補(bu)償(chang)(chang)器(qi)習慣上(shang)也叫膨脹節，或(huo)伸縮節。由(you)構成其工作主(zhu)體(ti)的(de)波(bo)紋管(guan)(guan)(guan)（一種彈性元(yuan)件(jian)(jian)(jian)）和(he)端管(guan)(guan)(guan)、支架、法(fa)蘭、導管(guan)(guan)(guan)等(deng)(deng)附件(jian)(jian)(jian)組成。 屬(shu)于一種補(bu)償(chang)(chang)元(yuan)件(jian)(jian)(jian)。利用(yong)(yong)其工作主(zhu)體(ti)波(bo)紋管(guan)(guan)(guan)的(de)有效(xiao)伸縮變形(xing)，以(yi)吸收管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容器(qi)等(deng)(deng)由(you)熱脹冷縮等(deng)(deng)原因而產生(sheng)的(de)尺(chi)寸變化，或(huo)補(bu)償(chang)(chang)管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容器(qi)等(deng)(deng)的(de)軸向、橫向和(he)角向位移。也可用(yong)(yong)于降噪減(jian)振。在(zai)現(xian)代(dai)工業中(zhong)用(yong)(yong)途廣泛。供熱上(shang)，為了防止供熱管(guan)(guan)(guan)道升溫(wen)(wen)時，由(you)于熱伸長(chang)或(huo)溫(wen)(wen)度(du)應力而引起管(guan)(guan)(guan)道變形(xing)或(huo)破壞，需要在(zai)管(guan)(guan)(guan)道上(shang)設置(zhi)補(bu)償(chang)(chang)器(qi)，以(yi)補(bu)償(chang)(chang)管(guan)(guan)(guan)道的(de)熱伸長(chang)，從而減(jian)小(xiao)管(guan)(guan)(guan)壁的(de)應力和(he)作用(yong)(yong)在(zai)閥件(jian)(jian)(jian)或(huo)支架結構上(shang)的(de)作用(yong)(yong)力。