補(bu)(bu)(bu)(bu)償(chang)器(qi)(qi)習慣上(shang)(shang)也(ye)叫膨脹節，或(huo)伸(shen)(shen)縮(suo)節。由(you)構(gou)成(cheng)其工(gong)作(zuo)(zuo)主體的波紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)（一(yi)(yi)種(zhong)彈性元件）和端管(guan)(guan)(guan)(guan)(guan)、支(zhi)架(jia)、法(fa)蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)等(deng)附(fu)件組成(cheng)。 屬于(yu)一(yi)(yi)種(zhong)補(bu)(bu)(bu)(bu)償(chang)元件。利用(yong)其工(gong)作(zuo)(zuo)主體波紋(wen)(wen)管(guan)(guan)(guan)(guan)(guan)的有效伸(shen)(shen)縮(suo)變(bian)形，以吸(xi)收(shou)管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由(you)熱脹冷縮(suo)等(deng)原因而產生(sheng)的尺(chi)寸(cun)變(bian)化，或(huo)補(bu)(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的軸向、橫向和角向位移。也(ye)可用(yong)于(yu)降(jiang)噪減振(zhen)。在(zai)現代(dai)工(gong)業(ye)中用(yong)途廣泛(fan)。供熱上(shang)(shang)，為了(le)防止供熱管(guan)(guan)(guan)(guan)(guan)道升溫時，由(you)于(yu)熱伸(shen)(shen)長或(huo)溫度應力(li)而引起管(guan)(guan)(guan)(guan)(guan)道變(bian)形或(huo)破壞，需要在(zai)管(guan)(guan)(guan)(guan)(guan)道上(shang)(shang)設置補(bu)(bu)(bu)(bu)償(chang)器(qi)(qi)，以補(bu)(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)道的熱伸(shen)(shen)長，從而減小管(guan)(guan)(guan)(guan)(guan)壁的應力(li)和作(zuo)(zuo)用(yong)在(zai)閥件或(huo)支(zhi)架(jia)結構(gou)上(shang)(shang)的作(zuo)(zuo)用(yong)力(li)。