補償器習慣上也叫膨脹節，或伸縮節。由構成其工作主體的波紋管（一種彈性元件）和端管、支架、法蘭、導管等附件組成。膨脹節廠家 屬于(yu)(yu)一種補(bu)(bu)償(chang)(chang)元件(jian)。利用(yong)(yong)其(qi)工(gong)作(zuo)主(zhu)體(ti)波紋(wen)管(guan)(guan)(guan)(guan)的(de)(de)有效伸(shen)縮變(bian)形(xing)，以吸收管(guan)(guan)(guan)(guan)線(xian)(xian)、導管(guan)(guan)(guan)(guan)、容器(qi)等(deng)(deng)由熱(re)脹冷縮等(deng)(deng)原(yuan)因(yin)而(er)(er)產生的(de)(de)尺寸變(bian)化，或(huo)補(bu)(bu)償(chang)(chang)管(guan)(guan)(guan)(guan)線(xian)(xian)、導管(guan)(guan)(guan)(guan)、容器(qi)等(deng)(deng)的(de)(de)軸(zhou)向(xiang)、橫向(xiang)和角向(xiang)位移(yi)。也可用(yong)(yong)于(yu)(yu)降噪(zao)減振。在現代工(gong)業中用(yong)(yong)途廣泛。供(gong)(gong)熱(re)上(shang)，為了(le)防止供(gong)(gong)熱(re)管(guan)(guan)(guan)(guan)道(dao)升(sheng)溫時，由于(yu)(yu)熱(re)伸(shen)長(chang)或(huo)溫度應力(li)而(er)(er)引起管(guan)(guan)(guan)(guan)道(dao)變(bian)形(xing)或(huo)破(po)壞，需要(yao)在管(guan)(guan)(guan)(guan)道(dao)上(shang)設置(zhi)補(bu)(bu)償(chang)(chang)器(qi)，以補(bu)(bu)償(chang)(chang)管(guan)(guan)(guan)(guan)道(dao)的(de)(de)熱(re)伸(shen)長(chang)，從(cong)而(er)(er)減小管(guan)(guan)(guan)(guan)壁的(de)(de)應力(li)和作(zuo)用(yong)(yong)在閥件(jian)或(huo)支架結構上(shang)的(de)(de)作(zuo)用(yong)(yong)力(li)。