補(bu)(bu)償器(qi)習慣上(shang)也(ye)叫(jiao)膨脹節，或伸(shen)縮節。由(you)構(gou)成其(qi)工作(zuo)主體的波紋管(guan)(guan)(guan)(guan)(guan)（一種彈性元件(jian)(jian)）和端(duan)管(guan)(guan)(guan)(guan)(guan)、支架、法蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)等(deng)附件(jian)(jian)組成。 屬于一種補(bu)(bu)償元件(jian)(jian)。利用其(qi)工作(zuo)主體波紋管(guan)(guan)(guan)(guan)(guan)的有效伸(shen)縮變形，以吸收管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)由(you)熱(re)脹冷縮等(deng)原因而產(chan)生(sheng)的尺寸變化(hua)，或補(bu)(bu)償管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)的軸向(xiang)、橫向(xiang)和角向(xiang)位移。也(ye)可用于降噪減(jian)振。在現代工業中用途廣泛。供(gong)熱(re)上(shang)，為了防止供(gong)熱(re)管(guan)(guan)(guan)(guan)(guan)道(dao)升溫(wen)時，由(you)于熱(re)伸(shen)長(chang)或溫(wen)度應力而引起管(guan)(guan)(guan)(guan)(guan)道(dao)變形或破(po)壞(huai)，需(xu)要在管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)設置補(bu)(bu)償器(qi)，以補(bu)(bu)償管(guan)(guan)(guan)(guan)(guan)道(dao)的熱(re)伸(shen)長(chang)，從(cong)而減(jian)小管(guan)(guan)(guan)(guan)(guan)壁的應力和作(zuo)用在閥件(jian)(jian)或支架結(jie)構(gou)上(shang)的作(zuo)用力。