補償(chang)(chang)(chang)器(qi)習慣上(shang)(shang)也叫膨脹節，或(huo)伸(shen)(shen)縮(suo)節。由(you)構(gou)成其(qi)工(gong)作主體(ti)的(de)(de)波(bo)紋管(guan)(guan)(guan)（一(yi)種彈性元(yuan)(yuan)件）和(he)(he)端管(guan)(guan)(guan)、支架(jia)、法(fa)蘭、導(dao)管(guan)(guan)(guan)等(deng)附(fu)件組成。 屬于(yu)一(yi)種補償(chang)(chang)(chang)元(yuan)(yuan)件。利用(yong)(yong)其(qi)工(gong)作主體(ti)波(bo)紋管(guan)(guan)(guan)的(de)(de)有效伸(shen)(shen)縮(suo)變(bian)形(xing)，以吸(xi)收(shou)管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)(rong)器(qi)等(deng)由(you)熱(re)(re)脹冷縮(suo)等(deng)原因而(er)產生的(de)(de)尺寸變(bian)化，或(huo)補償(chang)(chang)(chang)管(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)、容(rong)(rong)器(qi)等(deng)的(de)(de)軸(zhou)向、橫向和(he)(he)角向位(wei)移(yi)。也可用(yong)(yong)于(yu)降(jiang)噪(zao)減(jian)振(zhen)。在現代工(gong)業中(zhong)用(yong)(yong)途廣泛。供熱(re)(re)上(shang)(shang)，為了防止供熱(re)(re)管(guan)(guan)(guan)道(dao)升(sheng)溫(wen)時，由(you)于(yu)熱(re)(re)伸(shen)(shen)長(chang)或(huo)溫(wen)度應(ying)力而(er)引(yin)起管(guan)(guan)(guan)道(dao)變(bian)形(xing)或(huo)破(po)壞，需要在管(guan)(guan)(guan)道(dao)上(shang)(shang)設置補償(chang)(chang)(chang)器(qi)，以補償(chang)(chang)(chang)管(guan)(guan)(guan)道(dao)的(de)(de)熱(re)(re)伸(shen)(shen)長(chang)，從(cong)而(er)減(jian)小管(guan)(guan)(guan)壁(bi)的(de)(de)應(ying)力和(he)(he)作用(yong)(yong)在閥件或(huo)支架(jia)結構(gou)上(shang)(shang)的(de)(de)作用(yong)(yong)力。