Rod Mill

Technical characteristics and structural properties

1. The mill works

Induction motor through the coupling, reducer, pneumatic clutch, the pinion, the rotary portion of the large gear driven at a constant speed of rotation, the rotary portion of the barrel grinding media steel rod under the action of centrifugal force and frictional force, is raised to a certain height , was spilled off the state campaign material inside the mill under the impact and abrasive steel bars and crushed, ground minerals from the overflow from the discharge port into the inlet, through the screening, the granularity of qualified products discharged by the sieve a small amount of material from the big screen to drain the end to complete the grinding operation.

2. The main part of the mill

Feeding part, feed department, main bearing portion, the body portion, discharging part, transmission part, discharging sieve Ministry of Basic, slow gear, jet lubrication device, lifting device, high pressure and lubricants station lubrication pipes, main gear, main motor, electrical control systems, plus bars, pneumatic clutch and the gas system, couplings and safety enclosures.

3. Structural features rod mill

3.1 feed block

Mill feed chute way using the pulp with water was added to the tangential direction. At the bottom of the chute laying our own research and development of new utility model patent "chute wear protection", which effectively prevents the material wear and tear on the bottom of the chute, and a large degree of extending the life of the chute.

3.2 feed Ministry

Feed section includes a feed screw barrel, feed and end cap liner and so on. Design spiral structure feeding tube type grinding process according to the requirements. Seal tapered helical tube structure, improve the feed material level, to prevent the accumulation of material in the spiral tube; feed cover to prevent excessive wear and feed inside cover laying liner, liner is generally used in high-manganese steel liner plate, with the impact of hardened, wear and corrosion-resistant properties.

3.3 tubular section

Barrel is the main component of the mill, comprises a barrel, the inner liner and the like. To prevent excessive wear of the cylinder, the cylinder internal laying liner, liner bolted. Rubber pad between the liner and the cylinder, which can effectively cushion the impact of the steel rod of the cylinder, and the cylinder wall liner and make a more snug fit. Outside of the mill shell nut underlying rubber ring and metal plate, can effectively prevent coal slurry flow. Butt weld strength structural form cylinder by other selected cylinder liner material has good impact hardened, wear resistant properties.

3.4 feed Ministry

Discharging portion includes a discharge end caps, end liner, spiral tube and discharge sieve. According to the characteristics of the mill discharge, the discharge portion is provided in the overflow discharge spiral tube, so that qualified fine material discharge overflow, too coarse material from the feed screw return cylinder regrinding. Overflow discharge slurry through a sieve material, the material will be suitable sieve material into pump inlet, while the material is too large, broken sticks and other debris discharged to another spout. The material is a cylindrical sieve sieve sieve sieve cylinder body with wear-resistant stainless steel plate, when considering the need for maintenance downtime or sieve, add the mesh upper cylindrical screen unit and bleed hole cleaning water outlet and the drum sieve set gas emissions should be set at the device, drain away the mill dust and water vapor to escape, etc., and the addition of a spiral structure in the mesh, and promote nesting, they set up the outlet sieve material and sieve material in the lower row Exit.

3.5 main bearing section

Using static and dynamic pressure bearing section bearings can be achieved hydrostatic jacking, dynamic pressure operation. Before the mill is started or stopped before the mill starts high-pressure pumps, high-pressure oil into the bush, so that the oil film between the bearing and the journal, hydrostatic jacking; normal operation after the mill, high pressure pump to stop relying on continuous fed into the Low oil to achieve hydrodynamic lubrication. Main bearing by bearing, bearing, bearing cap and cooling system, etc., are all closed circular 120 ° double rocker self-aligning bearings. Both ends with rubber sealing ring and grease composition sealed structure; serpentine cooling pipes buried under the bush bearing alloy layer, directly cooling the alloy layer; upper set leaching oil installations, ensure continuous lubrication of bearings;

3.6 transmission parts

Mill main drive motor driven gearbox using the form to run the mill pinion driven by pneumatic clutch transmission, pneumatic clutch form, to solve the segmentation starting power equipment, reducing the impact on the grid at the start, to achieve mill smooth start-up, to ensure that the transmission system more secure and reliable.

3.7 pneumatic clutch

Low-speed mill, machinery and equipment, transmission overloads To configure pneumatic clutch according to this feature, you can achieve the motor, the host segments start, which reduces the current impact on the grid when the mill motor starter. Pneumatic clutch is rotating in front of the mill, the motor starts to load, the motor and gearbox together to achieve the speed, DCS control pneumatic clutch by making operational, driven mill at full capacity. Pneumatic clutch has the following advantages:

1) to achieve the main motor no-load start. Shorten the mill start-up time, reduce the starting current, reduce the impact on the grid. So do not consider starting torque increase due to increased motor installed power;

2) enable the mill to achieve a smooth start;

3) In the mill short, intermittent open downtime, allowing non-stop main motor, thereby protecting the start control device.

3.8 Slow gear

Slow transmission auxiliary micro drag to the mill installation, commissioning, maintenance bring great convenience. The device consists of a slow pass motor, reducer and straight tooth clutches and other components. Slow work unit, the main motor off automatically, mill shell can get less than 1r / min speed, so that the mill to easily stay in any desired position and at the same time realize reversing mill. When the motor power outage stopped the slow pass, using a ratchet pawl jammed the barrel can be achieved stall. This structure is simple, safe and reliable. Transmission of electrical, mechanical interlock control, to ensure the safe operation of the mill.

3.9 spray lubrication device

Large mill pinion gear belongs open, with low speed, heavy, continuous work characteristics. Mating surfaces using spray lubrication device. Spray lubrication with pump-driven, high-viscosity oil through the nozzle, timing, quantitative, spray evenly to large and vice surface friction pinion. Extend the life of the gears, improve the operating rate of the mill.

3.10 from the device

The mill for installation, maintenance, repair convenience, set the lifting device. Lifting device from cradle seat, hydraulic jacks, rollers and other components, hydraulic cylinder system, which enables simultaneous uniform lifting, when you need to replace the main bearing lining parts and other maintenance, you can use the lifting device from the rotary portion of the top a certain height, and then along the journal bearing bush slip out or removed for repair and maintenance of other components. After the completion of repair work, when you want to #### the barrel, lifting device can not pay attention to the rapid relief should be used synchronous operation, the cylinder to slow down, to prevent accidental damage to equipment and other key components of the bush.