補償器(qi)(qi)習慣上(shang)也叫膨脹節，或(huo)伸縮節。由構成其(qi)工(gong)作(zuo)主體(ti)(ti)的波(bo)紋(wen)(wen)管(guan)(guan)(guan)(guan)（一種(zhong)彈性(xing)元件）和端管(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導(dao)管(guan)(guan)(guan)(guan)等(deng)附件組(zu)成。 屬(shu)于(yu)(yu)一種(zhong)補償元件。利用其(qi)工(gong)作(zuo)主體(ti)(ti)波(bo)紋(wen)(wen)管(guan)(guan)(guan)(guan)的有效伸縮變形，以吸收管(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)由熱(re)(re)脹冷縮等(deng)原因而產生的尺寸變化(hua)，或(huo)補償管(guan)(guan)(guan)(guan)線(xian)、導(dao)管(guan)(guan)(guan)(guan)、容器(qi)(qi)等(deng)的軸向(xiang)(xiang)、橫向(xiang)(xiang)和角向(xiang)(xiang)位移(yi)。也可用于(yu)(yu)降噪減(jian)振。在(zai)現代工(gong)業中用途(tu)廣(guang)泛(fan)。供熱(re)(re)上(shang)，為了防止供熱(re)(re)管(guan)(guan)(guan)(guan)道升溫時，由于(yu)(yu)熱(re)(re)伸長或(huo)溫度(du)應力而引起管(guan)(guan)(guan)(guan)道變形或(huo)破壞，需要在(zai)管(guan)(guan)(guan)(guan)道上(shang)設置補償器(qi)(qi)，以補償管(guan)(guan)(guan)(guan)道的熱(re)(re)伸長，從而減(jian)小管(guan)(guan)(guan)(guan)壁(bi)的應力和作(zuo)用在(zai)閥件或(huo)支(zhi)架結構上(shang)的作(zuo)用力。