According to the requirement of coal particle size of power plant, circular vibrating scrceen is configured to screen the thermal coal of power plant. However, the working efficiency of inclined scrceen directly affects the efficient operation of power plant. Due to the selection and structural defects of the sieve plate, the screening rate of coal is very low, and the production of the sieve plate is blocked frequently, which seriously restricts the normal production. Therefore, according to the actual working conditions, the selection of the inclined scrceen plate and the structural optimization and adjustment of the screen plate were carried out, which completely eliminated the bad factors in the coal transportation system and greatly improved the production efficiency.

Analysizing the reasons of screen plate blocking
1) The screen plate is a polyurethane comb shaped screen plate, the size of the screen hole is approximately a triangular hole of only 50mm, and the overall opening rate of the screen plate is less than 60%.
2) The quality of the power generation coal is relatively rough, containing large size block coal, weeds, wood and other sundry.
3) Due to the high water content of coal, eapecially in the rainy and snowy condition, the damp and wet coal has high absorbability, as a result, the mesh hole is easy to block.
4) There are defects in the structure of the sieve plate, resulting in poor blanking.
Remould the ordinary sieve plate
The feature of ordinary sieve plate
Ordinary sieve plate of circular vibrating screen is a kind of polymer elastic screen plate, it has excellent wear resistance, oil resistance, hydrolysis resistance, bacteria resistance, aging resistance. It can greatly reduce the weight of equipment, reduce the cost of equipment, extend the service life, and reduce the noise. Shape: comb teeth, square hole, long hole, round hole and slot type, the size of the graded material is generally 0.1~80 mm. Due to the different working conditions of polyurethane comb teeth screen plate in the process of use there are still corresponding defects: comb teeth screen plate inclination is small, when the same amount of material processing flow rate is low.The material is easily stuck in the comb perforation, causing the screen area to decrease. Seriously screen clogging, poor screening rate, large labor intensity.
Characteristics of sieve plate
Cantilever bar sieve plate of high frequency tuning fork the rods in the sieve plate vibration at the same time, the second high frequency resonance, make the material move faster, and the speed of screen surface grain material sinking and has small contact screen surface transverse particulate material to the mesh, which increases the probability of through the screen mesh, has certain viscosity of water, by the high frequency vibration shake off, not easy bonding on the sieve article cause congestion, is the ideal viscosity or contain fiber materials sieve plate.
Polyester sieve plate modified to rods sieve plate
The original design of the circular vibrating screen of thermal coal is polyurethane comb shaped sieve plate, with a certain treatment capacity of 200 t/h±10% under the condition of moisture ≤8%, the theoretical screening efficiency is no less than 85%, and the particle size of the material on the sieve is > 30mm. However, due to the difficulty in controlling the moisture and sundries of coal, the sieve plate of coal carding teeth has a relatively high adsorption ability, which causes the clogging of the sieve hole and prevents normal production. In order to meet the production requirements, combined with the characteristics of rods sieve plate, the original installation size was used to change the comb type sieve plate to rods sieve plate, and the opening rate of the sieve plate reached 80%.