色8激情欧美成人久久综合电影,又粗又猛又黄又爽无遮挡,欧美亚洲日韩国产人成在线播放,欧美超大胆裸体xx视频

2021-07-05 09:58:05

See details

What is refractory brick? What is the use of refractory bricks?

2019-07-25 08:46:27

Refractory bricks are referred to as fire bricks, refractory materials fired from refractory clay or other refractory materials. Light yellow or brownish, mainly used in smelting furnaces, capable of withstanding high temperatures of 1,580 ° C - 1,770 ° C. Refractory bricks are generally divided into two types, namely, amorphous refractories and shaped refractories

See details