膨脹節習慣上(shang)也叫補償器(qi)，或伸縮節。由(you)構成(cheng)其工(gong)作(zuo)主(zhu)體(ti)的(de)(de)波紋管(guan)(guan)(guan)(guan)(guan)(guan)(一(yi)種彈性(xing)(xing)元件)和(he)端管(guan)(guan)(guan)(guan)(guan)(guan)、支(zhi)架、法(fa)蘭、導(dao)(dao)(dao)管(guan)(guan)(guan)(guan)(guan)(guan)等附件組成(cheng)。 膨脹節是為(wei)了補償因溫度差與機械(xie)振動引(yin)起(qi)(qi)的(de)(de)附加(jia)應力(li)，而(er)設(she)置在容器(qi)殼(ke)體(ti)或管(guan)(guan)(guan)(guan)(guan)(guan)道上(shang)的(de)(de)一(yi)種撓性(xing)(xing)結構。利用其工(gong)作(zuo)主(zhu)體(ti)波紋管(guan)(guan)(guan)(guan)(guan)(guan)的(de)(de)有效伸縮變形(xing)，以(yi)吸(xi)收管(guan)(guan)(guan)(guan)(guan)(guan)線(xian)、導(dao)(dao)(dao)管(guan)(guan)(guan)(guan)(guan)(guan)、容器(qi)等由(you)熱(re)(re)脹冷(leng)縮等原因而(er)產生(sheng)的(de)(de)尺寸(cun)變化，或補償管(guan)(guan)(guan)(guan)(guan)(guan)線(xian)、導(dao)(dao)(dao)管(guan)(guan)(guan)(guan)(guan)(guan)、容器(qi)等的(de)(de)軸向、橫向和(he)角向位移。也可用于降噪減(jian)振。供(gong)熱(re)(re)上(shang)，為(wei)了防止供(gong)熱(re)(re)管(guan)(guan)(guan)(guan)(guan)(guan)道升(sheng)溫時，由(you)于熱(re)(re)伸長或溫度應力(li)而(er)引(yin)起(qi)(qi)管(guan)(guan)(guan)(guan)(guan)(guan)道變形(xing)或破壞，需要在管(guan)(guan)(guan)(guan)(guan)(guan)道上(shang)設(she)置補償器(qi)，以(yi)補償管(guan)(guan)(guan)(guan)(guan)(guan)道的(de)(de)熱(re)(re)伸長，從而(er)減(jian)小管(guan)(guan)(guan)(guan)(guan)(guan)壁的(de)(de)應力(li)和(he)作(zuo)用在閥件或支(zhi)架結構上(shang)的(de)(de)作(zuo)用力(li)。