補償器(qi)(qi)習慣上也叫膨脹節，或(huo)伸(shen)縮(suo)(suo)節。由構成其工作主(zhu)體(ti)的(de)(de)波紋(wen)管(guan)(guan)(guan)(guan)(guan)（一種彈性元件(jian)）和端(duan)管(guan)(guan)(guan)(guan)(guan)、支架(jia)、法蘭、導管(guan)(guan)(guan)(guan)(guan)等(deng)附件(jian)組成。 屬(shu)于一種補償元件(jian)。利用(yong)(yong)其工作主(zhu)體(ti)波紋(wen)管(guan)(guan)(guan)(guan)(guan)的(de)(de)有效(xiao)伸(shen)縮(suo)(suo)變(bian)形，以吸收管(guan)(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由熱(re)(re)脹冷縮(suo)(suo)等(deng)原因而產生的(de)(de)尺寸變(bian)化，或(huo)補償管(guan)(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的(de)(de)軸(zhou)向、橫向和角向位移。也可用(yong)(yong)于降(jiang)噪減(jian)振。在現代工業中用(yong)(yong)途(tu)廣泛(fan)。供(gong)熱(re)(re)上，為了防止供(gong)熱(re)(re)管(guan)(guan)(guan)(guan)(guan)道升(sheng)溫時，由于熱(re)(re)伸(shen)長或(huo)溫度(du)應(ying)(ying)力(li)而引起管(guan)(guan)(guan)(guan)(guan)道變(bian)形或(huo)破壞，需要在管(guan)(guan)(guan)(guan)(guan)道上設置補償器(qi)(qi)，以補償管(guan)(guan)(guan)(guan)(guan)道的(de)(de)熱(re)(re)伸(shen)長，從(cong)而減(jian)小管(guan)(guan)(guan)(guan)(guan)壁(bi)的(de)(de)應(ying)(ying)力(li)和作用(yong)(yong)在閥件(jian)或(huo)支架(jia)結構上的(de)(de)作用(yong)(yong)力(li)。