Summary:In recent years, the gravel aggregate industry has been developing in the direction of ecological, environmental and sustainable development.

In recent years, the gravel aggregate industry has been developing in the direction of ecological, environmental and sustainable development. Gravel aggregate has become a huge and essential raw material in construction projects such as bridges, water conservancy, roads and so on.

However, due to factors such as market, raw materials and the level of design units, there are some problems in the production and operation of many sand and gravel production lines, which can not achieve the expected results.

This paper analyzes the common problems and corresponding improvement measures of sand and gravel aggregate production line for reference only.

mobile construction waste crushing process

1. Selection of basic equipment

he success of gravel aggregate production line mainly depends on reasonable equipment selection, which is generally determined by material hardness, soil content and corrosivity index.

Some production line investors do not find formal design units, or copy the equipment selection of other enterprises, which does not meet their own production reality, which will lead to unreasonable selection and other problems.

aking basalt, granite, diabase and other materials with high corrosivity index and hardness as an example, in order to pursue better product particle size, hammer or impact crushers are mostly used in the production line. However, the equipment consumption of such crushers is large, and vulnerable parts such as hammer head or impact plate are frequently replaced, resulting in relatively high production cost, which is not conducive to market competition.

For this problem, even adjusting the process is difficult to completely solve. Only by replacing the extrusion crusher, such as cone crusher, can we ensure the stable operation and sustainable development of the production line.

2. Material transfer drop

1) There are two main drop positions causing material transfer and transportation: vibrating screen inlet, coarse breaking outlet and vibrating screen inlet. When materials enter the vibrating screen, the large drop between them will inevitably cause a certain degree of impact on the screen plate, thus wearing the screen plate.

Improvement measures:

The reserved distance can be adjusted appropriately to reduce the wear of the screen plate, or the waste belt conveyor belt can be installed in the impact area of the screen plate head of the vibrating screen to reduce the impact of materials on the screen plate.

2) The coarse breaking equipment usually has a concrete structure foundation, and there is a large drop between the discharge port and the conveyor belt machine. The coarse breaking discharge will cause loss to the belt machine and even smash the buffer roller.

Improvement measures:

he buffer bed can be used to replace the buffer roller to reduce the impact and wear of materials on downstream equipment; In addition, in case of great drop, if the space for equipment layout is sufficient, buffer equipment can be added to buffer and reduce the equipment loss caused by drop.

3. Wear of material chute

Sand and gravel aggregate products have the characteristics of multi edges and corners, and some materials have certain abrasiveness. In addition, there are problems such as large drop in the process of material transportation, which shorten the service life of the material chute and seriously wear and impact.

Improvement measures:

Lining plate shall be laid inside the chute with large impact force; For the chute with small impact force, the steel plate of the material chute shall be thickened as much as possible, and the material abrasive shall be finished inside the chute. This design should be avoided for materials easy to block.

4. Silo

The sand and gravel aggregate production line includes product storage, stone powder storage, coarse crushing feeding bin, medium and fine crushing and sand making buffer bin.

1) The coarse broken feeding bin mainly designs the side discharge port of the bin as a "door" rectangular structure. If there is a dead angle between the discharge port and the bin, it can not discharge smoothly, and it is easy to accumulate large materials, making normal feeding impossible.

Improvement measures:

An excavator can be placed next to the feeding port for material cleaning at any time.

2) In the off-season, the side outlet of the feeding bin is reconstructed and the "inverted eight" trapezoidal structure is adopted to facilitate the removal of the dead corner of the accumulated material. The bottom design of medium fine breaking and sand making buffer bin is mostly flat bottom steel bin structure. During the operation of the production line, if the overall material pressure at the bottom of the bin is too large, the bottom of the steel bin will sink and denature, which may lead to serious potential safety hazards.

Improvement measures:

In this case, it is necessary to improve the reinforcement of the warehouse bottom. The flat bottom steel warehouse structure shall not be used in the design as far as possible. If the flat bottom warehouse structure cannot be avoided, the warehouse bottom of concrete structure can be selected.

5. Environmental issues

The environmental quality of the formally designed production line must meet the international requirements, but there are still some production lines located in the finished product loading garage and near the secondary impact crusher with relatively large dust.

Improvements:

In response to this problem, you can first calculate according to the location and number of dust collection points, and place dust collectors with sufficient air volume in front of and behind the crusher discharge point to reduce dust.

If it is dust near the finished product loading garage, in addition to the dust collector, a centrifugal fan can be placed between the dust collector on the top of the warehouse and the bulk machine, and water spray can be placed at the discharge port of the bulk machine to reduce dust.

Unorganized dust is generated when the material is stacked, and the stacking height and capacity can be calculated to add a water spray dust removal device.

6. other questions

1) When the production line is running, the excessive load of the vibrating screen to the feeder often causes the gears of the exciter to wear. For the problem of wear and tear, it is usually possible to reduce the wear and tear of the equipment by adjusting the installation angle of the production line equipment, or increasing the slow start of the inverter.

2) In addition, due to design problems, individual conveyor belts will have a series of impacts on production due to the incompatibility of models. In this regard, the speed of the belt conveyor can be driven by replacing the drive system to increase the conveying capacity.

3) In view of the material leakage caused by the damage of the inlet and outlet of the vibration equipment, the waste belt conveyor tape can be used to replace the soft and not durable canvas, so as to strengthen the sealing of the equipment and prolong the service life of the equipment.