What equipment is usually installed at the head of the feeding belt to optimize the feeding properties in order to extend the life of the lining plate?

The wear rate of the lining plate of the cone crusher is closely related to the feeding properties. Factors such as iron parts, oversized large blocks, fine powder content, and moisture in materials can directly affect the wear of lining plates. Reasonably configuring pre-treatment equipment at the head of the feeding belt and optimizing the feeding properties is an important technical means to extend the life of the lining plate. This article is based on on-site practice and systematically introduces the main equipment that should be installed at the head of the feeding belt and its working principle.

1、 Iron removal equipment

Iron parts are one of the main factors causing lining plate rupture and abnormal wear. The primary measure to protect the lining plate is to install effective iron removal equipment at the head of the feeding belt.

1. Electromagnetic iron remover

Electromagnetic iron remover is a widely used iron removal equipment, usually installed at the head or middle of belt conveyors.

Working principle: The electromagnetic iron remover generates a strong magnetic field after being powered on. When the material passes through the magnetic field area, the ferromagnetic substances mixed in the material are magnetically adsorbed and regularly removed by the iron unloading belt or manual cleaning.

Installation location selection: When installing the head, the iron remover is arranged above the belt driven drum, where the material is in a projectile state and the iron parts are easy to separate. This layout method takes up less space and is suitable for situations where space is limited. When installed in the middle, the iron remover is arranged above the horizontal section of the belt, which is suitable for process requirements that require multiple iron removals.

Selection points: The magnetic field strength and suction force of the electromagnetic iron remover should be determined according to the material particle size, layer thickness, and belt speed. For larger iron pieces, it is necessary to choose equipment with sufficient suction to ensure that the iron pieces can be effectively adsorbed.

2. Permanent magnet iron remover

The permanent magnet iron remover uses a permanent magnet as the magnetic field source and does not require an excitation power supply, resulting in lower operating costs.

Applicable scenarios: Permanent magnet iron remover is suitable for working conditions with low iron content and small material layer thickness. The magnetic field strength is relatively stable, but cannot be adjusted. When selecting, the appropriate magnetic force level should be determined based on the site conditions.

Limitations: Compared with electromagnetic iron removers, the magnetic field strength of permanent magnet iron removers may decay over time and cannot enhance suction by adjusting the current. For working conditions with a high content of large iron pieces, electromagnetic iron removers are more suitable.

3. Metal detector

Metal detectors are used to detect the presence of metal foreign objects in materials and are interlocked with iron removers or belt control systems.

Working principle: The metal detector is installed above or wrapped around the belt. When a metal foreign object passes through the sensing area, the detector sends a signal to trigger an alarm or control device.

Interlocking control: When the metal detector detects large pieces of scrap iron that exceed the working capacity of the iron remover, it can be interlocked with the belt start button to automatically stop the belt conveyor and manually pick up the iron pieces safely. This interlocking mechanism effectively compensates for the insufficient processing capacity of the iron remover for oversized iron parts.

Actual effect: A certain beneficiation plant adopts a human-machine integrated iron removal method, which combines electromagnetic iron remover with metal detector interlocking control. The average iron passing rate of the crusher is controlled at a low level, and the service life of the lining plate is significantly extended.

2、 Granularity control equipment

The particle size composition of the material has a direct impact on the wear location and rate of the lining plate. Setting screening equipment at the head of the feeding belt can optimize the particle size distribution of the feed.

1. Vibration screen

The vibrating screen is used for particle size classification before the material enters the crusher, separating fine-grained materials that meet the particle size requirements.

Working principle: The sieve box is driven by a vibration motor or exciter to generate regular vibrations. The materials are layered according to particle size on the sieve surface. Materials smaller than the sieve hole size are sieved into undersized materials, while materials larger than the sieve hole size are sieved into the crusher as undersized materials.

The protective effect on the lining plate: The separated fine particles no longer enter the crusher, reducing the abrasive effect of fine particles on the lining plate. At the same time, reasonably control the upper limit of feed particle size to avoid additional impact on the lining plate caused by oversized large blocks. Research has shown that when the feed particle size exceeds the specified value by 10%, it can lead to an increase of approximately 40% in impact load.

2. Rod sieve

Rod sieve is a coarse particle grading equipment suitable for processing materials with high moisture content or high viscosity.

Structural features: Wear resistant bars are arranged at a certain distance to form the screen surface. When materials pass through, large blocks larger than the bar spacing are blocked on the screen surface, while materials smaller than the spacing fall into the lower part through the bar gap.

Applicable scenarios: The bar sieve has a self-cleaning function, is not easily clogged, and is suitable for processing materials with high mud content or high moisture content. Its grading particle size is usually above 50mm, mainly used for pre screening before coarse crushing.

3. Grid sieve

Grid screen is a relatively simple coarse particle grading device, usually installed above the feeding port or at the head of the feeding belt.

Function: Welded from steel rails or plates with a certain spacing, used to intercept large pieces of material that exceed the allowable particle size of the crusher. The intercepted large blocks need to undergo secondary crushing or manual processing before entering the crushing process.

Protective significance: As the last particle size control barrier, the grid screen can effectively prevent oversized blocks from entering the crushing chamber and avoid concentrated impact on the lining plate. Setting a grid screen at the head of the feeding belt is a direct measure to protect the lining plate of the cone crusher.

3、 Feeding homogenization equipment

The uniformity of feeding directly affects the balance of load distribution on the lining plate. Installing a homogenization device at the head of the feeding belt can improve the distribution of materials.

1. Buffer feeding hopper

The buffer feeding hopper is set between the belt conveyor head and the crusher feed inlet, and has the functions of storage and uniform feeding.

Design points: The structural design of the buffer bucket should ensure that the material forms a cushion inside the bucket, reducing the direct impact of the material on the bucket wall. The bottom of the bucket is equipped with adjustable gates or vibrating feeders to control the feeding amount.

The protective effect on the lining plate: By adjusting the buffer feeding hopper, the material entering the crushing chamber can be kept continuous and stable, avoiding sudden changes in crushing force caused by feeding interruptions or flow fluctuations. Stable feeding conditions make the stress state of the lining plate relatively balanced, reducing the risk of local overload.

2. Material sorting device

The material distribution device is used to evenly distribute materials around the crushing chamber to avoid material deviation.

Material distribution tray: Cone crushers are usually equipped with a material distribution tray, which is installed above the moving cone. After the material is dispersed by the distribution tray, it evenly falls into the crushing chamber. The wear and tear of the distribution tray will affect the distribution effect and requires regular inspection and replacement.

Adjustment of feeding port position: Adjusting the horizontal position of the feeding port to make the geometric centerline of the material flow basically consistent with the centerline of the crusher is an important measure to solve the problem of material deviation. When the material flow through the feeding port is mainly concentrated on a part of the cross-sectional area of the feeding port, the distribution tray cannot evenly distribute materials according to the crushing chamber, resulting in uneven wear of the lining plate.

3. Secondary fabric device

For large-scale crushing systems, a secondary material distribution device can be installed at the head of the feeding belt to further improve material distribution.

Structural form: The secondary fabric device usually uses adjustable guide plates or fabric plates to distribute the material before entering the crushing chamber. Experience from a certain site shows that setting up blind spots at the bottom of the crushing chamber can achieve relatively uniform distribution of ore after secondary distribution before entering the crushing chamber.

4、 Moisture control equipment

The moisture content in the material has a certain impact on the wear of the lining plate, especially when it interacts with fine powder to produce abrasion wear.

1. Natural drying field

For materials with high moisture content, a natural drying area can be set up before crushing to reduce the moisture content of the materials through sunlight and ventilation.

Applicable conditions: Natural drying is suitable for occasions with dry climate and sufficient space. By extending the residence time of materials in the drying field, surface moisture can be effectively reduced.

2. Mechanical drying equipment

For working conditions with high requirements for moisture control, a drying device can be installed at the head of the feeding belt.

Equipment type: Common drying equipment includes rotary dryers, fluidized bed dryers, etc. However, it should be noted that drying equipment has high energy consumption and may generate dust emissions, and its use should be evaluated based on the actual situation.

Protection of lining plate: Reducing the moisture content of the material can reduce the adhesion of fine powder on the surface of the lining plate and alleviate abrasion and wear. At the same time, the decrease in moisture improves the flowability of the material, which helps with uniform feeding.

5、 Comprehensive consideration of equipment configuration

In actual production, the equipment configuration of the feeding belt head needs to consider multiple factors comprehensively:

The main function of equipment type is to protect the lining board

Electromagnetic/permanent magnet iron remover removes ferromagnetic foreign objects and reduces liner cracks and impact damage caused by excessive iron

The metal detector detects metal foreign objects and interlocks to compensate for the insufficient processing capacity of the iron remover for oversized iron parts

Vibration screen/bar screen controls the particle size distribution of the feed to reduce the impact of oversized large blocks and alleviate the abrasion of fine powder

Buffer feeding hopper stabilizes the feeding flow rate to avoid sudden changes in crushing force and balance the stress on the lining plate

The material distribution device evenly distributes materials to prevent local wear caused by material deviation

Drying/drying equipment reduces material moisture, decreases fine powder adhesion and abrasion wear

Configuration principle: Equipment configuration should be determined comprehensively based on material characteristics, production scale, site conditions, and investment budget. For working conditions with high hardness ores and high iron content, iron removal equipment is a priority configuration item; For production lines with large fluctuations in feed particle size, the importance of particle size control equipment is more prominent.

Operation and maintenance: After configuring the equipment, it is necessary to establish corresponding operation and maintenance systems, regularly check the magnetic field strength of the iron remover, the wear of the screen mesh, and the integrity of the material separation device to ensure that the equipment continues to function as intended.