補(bu)(bu)償(chang)(chang)器(qi)習慣上(shang)也叫(jiao)膨脹節，或(huo)伸(shen)縮節。由(you)構(gou)成其工(gong)作(zuo)(zuo)主體(ti)的波(bo)(bo)紋管(guan)(guan)(guan)(guan)(guan)（一(yi)種(zhong)彈性元(yuan)(yuan)件(jian)）和(he)端(duan)管(guan)(guan)(guan)(guan)(guan)、支(zhi)(zhi)架、法蘭、導管(guan)(guan)(guan)(guan)(guan)等(deng)附件(jian)組(zu)成。 屬于一(yi)種(zhong)補(bu)(bu)償(chang)(chang)元(yuan)(yuan)件(jian)。利用(yong)其工(gong)作(zuo)(zuo)主體(ti)波(bo)(bo)紋管(guan)(guan)(guan)(guan)(guan)的有效伸(shen)縮變形(xing)，以吸收管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)由(you)熱(re)(re)脹冷縮等(deng)原因而(er)(er)產生的尺寸變化，或(huo)補(bu)(bu)償(chang)(chang)管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容器(qi)等(deng)的軸(zhou)向、橫向和(he)角向位(wei)移。也可用(yong)于降噪減(jian)振。在現代工(gong)業中用(yong)途(tu)廣泛。供(gong)熱(re)(re)上(shang)，為(wei)了防止供(gong)熱(re)(re)管(guan)(guan)(guan)(guan)(guan)道(dao)升(sheng)溫時，由(you)于熱(re)(re)伸(shen)長或(huo)溫度應力(li)而(er)(er)引起(qi)管(guan)(guan)(guan)(guan)(guan)道(dao)變形(xing)或(huo)破壞，需要在管(guan)(guan)(guan)(guan)(guan)道(dao)上(shang)設置補(bu)(bu)償(chang)(chang)器(qi)，以補(bu)(bu)償(chang)(chang)管(guan)(guan)(guan)(guan)(guan)道(dao)的熱(re)(re)伸(shen)長，從而(er)(er)減(jian)小管(guan)(guan)(guan)(guan)(guan)壁的應力(li)和(he)作(zuo)(zuo)用(yong)在閥件(jian)或(huo)支(zhi)(zhi)架結構(gou)上(shang)的作(zuo)(zuo)用(yong)力(li)。