補(bu)償(chang)器(qi)(qi)習慣上也叫膨脹(zhang)節(jie)，或(huo)(huo)伸(shen)縮節(jie)。由(you)(you)構成其工(gong)(gong)(gong)作(zuo)主(zhu)(zhu)體的(de)(de)波紋管（一種彈性元(yuan)件(jian)(jian)）和端(duan)管、支架、法蘭、導管等附件(jian)(jian)組成。 屬于(yu)一種補(bu)償(chang)元(yuan)件(jian)(jian)。利(li)用(yong)(yong)(yong)其工(gong)(gong)(gong)作(zuo)主(zhu)(zhu)體波紋管的(de)(de)有效伸(shen)縮變(bian)(bian)形(xing)，以吸(xi)收(shou)管線、導管、容器(qi)(qi)等由(you)(you)熱(re)(re)脹(zhang)冷縮等原因(yin)而產生的(de)(de)尺寸變(bian)(bian)化，或(huo)(huo)補(bu)償(chang)管線、導管、容器(qi)(qi)等的(de)(de)軸(zhou)向(xiang)、橫向(xiang)和角向(xiang)位移(yi)。也可(ke)用(yong)(yong)(yong)于(yu)降噪減振(zhen)。在(zai)(zai)現代工(gong)(gong)(gong)業中用(yong)(yong)(yong)途廣(guang)泛。供熱(re)(re)上，為(wei)了防止供熱(re)(re)管道升溫時，由(you)(you)于(yu)熱(re)(re)伸(shen)長或(huo)(huo)溫度(du)應力(li)而引起管道變(bian)(bian)形(xing)或(huo)(huo)破壞(huai)，需要在(zai)(zai)管道上設置(zhi)補(bu)償(chang)器(qi)(qi)，以補(bu)償(chang)管道的(de)(de)熱(re)(re)伸(shen)長，從(cong)而減小管壁的(de)(de)應力(li)和作(zuo)用(yong)(yong)(yong)在(zai)(zai)閥件(jian)(jian)或(huo)(huo)支架結構上的(de)(de)作(zuo)用(yong)(yong)(yong)力(li)。