補(bu)償(chang)器(qi)(qi)習慣(guan)上(shang)(shang)也叫(jiao)膨脹節，或(huo)(huo)伸縮節。由(you)(you)構成其(qi)工作主體(ti)的波(bo)紋(wen)管(guan)(guan)(guan)(guan)(guan)（一種(zhong)(zhong)彈性元(yuan)件(jian)）和端管(guan)(guan)(guan)(guan)(guan)、支架、法蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)等(deng)附件(jian)組成。 屬于一種(zhong)(zhong)補(bu)償(chang)元(yuan)件(jian)。利用(yong)其(qi)工作主體(ti)波(bo)紋(wen)管(guan)(guan)(guan)(guan)(guan)的有效伸縮變(bian)(bian)(bian)形，以吸收管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由(you)(you)熱(re)(re)脹冷縮等(deng)原(yuan)因而(er)產生的尺寸(cun)變(bian)(bian)(bian)化，或(huo)(huo)補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的軸向、橫(heng)向和角向位移(yi)。也可用(yong)于降噪減(jian)振。在現(xian)代工業中用(yong)途廣泛。供熱(re)(re)上(shang)(shang)，為了防止供熱(re)(re)管(guan)(guan)(guan)(guan)(guan)道(dao)升(sheng)溫(wen)時(shi)，由(you)(you)于熱(re)(re)伸長或(huo)(huo)溫(wen)度應力(li)(li)而(er)引起管(guan)(guan)(guan)(guan)(guan)道(dao)變(bian)(bian)(bian)形或(huo)(huo)破壞，需要在管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)(shang)設置補(bu)償(chang)器(qi)(qi)，以補(bu)償(chang)管(guan)(guan)(guan)(guan)(guan)道(dao)的熱(re)(re)伸長，從而(er)減(jian)小管(guan)(guan)(guan)(guan)(guan)壁的應力(li)(li)和作用(yong)在閥件(jian)或(huo)(huo)支架結構上(shang)(shang)的作用(yong)力(li)(li)。