補(bu)(bu)償器(qi)(qi)習慣上也叫(jiao)膨脹節，或伸縮節。由構(gou)成(cheng)其工作主體的(de)(de)波紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)（一種(zhong)彈性元(yuan)件(jian)）和端(duan)管(guan)(guan)(guan)(guan)(guan)(guan)、支(zhi)架、法蘭、導(dao)管(guan)(guan)(guan)(guan)(guan)(guan)等附件(jian)組成(cheng)。 屬于(yu)一種(zhong)補(bu)(bu)償元(yuan)件(jian)。利用其工作主體波紋(wen)管(guan)(guan)(guan)(guan)(guan)(guan)的(de)(de)有效伸縮變形，以(yi)吸收管(guan)(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等由熱脹冷縮等原因而產生的(de)(de)尺(chi)寸變化，或補(bu)(bu)償管(guan)(guan)(guan)(guan)(guan)(guan)線、導(dao)管(guan)(guan)(guan)(guan)(guan)(guan)、容(rong)器(qi)(qi)等的(de)(de)軸(zhou)向、橫向和角(jiao)向位移(yi)。也可用于(yu)降噪減(jian)振(zhen)。在(zai)現代工業中用途廣泛。供熱上，為了防(fang)止供熱管(guan)(guan)(guan)(guan)(guan)(guan)道升溫(wen)時，由于(yu)熱伸長或溫(wen)度應力而引起管(guan)(guan)(guan)(guan)(guan)(guan)道變形或破壞(huai)，需要在(zai)管(guan)(guan)(guan)(guan)(guan)(guan)道上設置補(bu)(bu)償器(qi)(qi)，以(yi)補(bu)(bu)償管(guan)(guan)(guan)(guan)(guan)(guan)道的(de)(de)熱伸長，從而減(jian)小管(guan)(guan)(guan)(guan)(guan)(guan)壁的(de)(de)應力和作用在(zai)閥(fa)件(jian)或支(zhi)架結構(gou)上的(de)(de)作用力。