補(bu)(bu)(bu)償(chang)器習慣上也叫膨脹(zhang)節，或(huo)伸(shen)(shen)縮節。由(you)(you)構(gou)成其工(gong)(gong)(gong)作(zuo)主(zhu)體的(de)波(bo)紋管(guan)(guan)(guan)（一(yi)(yi)種(zhong)彈性元(yuan)件(jian)(jian)）和(he)(he)端管(guan)(guan)(guan)、支架、法蘭、導管(guan)(guan)(guan)等附(fu)件(jian)(jian)組成。 屬于(yu)(yu)一(yi)(yi)種(zhong)補(bu)(bu)(bu)償(chang)元(yuan)件(jian)(jian)。利用(yong)其工(gong)(gong)(gong)作(zuo)主(zhu)體波(bo)紋管(guan)(guan)(guan)的(de)有(you)效伸(shen)(shen)縮變(bian)形(xing)，以吸(xi)收管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器等由(you)(you)熱脹(zhang)冷縮等原因而(er)產(chan)生(sheng)的(de)尺寸變(bian)化，或(huo)補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)線、導管(guan)(guan)(guan)、容(rong)器等的(de)軸向(xiang)、橫(heng)向(xiang)和(he)(he)角向(xiang)位移(yi)。也可用(yong)于(yu)(yu)降(jiang)噪(zao)減(jian)振。在現代工(gong)(gong)(gong)業中用(yong)途廣(guang)泛(fan)。供(gong)熱上，為了防止供(gong)熱管(guan)(guan)(guan)道(dao)升溫(wen)時，由(you)(you)于(yu)(yu)熱伸(shen)(shen)長或(huo)溫(wen)度應力(li)而(er)引起管(guan)(guan)(guan)道(dao)變(bian)形(xing)或(huo)破(po)壞，需要在管(guan)(guan)(guan)道(dao)上設置補(bu)(bu)(bu)償(chang)器，以補(bu)(bu)(bu)償(chang)管(guan)(guan)(guan)道(dao)的(de)熱伸(shen)(shen)長，從而(er)減(jian)小管(guan)(guan)(guan)壁(bi)的(de)應力(li)和(he)(he)作(zuo)用(yong)在閥件(jian)(jian)或(huo)支架結(jie)構(gou)上的(de)作(zuo)用(yong)力(li)。