Closing valve opening and closing pieces of plug-shaped flap, the sealing surface was flat or t.......

The Central Meteorological Observatory issued a national weather forecast at 17:00 yesterda.......

The 13th Shanghai International Machine Tool Show was held in Shanghai at the end of June. O.......

China Yizhong Group actively promotes scientific and technological research and development.......

One. The main structure of the reciprocating pump and the main working principle Working princi.......

How to choose a toilet is an old problem. Toilets are the basic b.......

The owner who started the renovation in May discovered that many building materials have b.......

Heat pump technology is a new type of energy-saving.......