Maintenance and care of seed pelletizing machines

Common Faults and Solutions of Melon Seed Cleaning and Grading Machine

The melon seed cleaning and grading machine is a device used to remove impurities (such as stones, soil lumps, broken shells, etc.) from melon seeds and grade them according to standards such as size and fullness. It is widely used in agricultural production and food processing fields. The following are its common faults and corresponding handling methods:

I. Feeding system failure

Poor feeding

Fault manifestation: The speed at which melon seeds enter the machine is uneven, and even blockage occurs, resulting in a decrease in the efficiency of cleaning and grading.

Cause of malfunction

The feeding port is blocked: There may be large debris mixed in the melon seeds, such as branches or plastic bags, which get stuck at the feeding port and prevent the melon seeds from entering normally.

The design of the feeding hopper is unreasonable: The shape, Angle or size of the feeding hopper is not appropriate, causing the melon seeds to accumulate or flow poorly during the feeding process.

Conveying device malfunctions: such as conveyor belt slippage, loose or broken chains, etc., affect the normal conveying of melon seeds.

Solution

Clean the feed inlet: Regularly inspect the feed inlet, promptly remove any debris from it, and ensure it is unobstructed.

Optimize the design of the feeding hopper: Based on the characteristics of the melon seeds and the actual usage conditions, improve the feeding hopper, such as adjusting the Angle of the feeding hopper and adding deflector plates, to ensure that the melon seeds can smoothly enter the machine.

Inspect the conveying device: Check the tension and wear of conveying components such as conveyor belts and chains. Adjust or replace damaged parts in a timely manner to ensure the normal operation of the conveying device.

The feed rate is unstable

Fault manifestation: The feed volume fluctuates, resulting in inconsistent cleaning and classification effects.

Cause of malfunction

Feed regulation device failure: The feed regulation valve or feed motor and other regulating components malfunction, making it impossible to accurately control the feed volume.

Material property changes: The moisture content, particle size and other properties of melon seeds change, affecting their flow performance in the feeding system.

Solution

Inspect and repair the feeding regulation device: Check the sealing performance and flexibility of the feeding regulation valve as well as the operation of the feeding motor, and repair or replace faulty components.

Control material properties: Pre-treat the melon seeds before feeding, such as drying and screening, to ensure that the properties of the melon seeds are relatively stable. Meanwhile, adjust the feeding regulation device according to the characteristics of the melon seeds to ensure the stability of the feeding volume.

Ii. Malfunction of the cleaning system

Impurities are not removed thoroughly

Fault manifestation: After cleaning, the melon seeds still contain a considerable amount of impurities, which affects the product quality.

Cause of malfunction

Screen blockage or damage: The screen is a key component in the cleaning system. If the screen is blocked by debris such as melon seed peels and dust, or if it is damaged or perforated, it will result in the inability to effectively separate impurities.

Air separation system failure: Inappropriate fan speed of the air separation system, blocked air ducts or improper adjustment of air dampers, etc., will affect the magnitude and direction of the wind force, and the light impurities cannot be effectively blown out.

Unreasonable setting of cleaning parameters: For instance, if parameters such as cleaning time and vibration frequency are not set properly, it may lead to poor cleaning results.

Solution

Clean or replace the screen: Regularly clean the debris on the screen to maintain its permeability. If the screen is damaged, it should be replaced with a new one in time.

Maintenance of the air separation system: Check the operation of the fan and adjust the fan speed to an appropriate range. Clear the debris in the air duct to ensure its unobstructed flow. Adjust the air damper reasonably to ensure that the wind force can accurately blow out the light impurities.

Optimize the cleaning parameters: Based on the actual conditions such as the variety of melon seeds and the content of impurities, determine the optimal cleaning time and vibration frequency and other parameters through experiments and set them reasonably.

The breakage rate of melon seeds is high

Fault manifestation: The breakage rate of melon seeds is relatively high during the cleaning process, resulting in increased product loss.

Cause of malfunction

Wear and tear of cleaning components: After long-term use, components such as cleaning rollers and screens may wear out, making their surfaces rough and prone to causing damage to the melon seeds.

Excessive cleaning force: If the parameters such as vibration intensity and wind force during the cleaning process are set too high, the melon seeds will be subjected to excessive external force, which may lead to damage.

Solution

Replace worn parts: Regularly inspect the wear condition of the cleaning components, and replace those that are severely worn in a timely manner to ensure that the surface of the cleaning components is smooth.

Adjust the cleaning force: Appropriately reduce parameters such as vibration intensity and wind force during the cleaning process to prevent the melon seeds from being subjected to excessive external force. Meanwhile, some buffering measures can be adopted, such as adding soft padding inside the cleaning drum, to reduce the collision between the melon seeds and the components.

Iii. Faults in the classification system

Inaccurate classification

Fault manifestation: The melon seeds cannot be accurately graded according to the predetermined standards, resulting in the mixture of melon seeds of different grades.

Cause of malfunction

The size of the sieve holes for grading is inappropriate: If the size of the sieve holes of the grading sieve does not match the grading standard of the melon seeds, it will prevent the melon seeds from being graded correctly.

Improper adjustment of the grading device: For instance, if parameters such as the inclination Angle and vibration frequency of the grading board are set unreasonably, it will affect the grading effect of the melon seeds.

Uneven particle size of melon seeds: If the particle size of the fed melon seeds varies greatly and the adaptability of the classification system is poor, it will also lead to inaccurate classification.

Solution

Replace the grading sieve with the appropriate sieve hole size: According to the grading requirements of melon seeds, select a grading sieve with the appropriate sieve hole size and replace it.

Adjust the parameters of the grading device: Through experiments and adjustments, determine the optimal inclination Angle and vibration frequency of the grading board and other parameters to ensure that the melon seeds can be accurately graded according to the predetermined standards.

Pre-grading melon seeds: Before feeding, conduct a preliminary screening of melon seeds to remove those with excessive particle size differences, thereby enhancing the adaptability of the grading system.

Low classification efficiency

Fault manifestation: The classification process is slow, affecting the efficiency of the entire production process.

Cause of malfunction

The structure of the grading device is unreasonable: The design of the grading device may have flaws, such as narrow grading channels and poor flow of melon seeds, which leads to low grading efficiency.

Insufficient motor power: The motor power driving the classification device is too small to provide sufficient power, causing the classification process to be slow.

Solution

Optimize the structure of the grading device: Improve the grading device, such as widening the grading channel and adding a flow guide device, to increase the flow rate of melon seeds and the grading efficiency.

Replace with a motor of appropriate power: According to the working load and requirements of the classification device, select a motor of appropriate power for replacement to ensure the normal operation of the classification device.

Iv. Transmission System failure

Wear of transmission components

Fault manifestation: The transmission components (such as belts, chains, gears, etc.) show signs of wear, loosening or breakage, leading to unstable operation of the machine and even inability to work normally.

Cause of malfunction

Long-term wear and tear: During the long-term operation of transmission components, due to friction and wear, there will be a decline in performance.

Poor lubrication: Insufficient lubrication of transmission components will increase frictional resistance and accelerate wear.

Overload operation: If the machine is in an overloaded operation state for a long time, it will cause the transmission components to bear excessive loads, leading to their damage.

Solution

Regularly inspect and replace transmission components: Develop a plan for the inspection and replacement of transmission components, and regularly check belts, chains, gears, etc. Replace them in a timely manner if any wear, loosening or breakage is found.

Strengthen lubrication and maintenance: Lubricate and maintain the transmission components at the prescribed time intervals and in accordance with the lubrication requirements to ensure good lubrication.

Avoid overloading operation: Arrange production tasks reasonably to prevent the machine from being in an overloaded operation state for a long time. At the same time, an overload protection device can be installed to cut off the power supply in time when the machine is overloaded, protecting the transmission components.

The transmission noise is loud

Fault manifestation: The machine generates considerable noise during operation, affecting the working environment.

Cause of malfunction

Loose transmission components: such as loose belts or inappropriate chain tension, can cause vibration and noise in the transmission components during operation.

Poor gear meshing: Low processing accuracy of gears, improper installation or wear, etc., can lead to poor gear meshing and generate noise.

Solution

Adjust the tension of transmission components: Check the tension of transmission components such as belts and chains, and adjust the tensioning device to achieve an appropriate tension state.

Maintenance of gear transmission: Check the meshing condition of gears and replace gears with low processing accuracy or severe wear. Adjust the installation position of the gears to ensure they mesh correctly.

V. Electrical System Faults

The motor cannot start.

Fault manifestation: After pressing the start button, the motor does not respond and cannot start normally.

Cause of malfunction

Power failure: such as low power supply voltage, phase loss, blown fuse, etc., can cause the motor to be unable to obtain sufficient power supply.

Motor failure: Faults such as short circuit or open circuit in the motor winding and bearing damage can prevent the motor from operating normally.

Control circuit failure: Faults in components such as contactors, relays, and buttons in the control circuit can affect the starting control of the motor.

Solution

Check the power supply: Use a multimeter or other tools to check if the power supply voltage is normal and if the fuse has blown. If any abnormality is found, deal with it promptly.

Motor maintenance: Conduct insulation resistance tests and winding inspections on the motor to determine if there are any faults. In case of any malfunction, repair or replace it in time.

Inspect the control circuit: Check whether the contacts of each component in the control circuit, such as contactors, relays, buttons, etc., are in good contact and whether the coils are damaged, etc. Replace the faulty components.

Overheating of electrical components

Fault manifestation: Electrical components (such as contactors, relays, motors, etc.) experience excessively high temperatures during operation, and even phenomena like smoking and burning occur.

Cause of malfunction

Excessive load: When the motor or electrical components are in an overloaded operation state for a long time, a large amount of heat will be generated, causing the temperature to rise.

Poor heat dissipation: Inadequate ventilation around electrical components or damaged heat dissipation devices can affect heat dissipation, causing the components to overheat.

Quality issues of electrical components: Some electrical components are of substandard quality, with problems such as excessive internal resistance and poor insulation performance, which can easily lead to overheating.

Solution

Adjust the load reasonably: Check the operation of the machine to avoid long-term overload operation of the motor and electrical components. The load can be reduced by optimizing the production process, adjusting equipment parameters and other means.

Improve heat dissipation conditions: Clear away debris around electrical components to ensure good ventilation; Check the operation of heat dissipation devices such as cooling fans and heat sinks. Replace them in time if any damage is found.

Replace with reliable electrical components: Select electrical components of guaranteed quality for replacement to avoid overheating faults caused by component quality issues.