補償(chang)器(qi)習(xi)慣上(shang)(shang)也(ye)叫膨脹節，或(huo)伸縮節。由構成(cheng)(cheng)其工(gong)作(zuo)主體的波紋(wen)管(guan)(guan)(guan)（一(yi)種(zhong)彈性(xing)元件(jian)）和端(duan)管(guan)(guan)(guan)、支架(jia)、法(fa)蘭、導管(guan)(guan)(guan)等附件(jian)組成(cheng)(cheng)。 屬于一(yi)種(zhong)補償(chang)元件(jian)。利用(yong)其工(gong)作(zuo)主體波紋(wen)管(guan)(guan)(guan)的有效伸縮變(bian)形，以吸收管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器(qi)等由熱(re)脹冷(leng)縮等原(yuan)因而產生(sheng)的尺(chi)寸變(bian)化(hua)，或(huo)補償(chang)管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器(qi)等的軸(zhou)向、橫向和角向位(wei)移。也(ye)可用(yong)于降噪(zao)減振。在現代(dai)工(gong)業中用(yong)途廣(guang)泛(fan)。供(gong)熱(re)上(shang)(shang)，為了防止供(gong)熱(re)管(guan)(guan)(guan)道升溫(wen)時(shi)，由于熱(re)伸長或(huo)溫(wen)度(du)應力而引(yin)起(qi)管(guan)(guan)(guan)道變(bian)形或(huo)破壞，需要在管(guan)(guan)(guan)道上(shang)(shang)設置補償(chang)器(qi)，以補償(chang)管(guan)(guan)(guan)道的熱(re)伸長，從(cong)而減小管(guan)(guan)(guan)壁的應力和作(zuo)用(yong)在閥件(jian)或(huo)支架(jia)結(jie)構上(shang)(shang)的作(zuo)用(yong)力。