What is the Purpose of Crushing?
Crushing is simply the process of breaking down larger materials into smaller pieces suitable for transportation and processing. There are a variety of crusher machines that each hold their own advantages depending on the task at hand. All of these machines essentially break down the original material and the smaller material exits through a hole at the bottom of the machine. Some machines are compound machines that take a material and run it from one machine to the next. This article will detail out specific types of crusher machinery, detail how each machine works, provide advice on how to increase machine efficiency, detail safety measures for machine use, and help guide an accurate machine choice for a specific job. Whether rocks, boulders, or various other large materials are being crushed, there is a machine for each material and the desired outcome consistency.
The Three Main Stages of Rock Crushing:
An important component to deciphering the optimal equipment for rock crushing is the stage of rock crushing. The first stage is referred to as the primary crushing stage. This stage involves taking a large, coarse piece of material and breaking it down. The result is typically material that is around four to six inches and can fit into a secondary crusher. The next stage is the secondary crushing stage, which takes the smaller pieces from the primary stage and breaks them down further. The last stage, tertiary crushing, takes the material output from the secondary stage and breaks it down into the finest material. The main idea here is that the materials in the primary crushing stage will start out much larger and by the tertiary crushing stage, they will be more of a sand or dust product.
The Jaw Crusher:
A common type of crusher is a jaw crusher, which is typically utilized to break down rock and other coarse materials. The jaw crusher is also referred to as “rock breakers” due to its level of force. This force allows this type of crusher to be used as the primary crusher for projects. The typical output from this machine is a dust or sand-like material. The small size of this machine also makes it convenient for tight spaces that other crushers cannot reach. Mining companies will utilize this tool due to its efficiency and ability to fit into smaller, tight areas.
The Two Main Types of Jaw Crushers:
The two primary types of rock breakers are a double-toggle and a single-toggle. The double-toggle works with an overhead pivot movement. This model is efficient and does well working with abrasive, tough rocks. The single-toggle is a more compact version of the double-toggle design. These machines typically allow a slightly smaller feed size than the double-toggle model and often experience a bit more wear on the parts. For longevity of the machine, the double-toggle may serve as the better option, but the single-toggle can still get the job done and worn parts can be easily replaced.
The Mechanics of the Jaw Crusher Machinery:
As with most machinery, different designs will operate differently, but the central concept is the same across models. These machines work through compressive forces to break down large rocks into smaller pieces. The machine has a jaw with a stationary surface and a swing surface that passes down on the rock. The rock will stay within the jaws until it is small enough to fit through the back gap. The smaller product that exits the machine can then be transferred to a secondary crushing machine to produce an even finer product.
The Roller Crusher Machinery:
Another common type of crusher is the roller crusher. This type of crusher is another compact force crusher similar to the rock breaker. It works by using two rollers that are connected to each other and placing the rock in-between them to roll through and therefore be crushed. Due to the size of this machine, it is typically used as a form of secondary crushing for rocks. The output product from this crusher machinery is small gravel-like material. There is really only one type of roller crusher and it is best suited for smaller rocks and materials between four and six inches. Once again, the product of the roller crusher can be transferred to another tertiary crusher machine to obtain a finer result.
What is a Gyratory Stone Crusher?
The gyratory crusher has a similar setup to that of the jaw crusher. This machine uses eccentric compressive forces to crush rock and other material into small components. Unlike the rock breakers, the gyratory crusher can also be utilized as a secondary crusher in addition to a primary crusher, depending on the desired outcome. This machine works by putting rock into a top chamber and enters a spinning grinder at the bottom. The rock is squeezed and grinded down until it is small enough to fall through the bottom.
How is a Cone Crusher Used for Crushing?
Cone crushers are another style of compression crushing similar to those above. Due to the power of the cone crushers, tough, abrasive materials like granite are best suited for this machine. Materials are pushed through these machines by squeezing them, until they are broken into various smaller pieces. The basics behind the cone crusher are a multi-system pulley set-up that adds in room for mechanics. The most modern cone crushers produce a more cuboidal product that can resemble products from impact crushers.
How does an Impact Crusher Differ From a Compression Crusher?
Unlike compression crushers, impact crushers are best used for materials that are less coarse and abrasive. A common material for impact crushers is limestone. Materials are broken down with an impact crusher by placing it into an anvil or hitting it with a low bar. An impact crusher is typically used after material has already been processed through a primary crusher. Similar to the cone crusher, this machine produces a product that is a finer consistency and a cuboidal shape. Impact crushers are the most cost-effective option for machine crushers and produce a sand-like material.
What is a Composite Crusher for Rock Crushing?
A composite crusher is used to process materials and extract elements. These machines are often used for sandstone and cement. Composite crushers are energy efficient and simple to use. Materials inserted into this machine are raw materials that extend from timber to stone. This can be used as a primary stage machine and is typically used for broken furniture and breaking down large timber and logs.
How to Maintain the Overall Efficiency of Crusher Machinery:
A new crusher machine works wonderfully, but it is normal for the machine to wear down over time. Despite this, there are steps to take to keep up with the efficiency of machinery. As with any type of machinery, regular inspections should be made to ensure that the machine is working properly and there are no loose or broken parts. When working with impact crushers specifically, it is imperative to keep a watchful eye out for the hammer and rotor. These components are vital to the machine’s function and should be kept up for optimal performance. A cone crusher requires additional maintenance and precautions. The mantle and concave are primary components of the cone crushers and should be inspected prior to the use of this machinery. Materials entering a cone crusher should be kept dry and should be fed into the machine evenly to maintain proper performance. Finally, for sand-making machines, including impactor crushers, it is vital to regularly lubricate the rotor and impeller for the most efficient result.
Protective Measures From OSHA for Participant Safety With Rock Crushing:
Proper safety measures should take place when using any type of crusher, compressive of impact. Silica is a common byproduct of rock crushing that can be dangerous for human inhalation and can result in serious health effects. Several control measures should be taken to prevent the amount of silica released in the air and inhaled by those working with crusher machinery. In order to suppress the amount of dust produced in the crushing process, it is recommended to use water sprays and mists. For optimal operator protection from silica and production dust, the machinery operator should be in an isolated compartment that is supplied with fresh air and controlled exposure.
How to Minimize Dust Emissions When Working With Crusher Machinery:
The crusher operator should always work the crusher under the manufacturer’s instruction to prevent additional dust emissions. There are a few other steps that can be taken to prevent extra dust production. It is important to locate the nozzles on the machinery that is above the locations of dust emission. These nozzles should be placed in a position that adequately wets the area and material. Nozzles should provide complete coverage over the material, but the water droplets should not blow away from the site.
Concluding Thoughts in Regard to the Mechanics of Rock Crusher Machinery:
The first step to determining what rock crusher machine to use for a project is deciding which stage of crushing the original product is in. Very large, coarse materials are most likely in the primary stage of rock crushing. Smaller chunks that are a couple of inches are typically in the secondary crushing stage. Anything smaller than this is usually in the tertiary crushing stage. The stage of crushing the material is in, will then determine which machinery is most appropriate. Jaw crushers are one of the most common machines that perform well with primary materials that are tough and large in size. This is a compressive machine. Other compressive crushers include roller Crushers, gyratory stone crushers, and cone crushers. All of these use eccentric compressive forces to squeeze the rock into smaller pieces. To obtain a fine, sand-like result, it is recommended to use the impact crushers, which differ from compressive machines in that they use blunt force to break down the rock.
Regardless of the machinery that is used, it is important to take the appropriate safety measures. Silica is known to be harmful when ingested and measures should be taken to limit the exposure from rock crushing procedures. These measures include wetting the materials, following the manufacture’s directions for machine usage, and isolating workers when using the equipment. When safety questions arise, it is necessary to contact OSHA for further information.
Crushing machinery is useful across several domains from construction to breaking down lumbar. With knowledge of the mechanics, an appropriate machine can be selected to obtain the desired result.