Generally, the screen surface adopts a variety of layout methods with different inclination angles. There is a large inclination angle screen surface at the feeding end, which can make more materials pass through with higher moving speed and thinner material stratification.
This earlier stratification allows the finer particles to approach the screen surface more quickly and pass through the screen openings relatively unimpeded, as the bulk material moves faster through the steep slope.
With the decrease of the inclination of the screen surface and the gradual reduction of the material on the screen surface of the wire mesh vibrating screen due to the sieving, the moving speed of the material decreases, and the same material thickness can be maintained on the screen surface, making the material easy to turn over and loose.
The particles near the sieve gap size have more opportunities to pass through the sieve holes and improve the sieving efficiency. It can be seen that there are three main factors affecting the sieving, the width, length and number of segments of the sieve surface.
Old-fashioned metal screens are mostly steel woven screens, which also have their advantages, such as large weight and high opening rate. Because of certain elasticity in the screening process, they can be vibrated at high frequency to reduce material adhesion and improve screening efficiency.
However, when the processing capacity increases, the service life of this type of metal screen is short, and many of them will be damaged in two or three days, and must be replaced in seven days, which increases the difficulty of repair and affects the processing capacity of the ball mill.
When it comes to polyurethane vibrating screens, our first impression is often square-hole polyurethane screens with larger screen holes. For mine precision screens, it is a metal screen with a relatively high opening rate, or a nylon screen with better elasticity. network.
In fact, because of its excellent characteristics, polyurethane precision mesh has been gradually accepted by people, and it has a great potential to replace it.
Mine polyurethane screen is mainly used in mining, coal, petroleum, environmental protection and other industries. It has a wide range of applications. Where are the main advantages?
1. The mine screen has excellent bearing capacity, impact resistance, shock absorption function, and excellent cold resistance. It still maintains good elasticity, gentleness and other functions at minus 35 °C, wear resistance, corrosion resistance, acid and alkali resistance, oil resistance, water resistance, Anti-mildew and anti-bacterial, anti-aging.
2. Beautiful appearance, optional colors, light weight, simple installation method, low noise, etc., which greatly reduces labor intensity and improves working environment.
3. The superior physical function has both toughness and rigidity to ensure that the size of the screen gap of the polyurethane screen is stable during use.
To maximize the stability of the particle size under the sieve, it is not easy to block holes. Advanced precision mold technology is used to ensure high opening rate and high screening power to the greatest extent.
Polyurethane screen has large size, good elasticity, wear resistance, light weight, long life, no need to splicing during use, low labor intensity, and low operating noise. There are three kinds of commonly used polyurethane mine precision screens.
The first type of polyurethane precision sieve mesh, the short side of the sieve is 0.1mm~0.3mm, the long side is 15mm~18mm, the opening rate is more than 25%, and it has high screening power, but the length of the screen hole is too large, and it is easy to form a relatively small screen. Particles with large particle size pass through the sieve, which affects the sieving quality.
The second type of polyurethane screen uses polyurethane-coated steel bars or steel wires to improve the strength, sacrificing the flexibility of the polyurethane screen, increasing the quality of this kind of china wire mesh screens and the cross-sectional area of the screen separator, and the opening rate is low.
The third type of polyurethane precision screen mesh has a rectangular mesh and is surrounded by vertical and horizontal polyurethane mesh screens. The mesh width is 0.25mm to 3mm, the length is about 25mm, and the thickness is 3mm.
The screen is reinforced with aramid fiber, the diameter of the reinforcing fiber is 0.5mm, and the overall size of the screen is up to 1200mm×1600m.
With these three kinds of polyurethane screens, not only the defects of metal screens and nylon screens are dealt with, but also many other incomparable advantages are added, so it is natural that the utilization rate of polyurethane screens is getting higher and higher.