膨(peng)脹節習慣上(shang)也叫(jiao)補(bu)償(chang)器，或伸(shen)縮(suo)節。由構(gou)(gou)成(cheng)其工作主體(ti)的(de)(de)波(bo)紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)(一種彈性元(yuan)件(jian))和(he)端管(guan)(guan)(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導管(guan)(guan)(guan)(guan)(guan)(guan)等(deng)(deng)附件(jian)組成(cheng)。 膨(peng)脹節是為了補(bu)償(chang)因(yin)溫(wen)度差(cha)與機械振動引(yin)起的(de)(de)附加應(ying)(ying)力(li)，而設置(zhi)在(zai)容(rong)器殼(ke)體(ti)或管(guan)(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)的(de)(de)一種撓性結(jie)構(gou)(gou)。利用(yong)其工作主體(ti)波(bo)紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)的(de)(de)有效伸(shen)縮(suo)變形(xing)，以吸收管(guan)(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)(guan)、容(rong)器等(deng)(deng)由熱(re)(re)脹冷縮(suo)等(deng)(deng)原因(yin)而產生的(de)(de)尺(chi)寸變化(hua)，或補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)(guan)、容(rong)器等(deng)(deng)的(de)(de)軸向(xiang)、橫(heng)向(xiang)和(he)角向(xiang)位移。也可用(yong)于(yu)降噪(zao)減(jian)振。供熱(re)(re)上(shang)，為了防止供熱(re)(re)管(guan)(guan)(guan)(guan)(guan)(guan)道(dao)升(sheng)溫(wen)時(shi)，由于(yu)熱(re)(re)伸(shen)長或溫(wen)度應(ying)(ying)力(li)而引(yin)起管(guan)(guan)(guan)(guan)(guan)(guan)道(dao)變形(xing)或破壞，需要在(zai)管(guan)(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)設置(zhi)補(bu)償(chang)器，以補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)(guan)道(dao)的(de)(de)熱(re)(re)伸(shen)長，從而減(jian)小管(guan)(guan)(guan)(guan)(guan)(guan)壁的(de)(de)應(ying)(ying)力(li)和(he)作用(yong)在(zai)閥件(jian)或支(zhi)架結(jie)構(gou)(gou)上(shang)的(de)(de)作用(yong)力(li)。