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)一種(zhong)補(bu)償(chang)元(yuan)件。利用(yong)其工作主體波(bo)紋管(guan)(guan)(guan)(guan)(guan)的(de)有效伸(shen)縮(suo)變(bian)形，以(yi)吸(xi)收管(guan)(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)等由(you)熱脹冷縮(suo)等原(yuan)因而產生的(de)尺(chi)寸(cun)變(bian)化，或(huo)(huo)補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)等的(de)軸(zhou)向、橫向和角向位(wei)移。也(ye)可(ke)用(yong)于(yu)降噪減振。在現代(dai)工業中用(yong)途廣泛。供熱上，為(wei)了防止(zhi)供熱管(guan)(guan)(guan)(guan)(guan)道升溫(wen)時，由(you)于(yu)熱伸(shen)長或(huo)(huo)溫(wen)度應力而引起管(guan)(guan)(guan)(guan)(guan)道變(bian)形或(huo)(huo)破壞，需要(yao)在管(guan)(guan)(guan)(guan)(guan)道上設(she)置補(bu)償(chang)器(qi)，以(yi)補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)道的(de)熱伸(shen)長，從而減小(xiao)管(guan)(guan)(guan)(guan)(guan)壁(bi)的(de)應力和作用(yong)在閥(fa)件或(huo)(huo)支(zhi)架結構上的(de)作用(yong)力。