膨脹(zhang)節習慣上(shang)也(ye)叫補(bu)償(chang)器，或伸縮(suo)節。由(you)構(gou)成其工(gong)(gong)作(zuo)主體的(de)(de)(de)波紋管(guan)(guan)(guan)(guan)(一(yi)種彈(dan)性(xing)元(yuan)件(jian))和端(duan)管(guan)(guan)(guan)(guan)、支架(jia)、法(fa)蘭、導管(guan)(guan)(guan)(guan)等附件(jian)組成。 膨脹(zhang)節是為了補(bu)償(chang)因溫(wen)度差與機(ji)械振動(dong)引起的(de)(de)(de)附加應(ying)力(li)，而設(she)置在容器殼(ke)體或管(guan)(guan)(guan)(guan)道上(shang)的(de)(de)(de)一(yi)種撓性(xing)結(jie)構(gou)。利用其工(gong)(gong)作(zuo)主體波紋管(guan)(guan)(guan)(guan)的(de)(de)(de)有效(xiao)伸縮(suo)變形，以吸收管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容器等由(you)熱脹(zhang)冷縮(suo)等原因而產生(sheng)的(de)(de)(de)尺寸變化，或補(bu)償(chang)管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容器等的(de)(de)(de)軸向(xiang)(xiang)、橫向(xiang)(xiang)和角向(xiang)(xiang)位移。也(ye)可(ke)用于(yu)(yu)降噪減(jian)振。供(gong)熱上(shang)，為了防止供(gong)熱管(guan)(guan)(guan)(guan)道升溫(wen)時，由(you)于(yu)(yu)熱伸長或溫(wen)度應(ying)力(li)而引起管(guan)(guan)(guan)(guan)道變形或破壞，需要在管(guan)(guan)(guan)(guan)道上(shang)設(she)置補(bu)償(chang)器，以補(bu)償(chang)管(guan)(guan)(guan)(guan)道的(de)(de)(de)熱伸長，從而減(jian)小管(guan)(guan)(guan)(guan)壁的(de)(de)(de)應(ying)力(li)和作(zuo)用在閥(fa)件(jian)或支架(jia)結(jie)構(gou)上(shang)的(de)(de)(de)作(zuo)用力(li)。