Types of crushers

A crusher is a machine designed to reduce large rocks into smaller rocks, gravel, sand, or powder. They are used in the mining industry to break down ore and are an integral part of the processing chain. Crushers are used in construction to reduce the size of construction waste and increase usable materials. With the changed configuration, some crushers can act as screens.

The two main types of crushers are:

Primary This is the initial crusher that breaks down large boulders into smaller rocks and gravel.
Secondary This crusher takes the output of the primary crusher and further reduces the size to produce fine aggregates.

The following list shows some typical types of crushers used in the industry.

Jaw crusher: Often used as the primary crusher, it allows large boulder input and gives a rough output. It works on the principle of a fixed jaw and a movable jaw. The movable jaw applies force and the rock is broken as it gets wedged between the two.
Gyratory crusher: This is the older style primary crusher being slowly replaced by the jaw crusher. It works on a similar principle and is large and bulky. The outer shell is cone-shaped.
Impact crusher: This is a primary or secondary crusher. It crushes rock by striking with the help of a rotor. It is used to produce fine rock dust and is popular for its ability to produce high fines. It gives a better shape than a jaw or cone crusher.
Hammer crusher: It is a type of impact crusher with a rotor that has many hammers mounted on it. The hammer strikes the rock to break it. It is more used for primary crushing.
Cone crusher: This is a popular secondary crusher option. It works like a gyratory crusher but has a flatter shape. A uniform-sized output makes it ideal for making material for the final stage of processing in a sand or gravel pit.
Roll crusher: It gives a product that has a high degree of uniformity and is mostly used in coal or damp material.
Vertical shaft impactors: The material is flung outward when the impeller mounted vertically on a shaft rotates at high speed. They are used as primary and secondary crushers and are known to produce a high percentage of sand and gravel products.

Specifications and Maintenance

Different types of crushers are designed to make a lifetime investment. Nonetheless, these machines also need maintenance to ensure that they perform efficiently for a long time. Here are some of the important crusher components and their maintenance requirements:

Bearings

Bearing maintenance includes cleaning regreasing or replacing the seals. Regular cleaning of the bearings helps to remove dust debris and any leftover old grease. The cleaning should be thorough yet gentle to avoid damaging the bearing's raceways and rolling elements. After cleaning, the bearings should be regreased, ensuring that the grease fills at least 30% to 70% of the bearing's space. During operation, the seals function to prevent contaminants from entering the bearing and keep the lubricant from oozing out. The seals should be checked and replaced whenever they show signs of damage or wear out.
Drive Belts

Typically, the life of the drive belt is determined by the loading condition and the process of operation. Maintenance for drive belts mostly involves inspections for signs of wear or damage. If the belts have cracks, fraying, or any other damage, they should be replaced as soon as possible to prevent further damage to the crusher or other components. Steps should be taken to prevent the drive belt from slipping out of its position and tensioned as per manufacturer's specifications. Referring to the manufacturer's manual can help determine the recommended drive belt tension.
Lubrication System

A crusher's lubrication system should be monitored to prevent any leakage. Lubrication leaks can create friction and eventually cause the crushing machine to overheat, leading to component damage. Additionally, the condition of the lubrication system should be changed regularly as per the manufacturer's instructions. Also, only the recommended lubricants should be used to maintain the machine's performance and efficiency.
Hydraulic System

A crusher's hydraulic system can wear out and tear if there are leaks. For this reason, the hoses and connections of the system should be inspected regularly for any leaks or damages. Additionally, the filters and hydraulic fluids should also be inspected and replaced or cleaned regularly to prevent contamination buildup.
Productovan

Generally, a crusher's productovan is subjected to enormous pressure during the crushing process. Hence, it is important to examine the productovan for any signs of cracks, wear, or damage. Any damages to the productovan can easily disrupt the machine's operation by allowing material to leak into undesired areas. If any damages are found, the wearing parts should be reconfigured or replaced as soon as possible.

Scenarios of types of crushers

Mining industries mostly use the primary crushers and other types of crushers for large-scale operations. They handle massive rocks and feed them into belt conveyors or railway carts. In the mining industry, jaw crushers are particularly popular because they can break down hard ore, granite, and various materials. Some iron ore mines may use gyratory crushers, which can handle even larger volumes.

The main product of a primary rock crushing station is sorted using vibrating screens. Some stones may have a larger size than what is needed for the next stage and will be fed into secondary or tertiary crushers. Gravel lakes and dry river beds often stone crushing machines are used to create sand. Many stone crushing machines manufacturers offer sand makers that resemble vertical shaft impact (VSI) secondary crushers. Sand makers take gravel and crush them into sand for the concrete industry to meet the ever-demanding requirements.

Another large-scale scenario that requires massive stone crushers is road and highway construction. Bitumen mixed with sand gives the strength of the roads, and a considerable portion of sand used in road construction is created with the help of stone crushers. In road construction, aggregate sizes are of significant importance, which is achieved using primary, secondary, and tertiary crushers.

Cement industries also require an extensive stone crushing setup to convert large boulders into the required aggregate sizes for the production of cement. The popular machines used in a cement factory are along the lines of gravimetric, jaw, gyratory, or impact crushers.

Other industries that require various types of crushers include but are not limited to the following:

Glass Manufacturing:Glass crushers have perceiving glass plants and municipal waste management facilities. They help reduce the volume of glass waste for recycling and improve the efficiency of glass processing facilities.
Biomedical Waste Management:Biomedical waste crushers are commonly used in hospitals, clinics, and healthcare facilities. These institutions generate biomedical waste, such as contaminated materials, syringes, needles, and medical equipment.
Additive Manufacturing:In some additive manufacturing materials may need to be reduced in size to achieve the desired particle morphology or distribution for use in 3D printing, powder metallurgy, or other additive fabrication processes.
Power Generation:Some crushers, such as coal crushers or biomass crushers, are used in power generation facilities. These may be thermal plants using coal as the primary fuel or some using renewable or hybrid fuels like biomass. Industries from different sectors use types of coal crushers for facilities that generate energy from coal as the primary fuel.

How to choose Types of Crushers

When buying the types of rock crushers, consider the key factors to ensure the choice aligns with operational requirements. With these factors, buyers can now select the best types of crushers that will meet their needs.

Application Needs

Buyers should first consider their application needs, such as material type, size, shape, and production capacity. Some crushers are better for handling softer materials, while others excel at crushing hard, abrasive substances. For example, a buyer whose aim is to produce sand will go for a fine crushers like impact or sand-making crushers.
Production Requirements

Buyers should consider the production requirements, such as the desired throughput and reduction ratio. Different types of crushers offer varying levels of efficiency and capacity. Assessing the required production targets will help in selecting a crusher that can meet the desired output. For instance, buyers needing high-volume production may opt for cone crushers, known for their superior crushing capacity.
Power Consumption

When choosing a type of crusher, buyers should consider the power consumption and operating costs. Evaluating the cost implications of power usage will help to choose a compatible crusher with efficiency goals and budget constraints.
Installation and Maintenance

Also consider the maintenance and installation requirements. The types of crushers to be considered should have a simple, accessible maintenance process. This could reduce downtime and maintenance cost. Furthermore, the availability of spare parts should be considered, as this will enable quick replacement service to ensure continuous operation.

FAQ

Q1: What are the primary and secondary crushers?

A1: Primary crushers are machines that break down large rocks into smaller, manageable pieces. They handle the initial stage of crushing and typically produce coarser outputs. Secondary crushers follow the primary crushers in the crushing circuit. Their main job is to further reduce the size of the material produced by the primary crushers. Secondary crushers provide a finer output that is often used in the manufacturing of final products.

Q2: What are the impacts of crushers?

A2: The impact crushers work by striking the material. The process involves using a fast-spinning rotor that throws the material against fixed elements in the machine's chamber. These could be anvils or walls. The impact force breaks the material down. This type of crusher is suitable for tackling harder and more solid minerals and rocks.

Q3: What are the mobile and stationary crushers?

A3: Mobile crushers are compact machines that can move around a site or between locations. They are ideal for projects where the source of material is in constant movement or where space is limited. Mobile crushers can also reduce the need for material transport. Stationary crushers are fixed machines that usually process large volumes of materials continuously. They typically have a higher production capacity than mobile crushers.