Sand saws are widely used in the stone industry. Almost all stone processing companies need sand saws, which have the advantages of fast processing speed and high product quality. There are three major problems in the operation of sand saws that users have been difficult to solve:
(1) How to improve the quality and production efficiency of large plates and reduce losses.
(2) How to save high electricity bills.
(3) How to extend the service life of the sand saw (overhaul period).
Problems with the original sand saw electric control system:
(1) Due to the imperfections of the current equipment, the equipment speed cannot be adjusted and the best production efficiency cannot be achieved.
(2) The sand saw motor adopts the star/delta starting method, which has a large starting current when switching, which has a large impact on the equipment and the power grid.
(3) The equipment speed cannot be adjusted smoothly, and the processing technology cannot be adjusted according to the material.
2. Design and working principle of sand saw frequency conversion system:
Our company uses ED3100 series high-performance general-purpose frequency converter to transform the sand saw. By adjusting the running speed of the motor, the sand saw can be started at a low speed when starting, and there will be no current impact to protect the equipment. High-speed operation during normal operation improves production efficiency. Run at low speed when production is about to end to reduce the chance of pulling the board. When stopping or emergency stop, the brake system is adopted to shorten the stopping time. Make the sand saw achieve the best results in different working conditions.
3. Solutions and effects of sand saw frequency conversion system:
(1) Speed regulation On top of not changing the control method of the original equipment, the speed regulation function is added. It is enough to press it once when starting, and there is no need to start several times continuously.
(2) Safety Intranet of the power grid: surge voltage is greatly reduced, and surge current is significantly reduced; external power grid: good terminal conditions minimize the load on the external network.
(3) Consumption reduction Reduce the loss of raw materials and reduce equipment wear.
(4) Energy saving Save energy and reduce power consumption.
(1) The original operating system and safety protection of the equipment remain unchanged, and frequency conversion is used for speed regulation. Realize processing and cutting according to different materials and different processes, improving the quality and production efficiency of large plates. When cutting the material, lower the speed, and when the saw tooth completely cuts into the stone, accelerate the operation again, so that it is not easy to run knife, and there will be no wave pattern on the stone slab. When cutting to the last ten centimeters, lower the speed so that it is not easy to pull the board. When the cut material or the stone has cracks, lower the speed and lower the cutting speed at the same time. If the speed is slow, the impact can be reduced. The stone is not easy to break and does not pull the board, which reduces the loss. It can help stone processing enterprises to achieve their own unique processing technology technically.
(2) The frequency converter is used to digest the instantaneous surge voltage and surge current generated during the working process of the sawing machine. Compared with no frequency converter, there are fewer internal network surges and transient changes when the equipment starts/switches and the crankshaft reciprocates. The vibration of other equipment is almost non-existent. Directly reduce the external network load to protect the safety of electricity use.
(3) The improved technology of frequency conversion speed regulation can maximize the reduction of raw material loss, increase the output rate, reduce the cost, and improve the competitiveness. Eliminate the hard start and stop of the equipment, reduce the wear of transmission and moving parts, and adjust the speed linearly, so that the lubrication system and the transmission and moving parts can be warmed up synchronously. Thereby extending the service life of the equipment, reducing the number of overhauls, and increasing the utilization rate of the equipment.
(4) Reduce power consumption, save electricity expenses, reduce production costs and increase profits.
(5) The maintenance is simple, the machine adopts dust-proof and anti-corrosion design, no special maintenance is required.
Fourth, the problems that should be paid attention to in the transformation of sand saw frequency conversion speed regulation:
(1) Overcurrent problem: Because the sand saw has a large inertia, the current is relatively large when starting, so the inverter should be selected at a power level higher than the motor when selecting.
(2) Overvoltage problem: Because the equipment has a motor that links the flywheel through a belt, and then links the saw blade through the crankshaft, the flywheel generates regenerative voltage during operation, which causes the inverter overvoltage protection. Prolong the acceleration and deceleration time or add a braking unit and braking resistor.
5. Frequency conversion wiring diagram:
6. Concluding remarks:
To sum up, the frequency converter is very useful in the application of the stone industry, which is the future direction of technology development. It is not only energy saving, but also good adjustment performance, which improves the quality of products and enhances the competitiveness of enterprises.