What Makes Peanut Belt Conveyors Essential in Processing

Daily Maintenance and Comprehensive Repair Manual | A Key Guide to Ensuring Peanut Roasting Quality and Production Efficiency

The flat belt hot air oven dryer is the core equipment in the peanut kernel roasting process. It uses a hot-air circulation system to uniformly and efficiently roast peanut kernels, directly affecting the final product’s color, aroma, crispness, and shelf life. The sustained stable operation of the equipment relies on a scientific daily maintenance system and timely fault repair.

Main Structural Components

• Conveyor System: Drive motor, reduction gear, drive roller, driven roller, tensioning device, and high-temperature resistant conveyor belt.
• Heating System: Burner (or electric heating elements), heat exchanger, and combustion chamber.
• Ventilation System: Circulation fan, exhaust fan, air duct, and damper adjustment device.
• Control System: Temperature control, speed control, air volume control, and safety protection devices.
• Frame Structure: Support frame, insulation layer, and inspection doors.

Workflow: Peanut kernels are evenly spread on the conveyor belt and move slowly with it. Hot air penetrates the material layer from below or above, removing moisture as it roasts. The entire process requires precise control of temperature, air velocity, and material dwell time to ensure uniform roasting without over-processing.

Daily Maintenance System

Establishing a systematic daily maintenance system is the foundation for preventing equipment failure, extending service life, and ensuring production stability. The following maintenance plan is based on equipment operating hours and importance.

1. Daily Inspection Items

Inspection Item	Inspection Content	Standard Requirement
Conveyor Belt System	Tracking deviation, damage, material buildup	No deviation, no damage, no material buildup
Transmission System	Vibration, noise, bearing temperature	Smooth vibration, normal noise, temperature < 70°C
Hot Air System	Burner flame, pressure parameters	Stable flame, pressure within set range
Ventilation System	Fan operation, air duct sealing	Smooth operation, no air leakage
Control System	Instrument display, safety devices	Accurate display, effective protection functions

2. Weekly Maintenance Items

Cleaning Work: Thoroughly clean dust and material residue from the conveyor belt, inside the air duct, and on the heat exchanger surface. Pay special attention to blockages near the exhaust port.

Lubrication Work: Apply an appropriate amount of high-temperature-resistant grease to transmission chains, bearing housings, guide rails, etc., to prevent lubrication failure at high temperatures.

Tightening Check: Check and tighten all bolt connections, especially at the conveyor belt joint, fan base, and hot air pipe flanges.

3. Monthly Maintenance Items

• Comprehensive Conveyor Belt Check: Check the strength of the conveyor belt joint and measure belt elongation (not exceeding 2% of original length).
• Transmission System Disassembly Inspection: Check gear wear in the reducer, change lubricating oil; check bearing clearance of drive and driven rollers.
• Heat Exchanger Deep Cleaning: Thoroughly clean heat exchanger fins with compressed air or specialized cleaning agents to restore heat transfer efficiency.
• Fan Balance Check: Check the fan impeller for dust buildup or wear, and perform dynamic balancing correction if necessary.
• Safety Device Calibration: Check and test safety valves, pressure gauges, and other safety protection devices.

Safety Reminder: Before performing any maintenance or repair, power and gas sources must be disconnected, and lockout/tagout procedures followed. Allow the equipment to cool sufficiently after shutdown to avoid burns. In peanut dust environments, use explosion-proof tools and strictly prohibit open flames.

Common Fault Diagnosis and Repair

Timely and accurate fault diagnosis and repair are key to reducing downtime and production losses. Below are methods for handling common faults.

1. Conveyor Belt Tracking Deviation Problem

Fault Phenomenon: The conveyor belt shifts to one side, causing uneven material distribution and, in severe cases, potentially damaging the frame through friction.

Possible Causes: Non-parallel roller axes; uneven tension; uneven material adhesion on the belt surface; frame deformation.

Solution: Adjust the bearing seat position of the driven or guide roller; adjust the tensioning device; enhance the cleaning device; correct or reinforce the frame.

2. Unstable Hot Air Temperature

Fault Phenomenon	Possible Causes	Solution
Large temperature fluctuations in the drying chamber, uneven peanut roasting	Burner malfunction; heat exchanger scaling; temperature sensor failure; damper control failure	Clean burner nozzle; clean heat exchanger; calibrate or replace temperature sensor; check damper actuator

3. Fan Abnormal Vibration and Noise

• Fault Phenomenon: Significant vibration during fan operation, accompanied by abnormal noise.
• Possible Causes: Imbalanced impeller; bearing wear; loose anchor bolts; blocked air inlet; poor alignment between fan and motor.
• Solution: Clean impeller or perform dynamic balancing correction; replace fan bearings; tighten connecting bolts; clear air inlet debris; re-adjust alignment.

4. Repair Case: Solving Uneven Roasting Problem

Problem Description: A peanut processing plant’s dryer experienced uneven roasting, with significant color differences in the same batch of peanut kernels.

Diagnosis Process: Measured temperatures in different areas of the drying chamber, found a front-to-back temperature difference of 25°C (standard: within ±8°C). Inspection revealed severe dust buildup on the circulation fan impeller, partially detached air duct deflectors, and clogged mesh on sections of the conveyor belt.

Repair Measures: Cleaned fan impeller and performed dynamic balance test; repaired air duct deflectors; replaced sections of conveyor belt; optimized damper opening settings.

Effect Verification: After repair, the temperature difference was reduced to within ±5°C, and the product qualification rate increased from 78% to 95%.

Preventive Maintenance Plan and Records

Preventive maintenance is a systematic approach to preventing equipment failure through regular inspection, maintenance, and component replacement, significantly reducing unexpected failures and repair costs.

Annual Maintenance Schedule

Quarter	Maintenance Item	Responsible Person	Completion Status
First Quarter	Comprehensive electrical system inspection, clean control cabinet, calibrate sensors	Electrical Engineer	□ Pending □ Completed
Second Quarter	Check and replace worn conveyor belt components, check reducer oil level	Mechanical Technician	□ Pending □ Completed
Third Quarter	Clean the heat exchanger, inspect the burner, and test the safety devices	Thermal Technician	□ Pending □ Completed
Fourth Quarter	Annual overhaul, comprehensive performance testing, formulate next year’s plan	Maintenance Team	□ Pending □ Completed

Spare Parts Inventory Suggestions

• A Class (Critical Wear Parts): Conveyor belt joint materials, burner nozzles, fan bearings, temperature sensors (maintain minimum safe stock).
• B Class (Important Rotating Parts): Reducer, frequency converter, PLC modules (establish quick response agreements with suppliers).
• C Class (General Low-Cost Parts): Standard bolts, sealing strips, lubricating grease, general relays (maintain reasonable stock levels).

Energy Efficiency Optimization Suggestions: Installing waste heat recovery devices can save 15-20% energy; using nano insulation materials can reduce heat loss by 10-15%; installing frequency converters to automatically adjust fan speed based on load; implementing preventive maintenance can reduce unexpected failure rates by 60% and repair costs by 30%.