補償(chang)器(qi)習慣上也(ye)叫(jiao)膨脹節(jie)，或(huo)(huo)伸(shen)縮(suo)節(jie)。由構成其工(gong)作(zuo)主體的(de)波(bo)紋管(guan)(guan)(guan)(guan)(guan)（一(yi)種彈性元件(jian)）和端管(guan)(guan)(guan)(guan)(guan)、支架、法蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)等(deng)(deng)附(fu)件(jian)組成。 屬于(yu)一(yi)種補償(chang)元件(jian)。利(li)用(yong)其工(gong)作(zuo)主體波(bo)紋管(guan)(guan)(guan)(guan)(guan)的(de)有(you)效(xiao)伸(shen)縮(suo)變(bian)(bian)形，以吸收管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)(deng)由熱(re)脹冷縮(suo)等(deng)(deng)原因而產生的(de)尺(chi)寸變(bian)(bian)化(hua)，或(huo)(huo)補償(chang)管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)(deng)的(de)軸(zhou)向、橫(heng)向和角向位移。也(ye)可用(yong)于(yu)降噪減(jian)振。在(zai)(zai)現代(dai)工(gong)業中用(yong)途(tu)廣泛(fan)。供(gong)熱(re)上，為了防止(zhi)供(gong)熱(re)管(guan)(guan)(guan)(guan)(guan)道(dao)升溫(wen)時(shi)，由于(yu)熱(re)伸(shen)長或(huo)(huo)溫(wen)度(du)應力(li)而引起管(guan)(guan)(guan)(guan)(guan)道(dao)變(bian)(bian)形或(huo)(huo)破壞，需(xu)要在(zai)(zai)管(guan)(guan)(guan)(guan)(guan)道(dao)上設(she)置補償(chang)器(qi)，以補償(chang)管(guan)(guan)(guan)(guan)(guan)道(dao)的(de)熱(re)伸(shen)長，從而減(jian)小管(guan)(guan)(guan)(guan)(guan)壁(bi)的(de)應力(li)和作(zuo)用(yong)在(zai)(zai)閥件(jian)或(huo)(huo)支架結(jie)構上的(de)作(zuo)用(yong)力(li)。