(guan)(guan)壁的(de)應(ying)(ying)力(li)(li)和作(zuo)(zuo)(zuo)用(yong)在(zai)閥件或(huo)(huo)支架(jia)結(jie)構上(shang)的(de)作(zuo)(zuo)(zuo)用(yong)力(li)(li)。