補(bu)(bu)償(chang)器(qi)(qi)習慣上(shang)也叫(jiao)膨脹節(jie)，或伸(shen)(shen)縮節(jie)。由(you)(you)構(gou)成(cheng)其(qi)工作主(zhu)(zhu)體(ti)的(de)(de)波紋(wen)管(guan)(guan)(guan)(guan)（一種彈性元件(jian)(jian)）和端管(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導(dao)管(guan)(guan)(guan)(guan)等(deng)附(fu)件(jian)(jian)組成(cheng)。 屬于一種補(bu)(bu)償(chang)元件(jian)(jian)。利用(yong)其(qi)工作主(zhu)(zhu)體(ti)波紋(wen)管(guan)(guan)(guan)(guan)的(de)(de)有(you)效(xiao)伸(shen)(shen)縮變形，以吸收(shou)管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由(you)(you)熱(re)脹冷縮等(deng)原因而(er)產生(sheng)的(de)(de)尺寸(cun)變化，或補(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的(de)(de)軸(zhou)向、橫(heng)向和角向位移。也可用(yong)于降噪減振。在現代工業中用(yong)途廣泛。供(gong)(gong)熱(re)上(shang)，為了防止(zhi)供(gong)(gong)熱(re)管(guan)(guan)(guan)(guan)道升溫時，由(you)(you)于熱(re)伸(shen)(shen)長或溫度應力而(er)引(yin)起管(guan)(guan)(guan)(guan)道變形或破壞(huai)，需(xu)要在管(guan)(guan)(guan)(guan)道上(shang)設置補(bu)(bu)償(chang)器(qi)(qi)，以補(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)道的(de)(de)熱(re)伸(shen)(shen)長，從而(er)減小管(guan)(guan)(guan)(guan)壁的(de)(de)應力和作用(yong)在閥(fa)件(jian)(jian)或支(zhi)架結(jie)構(gou)上(shang)的(de)(de)作用(yong)力。