Bulk Material Handling Equipments: Advantages, Disadvantages & Maintenance

In this article, I will share with you different types of bulk material handling equipment, their advantages and disadvantages and how to maintain them.

Before I go too deep into this topic, there are some terms in bulk material handling I would like you to know.

Bulk material handling deals with transporting, packaging, stocking, distribution and storage of dry materials that are powdery, granular or lumpy and are stored in heaps.

We handle these kinds of materials in bulk because their nature doesn’t allow them to be handled as a unit.

These materials will need equipment that can handle the nature of these materials.

In most of these machines that handle bulk materials, you will notice that they have a surface or a bucket to hold these materials as they are being conveyed from one part to another.

These types of equipment make it easier for the materials to be handled without wasting them thus saving so much time.

There are several types of equipment that are used in bulk material handling which are as namely;

Bucket elevators.
Belt conveyors.
Screw conveyors.

Slat conveyors.
Vibrating conveyors.
Pneumatic conveyors.

Chute conveyors.
Gravity conveyors.

Equipment used in bulk material handling

1. Bucket elevators.

Buckets elevators are used to raise and lower materials at a considerable height.

They are mostly used for this purpose because they can raise a large amount of material within a short period.

This is very essential in the time saving and effective handling of these materials.

Bucket elevators from the name, contain several buckets that are mounted vertically on either belts or chains that are parallel to each other running on two fixed rollers.

The chains or the belt are usually fixed at the two roller wheels or you can say pulleys so that they keep moving continuously around these roller wheels, since one is at the top while the other roller wheel is at the bottom.

To prevent spillage of these materials, the buckets are enclosed in a single housing that covers the entire bucket elevator and only inlet and outlet openings are allowed.

When the belt or the chain rotates, it creates a centrifugal force which enables the discharge of the materials from the bucket.

Since this equipment depends on the centrifugal force to deliver the material where it’s needed, it will not be suitable for handling some materials.

The materials that are supposed to be handled by this equipment should be dry for it to work efficiently.

Bucket elevators can’t handle materials that are wet since they will stick in the bucket, fine powder since it will cause dust problems, especially if it’s windy and large lumps of material since it will cause a breakdown by jamming the belt.

The key components of bucket elevators are a head roller, tail roller, belt or chain and leg.

Maintenance of bucket elevators.

The bucket elevators need to be lubricated on the moving parts; the tail roller and head roller.

You have to ensure that the belts, or chains are well tightened when they are loose.
We should fasten the buckets that are mounted on the belt or chain when they are loose.
The buckets and the belts should be cleaned regularly.

2. Belt conveyors.

Belt conveyors consist of endless belts that are rounded over two main rollers. One roller is being powered by a motor to facilitate the movement while the other is being driven.

In the space between the main roller and the trailer, there are rollers are fixed to support the weight of the belt and facilitate the movement of the belts.

Supporting the weight of the belt reduces the load on these belts, hence reducing friction too.

The rollers also reduce the sag of the belt and define the form of the belt, e.g. trough or flat.

The main advantage of troughing is that spillage is reduced at a great rate and the carrying capacity is increased.

You have to understand that the belt will be horizontally, so troughing will do a big deal in preventing wastage of these materials being handled.

The main components of belt conveyors are; trail roller, driver roller, idlers (rollers), belt and scraper.

The main function of the scraper is to keep the belt clean from any sticking materials.

If you want to know more about what is needed to make this belt drive efficient, then don’t forget to check the article below.

The materials to be handled by belt conveyors should not be too wet since they will stick on the belt and not too fine since they will be blown away by the wind.

You might like this: Factors Affecting Efficiency Of Belt Drive Systems

Advantages of belt conveyors.

The belt conveyors usually run smoothly, they are silent and continuous.
It has no restrictions on the type of material it can handle; it can handle light, fine, coarse, wet and dry materials.

Belt conveyors can handle hot materials up to 160⁰C
You don’t need much power to use on belt conveyors; since they are lighter.
With belt conveyors, you can choose any point to unload your materials which is very different from the bucket elevators.

Disadvantages of belt conveyors.

Rubber belts in belt conveyors will not last long if the material being handled is abrasive or sharp.
Belt conveyors require constant maintenance because of their designs and belts.

The belt conveyors can’t be run too first since there will be a risk of excessive wear of the belt.

Problems in belt conveyor systems.

The belt conveyors usually get the bushes fractured due to overloading.

Another common problem in belt conveyor systems is the misalignment of the pulleys.
There is excessive roller wear if lubrication of the rollers is neglected.

3. Screw conveyor.

A screw conveyor is another bulk handling material equipment that most industries prefer using since it doesn’t allow spillage.

It consists of a screw which can either be helical or spiral mounted on a shaft which is enclosed inside a tunnel of a tube.

The shaft that the screw is mounted on it’s connected to an electric motor that drives it.

When the motor is started, the screw rotates, moving the materials from one end to another.

The movement of these materials is made possible by the screwing action of the screw.

A screw conveyor can handle a wide range of materials from vicious and sticky to hot materials since the screwing actions don’t allow too many of these materials to stick.

Advantages of screw conveyors.

Screw conveyors are small in size, hence they need a little space for installation.
They can handle very fine materials since they are dust-tight.
Due to the smaller size and their compatibility, they are very easy to install.

With the screwing action they provide, they convey a wide range of materials under different conditions.

Disadvantages of screw conveyors.

Due to the smaller sizes, they have a limited unit length, which makes it harder to handle a large amount of material at once.

The screwing action is not fit for all materials since it can break them down, in case they go under the screw.
The sticky materials can build up along the screw, reducing its efficiency and carrying capacity.
The screw conveyors are difficult to clean because they are enclosed and also it’s a hassle to clean the screw.

They cannot handle materials that are corrosive since they will corrode the screw.
It takes ages to handle materials since the screwing action is very slow.

Maintenance of screw conveyors.

Lubrication of the bearing is necessary since it aids the screwing action of the screw conveyor and prevents corrosion of some parts.
The screw conveyors’ bolts should be tightened whenever they are loose.
The screw should be inspected regularly for wear and replaced when it’s completely damaged.

Replacing of bearing, casing and any other parts that are worn out.

4. Slat conveyors.

This is a conveyor that has a surface for conveying the material which is made of spaced wood or metal slats fastened at their ends to chains running on a suitable guide track.

The movement of these chains helps to convey the material from one end to another.

We use these types of conveyors in wear housing to carry heavy units and wet materials.

Maintenance of slat conveyors.

Cleaning is the first thing that should be done to remove the dust and debris of materials left off the top of the woods or metal and in between them.
Lubrication of the moving parts is essential to ensure that they move smoothly.
We should inspect the chain for wear and replaced if damaged.

There should also be inspection and testing of the devices that are used to make a record of the weight of the material on the slat conveyor.

5. Vibratory conveyor.

This type of conveyor conveys materials from one point to another through vibration, hence the name vibratory conveyor.

It consists of a trough that is mounted on a leaf spring which is counter-balanced by a coil spring.

We attach the vibrator to the trough so that when it vibrates it shakes the trough and imbalances the spring, resulting in forward catapulting action thus conveying the material to the needed point.

When the vibration is turned off through returns to its original position and another material is placed on the trough and the process repeats itself.

6. Pneumatic conveyor.

Pneumatic conveyors are mainly used for handling materials that are in powdered form and small objects that air can blow easily.

They can be granules or even grains.

We divided the pneumatic conveyors into two systems, namely;

Pressure system.
Vacuum system.

The pressure system; is the one in which air is blown into the conveyor tubes that contain the materials to be conveyed, which are fine granules and end up picking them up.

The air blown into the conveyor should be of high pressure.

The vacuum system; works by the principle of suction to move the material from one point to another.

The materials are usually carried in suspension.

Advantages of the pneumatic conveyor.

There is no spillage since the material is being handled within a pipe.

There is no dust since the materials are conveyed in an enclosed pipe.
It facilitates the drying of wet materials while it’s conveying them.
You can feed this conveyor at different points at the same time and the materials will still be handled.

It’s very easy to use since it has no complicated parts or control system.

7. Chute conveyors.

Chute conveyors convey material by the use of gravity.

It consists of structural steel and a piece of sheet metal shaped like a funnel through which the materials will be put through.

At a certain elevation, the chute branches and that is what is used to take materials to their destination.

A material is placed through a hopper, and since it has a certain angle of elevation, this allows materials to flow freely from the top to the bottom by the use of gravity.

These conveyors are used to handle goods that don’t need any care. It’s not safe for fragile goods.

Design factor of chute conveyor.

The angle at which the chute is placed should not be to slip as it might end up damaging the material.
The material being conveyed through this conveyor should not be wet as it will stick resulting in fewer materials being conveyed.
The cost of construction of the chute conveyor should not be too high.
There should be a low coefficient of friction between the sliding surface and the material being conveyed to facilitate the ease of movement of these materials.

8. Gravity conveyor.

A gravity conveyor is kinda similar to a chute conveyor except to the point that a gravity conveyor has steel rollers mounted on a frame wall with a high elevation where the materials are placed to slide down by gravity.

If you want to know more about the design factor of this gravity conveyor, you can check the article below.

You might like this: 4 Design Factors Of a Gravity Conveyor/ Roller

That is all about bulk material handling equipment. If you have any questions leave your comment.

Thanks for reading, if you have any questions leave your comment. See you in my next article.

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