I. Introduction
1. Mineral properties and uses
Mica is a layered silicate mineral. The mica minerals include muscovite, biotite and scale mica. Commonly used in industry white spoon is muscovite, followed by phlogopite. The properties of mica minerals are shown in Table 1, and the use is shown in Table 2.
2. Resources and production
The distribution of mica resources in China is shown in Table 3, and the output is shown in Table 4. World mica production is shown in Table 5.
3. Product quality standards
There are currently no national standards for Chinese mica products, only two standards:
(1) Industrial raw material mica standard jc49-82
This standard is applicable to the processing of raw materials for electrical and telecommunication mica insulation materials. It is divided into five categories according to the largest effective area of ​​either side of the mica crystal. See Table 6. (2) Standard for mica film for electronic tubes jc52-82
This standard applies to high quality natural muscovite tablets. The diameter of the effective area is divided into ten specifications: Ñ„15, 17, 19, 21, 25, 30, 35, 40, 45, 50 mm. The percentage of the effective area to the total area should be in accordance with Table 7. The thickness, tolerance and thickness difference between any two points in the effective area shall be in accordance with Table 8.
The Y-type basic valve of Aone-Best is the basic mother valve of all hydraulic control valves. It can equiped with different pilot to adapt to different occasions from the function. For example, with a pressure reducing pilot, the whole valve is a pressure reducing valve; with a pressure relief pilot, the whole valve becomes a pressure relief valve, and so on. Valves are available in a variety of size and flange standards for selection, widely used in municipal water supply, building water supply, air conditioning, fire protection, industrial water, power and irrigation facilities.
Basic Valve,Y Type Control Valve,Y Type Pneumatic Valve,Y Type Pneumatic Control Valve
A1BEST International Corporation , https://www.aone-best.com