補償器(qi)(qi)習慣上(shang)也(ye)叫(jiao)膨脹節(jie)，或(huo)伸縮節(jie)。由構成其(qi)工作主體的(de)(de)波紋管(guan)(guan)(guan)(guan)(guan)（一種彈性元(yuan)件(jian)）和端管(guan)(guan)(guan)(guan)(guan)、支架(jia)、法蘭、導管(guan)(guan)(guan)(guan)(guan)等(deng)附件(jian)組成。 屬于(yu)一種補償元(yuan)件(jian)。利用其(qi)工作主體波紋管(guan)(guan)(guan)(guan)(guan)的(de)(de)有(you)效伸縮變(bian)形，以吸收(shou)管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等(deng)由熱脹冷縮等(deng)原因而產生的(de)(de)尺寸變(bian)化，或(huo)補償管(guan)(guan)(guan)(guan)(guan)線、導管(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等(deng)的(de)(de)軸向、橫向和角向位移(yi)。也(ye)可用于(yu)降噪減振(zhen)。在現代工業中(zhong)用途(tu)廣(guang)泛。供(gong)熱上(shang)，為了防止供(gong)熱管(guan)(guan)(guan)(guan)(guan)道升溫時，由于(yu)熱伸長或(huo)溫度應(ying)力而引起管(guan)(guan)(guan)(guan)(guan)道變(bian)形或(huo)破壞，需要在管(guan)(guan)(guan)(guan)(guan)道上(shang)設置補償器(qi)(qi)，以補償管(guan)(guan)(guan)(guan)(guan)道的(de)(de)熱伸長，從(cong)而減小管(guan)(guan)(guan)(guan)(guan)壁的(de)(de)應(ying)力和作用在閥件(jian)或(huo)支架(jia)結構上(shang)的(de)(de)作用力。