補(bu)償(chang)器習(xi)慣上也(ye)(ye)叫膨脹節，或伸縮節。由(you)構(gou)成(cheng)(cheng)其工作主體的(de)(de)(de)波(bo)紋管(guan)(guan)(guan)(guan)（一(yi)種彈(dan)性元件(jian)）和端管(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導(dao)管(guan)(guan)(guan)(guan)等附(fu)件(jian)組成(cheng)(cheng)。 屬于一(yi)種補(bu)償(chang)元件(jian)。利用(yong)其工作主體波(bo)紋管(guan)(guan)(guan)(guan)的(de)(de)(de)有效(xiao)伸縮變形，以吸收管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容器等由(you)熱(re)(re)脹冷縮等原(yuan)因而(er)(er)產生的(de)(de)(de)尺(chi)寸變化，或補(bu)償(chang)管(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)、容器等的(de)(de)(de)軸向(xiang)、橫向(xiang)和角向(xiang)位移。也(ye)(ye)可用(yong)于降噪減(jian)振。在(zai)現代工業中用(yong)途廣泛。供熱(re)(re)上，為了防止供熱(re)(re)管(guan)(guan)(guan)(guan)道升溫時，由(you)于熱(re)(re)伸長或溫度應(ying)力而(er)(er)引起(qi)管(guan)(guan)(guan)(guan)道變形或破壞，需要在(zai)管(guan)(guan)(guan)(guan)道上設置補(bu)償(chang)器，以補(bu)償(chang)管(guan)(guan)(guan)(guan)道的(de)(de)(de)熱(re)(re)伸長，從(cong)而(er)(er)減(jian)小管(guan)(guan)(guan)(guan)壁的(de)(de)(de)應(ying)力和作用(yong)在(zai)閥件(jian)或支(zhi)架結構(gou)上的(de)(de)(de)作用(yong)力。