補償器(qi)習(xi)慣上(shang)也叫膨脹節，或(huo)伸(shen)縮(suo)節。由構(gou)成(cheng)其(qi)工作(zuo)主體(ti)的(de)(de)波紋(wen)管(guan)(guan)(guan)(guan)(guan)（一種彈性元(yuan)件(jian)）和(he)端管(guan)(guan)(guan)(guan)(guan)、支(zhi)(zhi)架(jia)、法蘭、導管(guan)(guan)(guan)(guan)(guan)等附(fu)件(jian)組成(cheng)。 屬于(yu)一種補償元(yuan)件(jian)。利用(yong)(yong)(yong)其(qi)工作(zuo)主體(ti)波紋(wen)管(guan)(guan)(guan)(guan)(guan)的(de)(de)有(you)效伸(shen)縮(suo)變形(xing)，以(yi)吸收管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)等由熱(re)(re)脹冷(leng)縮(suo)等原因而產(chan)生的(de)(de)尺寸變化，或(huo)補償管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)等的(de)(de)軸向、橫(heng)向和(he)角向位(wei)移。也可用(yong)(yong)(yong)于(yu)降噪(zao)減(jian)振。在現(xian)代(dai)工業中用(yong)(yong)(yong)途廣泛(fan)。供熱(re)(re)上(shang)，為了防止供熱(re)(re)管(guan)(guan)(guan)(guan)(guan)道(dao)升溫時，由于(yu)熱(re)(re)伸(shen)長或(huo)溫度應力而引起管(guan)(guan)(guan)(guan)(guan)道(dao)變形(xing)或(huo)破壞，需要在管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)設置(zhi)補償器(qi)，以(yi)補償管(guan)(guan)(guan)(guan)(guan)道(dao)的(de)(de)熱(re)(re)伸(shen)長，從而減(jian)小管(guan)(guan)(guan)(guan)(guan)壁的(de)(de)應力和(he)作(zuo)用(yong)(yong)(yong)在閥件(jian)或(huo)支(zhi)(zhi)架(jia)結構(gou)上(shang)的(de)(de)作(zuo)用(yong)(yong)(yong)力。