Apron Feeder Technical Specifications and Maintenance

Technical Specifications

Project Name: ZBWJ160010

Pan Width: 1600mm

Overall Length: 10000mm

Feed Speed: 0.026 – 0.26m/s

Production Capacity: 200 – 1500t/h

Feed Particle Size: <1500mm

Adjustment Distance of Tensioning Device: 300mm

Installation Inclination Angle: 0°

Working principle

The operation of the Apron feeder is driven by the rotation of the motor, which is transmitted through the coupling and reducer to rotate the main shaft device. The chain wheel on the main shaft engages with the chain to drive the chain plates to move in a straight line, achieving the purpose of delivering the materials on the chain plates to various crushing, screening or transportation equipment. The direct-acting reducer in the drive device is equipped with a reverse limiter to prevent the machine from reversing when it stops. The speed of the feeder is adjusted by the frequency conversion device.

Apron feeder structure and components

Drive unit

The drive unit is composed of the main motor, coupling, direct-acting planetary reducer, drive frame, torque rod, etc. Its main function is to provide power for the apron feeder.

Spindle assembly

It is composed of an electric motor, a coupling, a direct-acting reducer, a planetary reducer, a locking disc, and other components. This assembly is a floating-type direct-acting axis support. The spindle is fitted inside the output shaft of the planetary reducer and is connected to it through the locking disc. Its features include no foundation weight, light weight, and a large speed ratio. Due to the use of a floating support, the additional bending moment caused by installation errors on the shaft is reduced, thereby extending the service life of the transmission shaft and facilitating disassembly and assembly.

Tightening device

It is a spiral rod tightening mechanism, mainly composed of an axle, two ends equipped with rolling bearings, bearing seats, locking nuts and tightening rods, etc. The idler wheel is fixed on the axle through an expansion sleeve. At both ends of the axle, there are double-row radial spherical roller bearings and bearing seats. The bearing seats are installed on both sides of the frame and slide back and forth between the guide rails. The tightening device is used to tighten and adjust the horizontal position of the chain. It ensures that the chain is neither too loose nor too tight, allowing it to run smoothly. The idler wheel plays the role of guiding and supporting the chain plate. By adjusting the tightening rod, the tension of the two chains can be made uniform. When the chain plate suddenly receives an impact from the material, the composite spring can act as a buffer, protecting the chain plate and other components from damage.

Chain plate device

It is composed of conveying chain plates, chains, etc. The conveying chain plates are of single circular arc joint type and are made by welding low-alloy steel plates. It has high strength, is wear-resistant, does not leak materials, and has strong impact resistance. The chains are the crawler chains for bulldozers (tank chains) produced by specialized manufacturers. Their characteristics are small pitch error, smooth movement, high strength, large pulling force, and the chains have self-lubrication devices and sealing devices. The shaft is made of hardened steel. After hardening, it improves the toughness and impact resistance of the traction chain, has good wear resistance, and has a long service life.

The sealing device prevents abrasive substances from entering the internal parts of the chain plates, avoiding premature wear and extending the service life of the traction chain by 20-30%. The traction chains with the sealing device and self-lubrication device can reduce friction, lower maintenance costs, and increase the service life. It is convenient to disassemble and replace the traction chain during replacement.

Frame

The frame of the Apron Feeder is made of a steel plate welded I-shaped structure. Several stiffening plates are welded between the upper and lower flange plates. Two I-shaped main beams are assembled by several channel steels and welded into a single unit. It has sufficient strength and rigidity. The weld seams are firm, beautiful, and uniform. The profiles and plates used in the manufacturing are made of high-quality steel. The surface of the materials is pre-treated by grinding, shot blasting or acid washing. After welding, the stress is removed to ensure that there is no damage or deformation on the appearance.

Supporting wheel

It is composed of a support, rolling bearing, shaft, roller, sealing ring, cover plate, etc. Its main function is to support the working section of the chain to prevent the chain plate from generating a large deflection due to load and self-weight, ensuring the normal operation of the chain and bearing part of the material impact and pressure from the silo. Additionally, it can limit the chain deviation and the supporting wheel is of maintenance-free type. It is arranged at intervals on the apron feeder and is placed on the equipment for ensuring the normal operation of the support plate during operation. It is fixed on the frame using bolts. The bearings of the supporting wheel can withstand high impact loads. The bearings are maintenance-free, self-lubricating, and have a long service life.

Sprocket wheel

It is composed of a support, rolling bearings, shaft, rollers, sealing rings, and cover plates, etc. Its main function is to support the return chain plate and prevent significant deflection caused by the self-weight of the chain plate, which could affect normal operation.

Operating Procedures and Maintenance

During the operation of the Apron Feeder, a certain thickness of material should always be maintained on the chain plate. Generally, it should not be less than 500mm. It is not allowed to place materials directly onto the chain plate when it is empty. When it is unavoidable to empty the feeder, a layer of crushed materials should be laid on the chain plate before discharging to prevent direct impact on the chain plate. When large pieces of materials are blocked, blasting is not allowed to remove them.

The distance between the discharge port and the chain plate after equipment installation should not be less than 1.5-2 times the maximum size of the largest material. This ensures smooth material flow and prolongs the service life of the chain plate. After the guard plate is installed, there should be an 8-13mm gap between it and the sides of the chain plate. This prevents material overflow and friction between the material and the guard plate, generating noise. The distance between the bottom edge of the guard plate and the surface of the chain plate should be maintained at 5-10mm to prevent material overflow. The clearance between the axis line of the tensioning device and the rear wall of the silo should be left with a certain space, generally 350-500mm, for easy maintenance and disassembly.

When the pitch of the belt chain wears down to more than 7mm, the bearing sleeve should be turned by an angle or a new chain should be replaced.

When installing the main shaft device rolling bearings, the minimum radial clearance should be ensured to be around 0.08mm. The reduction in radial clearance should be between 0.09-0.11mm. The minimum clearance of the tensioning device rolling bearings should be ensured to be around 0.55mm. The reduction in radial clearance should be between 0.06-0.07mm.

To ensure the normal operation of the apron feeder and its optimal performance, maintenance must be carried out according to relevant requirements. Regular lubrication of each lubrication part should be performed, and all components and fastening screws should be adjusted and tightened.

Only after disconnecting the power supply of the apron feeder drive device and the feeding system can the equipment be repaired or cleaned. Do not climb on the running equipment.