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)償元件。利(li)用(yong)其工(gong)作(zuo)(zuo)主體波紋管(guan)(guan)(guan)(guan)的有效伸縮(suo)變(bian)形，以(yi)吸收管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等(deng)由熱脹冷縮(suo)等(deng)原(yuan)因而產(chan)生(sheng)的尺寸變(bian)化，或(huo)補(bu)償管(guan)(guan)(guan)(guan)線(xian)、導管(guan)(guan)(guan)(guan)、容(rong)器(qi)等(deng)的軸向(xiang)、橫(heng)向(xiang)和角向(xiang)位(wei)移。也可用(yong)于(yu)(yu)降噪減振。在(zai)(zai)現代(dai)工(gong)業(ye)中用(yong)途(tu)廣泛。供熱上，為了防(fang)止(zhi)供熱管(guan)(guan)(guan)(guan)道(dao)升溫時，由于(yu)(yu)熱伸長或(huo)溫度應(ying)力而引起(qi)管(guan)(guan)(guan)(guan)道(dao)變(bian)形或(huo)破壞，需要在(zai)(zai)管(guan)(guan)(guan)(guan)道(dao)上設置補(bu)償器(qi)，以(yi)補(bu)償管(guan)(guan)(guan)(guan)道(dao)的熱伸長，從而減小管(guan)(guan)(guan)(guan)壁的應(ying)力和作(zuo)(zuo)用(yong)在(zai)(zai)閥件或(huo)支(zhi)架結構上的作(zuo)(zuo)用(yong)力。