The requirements and application environment of various kinds of material roller in coal mine
Through many years of research, we have carried out a detailed analysis and summary of the application of the roller in the coal mine:
1, water and mud on the roller bearing pollution, resulting in increased bearing resistance until the card failure.
2, water and water sulfur and acid corrosion of the pipe body corrosion. The 4.5 mm thick wall is usually corroded for a year or so, and is particularly severe for as long as 5 months.
3, the heart of the heart of the stent device to adjust the heart roller, and the tape is not 90 degrees straight, but the use of lateral conflict force to force the tape to avoid deviation, roller tube wall will wear quickly, with a belt of wear is also very serious. The wall of the supporting roller on the forward support is relatively fast.
4, tapered roller, tube wall is also simply wear.
5, the buffer roller life of about 3 months. Therefore, the use of coal mine roller is not only the need for a good seal, the bearing can work for a long time under the conditions of good smoothness, and the roller tube wall is necessary to wear, corrosion resistance, in order to obtain the desired role.
The general principle of roller design: simple structure, flexible rotation, low cost, durable.
The design principle of roll body
1, selection principle: applicable, convenient. Roller body material of a wide range of steel, plastics, ceramics, cast stone, composite materials etc.. According to the actual working conditions of the roller, in line with the principles of economy and convenience. In particular, the bearing seat of the ceramic roller should be handled well, otherwise the roller is too big.
2, design, processing principle: roll surface of the round, the two true bearing seat of the concentricity of the installation in line with national standards, to pay attention to the roller body static balance, in the static state to stop in any position.
3, can batch, qualified production.
Two, the axis of the design principles: according to the market supply, the use of Q235 cold drawn round, tolerance criteria for H6 (no need to use js6 or K6). Hot rolled bar. The short axis must use biparietal needle processing (long axis can only use the U-turn car), H6 (the standard is not necessary to use js6 or K6).
Roller shaft (sealing bearing) the actual operating temperature should be lower than the drop point 10-20 C. The use of synthetic grease should be lower than the temperature of 20-30.
This is due to the sealed bearings in accordance with the working temperature of the choice of grease, the main indicators should be drop point, oxidation stability and low temperature performance, drop point can generally be used to evaluate the high temperature performance.
Roller bearing load select grease, grease for heavy load should be selected penetration small. In the high pressure work in addition to the needle penetration is small, but also have a higher oil film strength and extreme pressure performance. According to the environmental conditions to choose the grease, calcium based grease is not easy to dissolve in water, suitable for dry and less moisture environment. |
