膨(peng)脹(zhang)節習慣上(shang)(shang)也叫補(bu)償(chang)器，或(huo)(huo)伸(shen)縮節。由構(gou)成其(qi)工作(zuo)主體(ti)的波紋管(guan)(guan)(guan)(guan)(guan)(一種彈(dan)性(xing)(xing)元件(jian))和端管(guan)(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導管(guan)(guan)(guan)(guan)(guan)等附件(jian)組成。 膨(peng)脹(zhang)節是為了補(bu)償(chang)因溫(wen)(wen)度差與機械振動引(yin)起的附加應力(li)，而(er)設置在(zai)容(rong)器殼體(ti)或(huo)(huo)管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)(shang)的一種撓(nao)性(xing)(xing)結構(gou)。利(li)用(yong)其(qi)工作(zuo)主體(ti)波紋管(guan)(guan)(guan)(guan)(guan)的有(you)效伸(shen)縮變形，以吸收管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容(rong)器等由熱脹(zhang)冷縮等原因而(er)產生的尺(chi)寸變化(hua)，或(huo)(huo)補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容(rong)器等的軸向、橫向和角向位移(yi)。也可用(yong)于降(jiang)噪減振。供(gong)熱上(shang)(shang)，為了防止供(gong)熱管(guan)(guan)(guan)(guan)(guan)道(dao)升溫(wen)(wen)時，由于熱伸(shen)長或(huo)(huo)溫(wen)(wen)度應力(li)而(er)引(yin)起管(guan)(guan)(guan)(guan)(guan)道(dao)變形或(huo)(huo)破壞(huai)，需要在(zai)管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)(shang)設置補(bu)償(chang)器，以補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)道(dao)的熱伸(shen)長，從而(er)減小管(guan)(guan)(guan)(guan)(guan)壁(bi)的應力(li)和作(zuo)用(yong)在(zai)閥件(jian)或(huo)(huo)支(zhi)架結構(gou)上(shang)(shang)的作(zuo)用(yong)力(li)。