欧美国产精品专区,丝袜亚洲欧美日韩综合,秋霞在线午夜,亚洲综合激情网

From May 10 to November 11, the Chinese Academy of Sciences held a meeting of experts in the development of the Institute of Instrument Research, and more than 20 instrument development experts attended the meeting. The conference mainly ...

How to connect the entire valve and pipeline or equipment, this problem can not be ignored, because the valve running, running, drip, leakage phenomenon, the vast majority occurred here.

The principle of maintenance during the operation of the valve is as follows: 1 Keep the outside of the valve and the active part clean and protect the integrity of the valve paint. The surface of the valve, trapezoidal threads on the stem ...

Taboo 1: the main materials, equipment and products used in construction, and lack of technical quality identification documents or product qualification certificates conforming to the current standards issued by the state or department...

At present, the butterfly valve, as a component used to realize on-off and flow control of pipeline system, has been widely used in many fields such as petroleum, chemical industry, metallurgy, hydropower and so on. In the ...

At the same time with dynamic balance and electric adjustment of two functions, and two functions simultaneously. The dynamic balancing electric regulating valve is installed on the return pipe of the combination air conditioner ...