補償器習慣上也叫膨(peng)脹(zhang)節，或(huo)伸縮(suo)節。由(you)構(gou)成其(qi)工作主體的(de)波紋(wen)管(guan)(guan)(guan)(guan)(guan)（一種彈性元件(jian)）和端管(guan)(guan)(guan)(guan)(guan)、支架、法(fa)蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)等(deng)附件(jian)組成。 屬(shu)于一種補償元件(jian)。利(li)用(yong)(yong)其(qi)工作主體波紋(wen)管(guan)(guan)(guan)(guan)(guan)的(de)有效伸縮(suo)變形(xing)，以吸(xi)收(shou)管(guan)(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器等(deng)由(you)熱脹(zhang)冷(leng)縮(suo)等(deng)原因而產(chan)生(sheng)的(de)尺寸變化，或(huo)補償管(guan)(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器等(deng)的(de)軸向(xiang)、橫向(xiang)和角向(xiang)位(wei)移。也可用(yong)(yong)于降噪減振。在現(xian)代工業中用(yong)(yong)途廣泛。供熱上，為了(le)防止供熱管(guan)(guan)(guan)(guan)(guan)道(dao)升溫時，由(you)于熱伸長或(huo)溫度應力而引起管(guan)(guan)(guan)(guan)(guan)道(dao)變形(xing)或(huo)破壞，需(xu)要在管(guan)(guan)(guan)(guan)(guan)道(dao)上設置補償器，以補償管(guan)(guan)(guan)(guan)(guan)道(dao)的(de)熱伸長，從而減小管(guan)(guan)(guan)(guan)(guan)壁的(de)應力和作用(yong)(yong)在閥件(jian)或(huo)支架結構(gou)上的(de)作用(yong)(yong)力。