Why McLanahan Inclined Vibrating Screens?
McLanahan’s MAX Series Vibrating Screens are designed to meet and exceed the demanding applications and specifications required of screening equipment. MAX Series Vibrating Screens provide a solution for all heavy-duty applications, including minerals, aggregates and more.
Capable of separating coarse feed material from finer materials, these vibrating screens are a low-headroom design. Each screen is built with maximum strength steel to withstand heavy loading and with the durability to give you longer wear life. MAX Series Vibrating Screens are available in a range of sizes from 6’ x 16’ (1.8m x 4.8m) to 8’ x 24’ (2.4m x 7.3m). They are designed to fit into any existing structure and operation with no rework. Backed by McLanahan’s years of industry experience, we work with each customer to make sure their MAX Series Vibrating Screen meets the specific requirements of their application.
MAX Series Vibrating Screens were designed with operator safety in mind. Side plates feature cross beam inspection ports that allow you to inspect the inside tubes for failures when the tube is not visible due to abrasion-resistant lining, thus eliminating the need for operators to crawl between decks for inspections. Foreign material that can corrode or abrade the inside of the cross members and cause premature failure can be flushed out via cross beam inspection ports. The eccentric mechanism features jacking bolts in the mechanism tube to support the eccentric shaft during bearing change-outs, eliminating the need for a crane to suspend the shaft or the chance of the shaft tipping over and injuring workers, creating a safer work environment and decreasing downtime.
Many of the features of the MAX Series Vibrating Screen improve maintainability for increased uptime. Independent cross members allow you to replace only worn tubes and not the complete deck frame. The direct drive system eliminates the requirement for a pivoting motor base to keep belt tension on startup, which can be troublesome to maintain and eventually fail over time. Speed can be adjusted by simply replacing the motor sheaves and can be varied from 700 to 900 rpms without a change to the driven sheave.
The MAX Series Vibrating Screen is designed to be durable for the longest useful wear life and with maximum strength steel to withstand heavy loading. Side plates are a fully bolted construction that reduces/eliminates crack propagation due to stress risers in the steel caused by welding and provide the ability to quickly replace worn components without cutting. The eccentric mechanism is a custom one-piece machined eccentric shaft for maximum strength and force output. It features a labyrinth seal to deter oil contamination and eliminate the need for a standard breather, which is prone to plugging and failure. The quick change spring kit allows the removal of the spring pack with only minimal vertical clearance and no overhead crane required. This saves the customer money, as well as reduces downtime and increases worker safety while changing out the springs.
How Inclined Vibrating Screens Work
In an Inclined Screen, the vibratory motion is circular. Vibration lifts the material, aiding stratification, while the combination of vibration and angle of incline provides the travel speed of the material over the deck.
Screens are used throughout material processing to separate and size material prior to and following crushing stages. At the primary stage, large scalping screens remove fine material before the feed enters the primary crusher, helping to protect the crusher’s wear parts from abrasive stone or sand material that has already been sized. Without scalping, the primary crusher’s liners wear down faster, requiring more frequent changes and maintenance downtime.
Following the primary crushing stage, screens with two or three decks and different opening sizes are used to separate the material into different size categories, with conveyors transporting the sized material for further crushing or for stockpiling as a saleable product. Usually this screening is accomplished through dry screens. Wet screens may help to remove debris from material before stockpiling, as clean stone is often required for concrete and asphalt specifications.
Depending on the process stage, the material to be screened is fed to the screen either from a loading device such as a wheel loader (intermittent feed) or from a hopper or conveyor (continuous feed). The screen box vibrates via shafts with counterweights or exciters, causing the material bed to vibrate as well.
Benefits of McLanahan Inclined Vibratory Screens
- Replacement cross members are shorter with machined and matched shims to allow easy installation in areas with limited clearance
- All shaft components on the eccentric mechanism slide onto the shaft, allowing for easy removal and installation of replacement parts
- Jacking screws on the motor base make belt tensioning easy
- Side plates utilize A572 Grade 50 plate as standard, giving them a 45% higher yield strength than traditional A36 plating
- Available in a range of sizes from 6’ x 16’ (1.8m x 4.8m) to 8’ x 24’ (2.4m x 7.3m)
- Designed to fit into any existing structure and operation with no rework
- Backed by McLanahan’s years of industry experience, service and support
Frequently Asked Questions
What is the best combination of stroke and speed for my application?
The following chart will help you determine the appropriate stroke and speed.
Does it hurt my screen to run it backward or uphill?
The reason you might run the screen uphill is to slow the rate of material travel, increasing the amount of time the material stays exposed to the deck, providing better odds of the material falling through. Running the screen uphill also changes the exposure of the particles to the openings themselves. Quite often the choice of running a screen uphill is made in finer screening applications where efficiency can be tough.
You will not do any harm to the screen or the mechanism itself by running it uphill. Just make sure you do not increase your bed depth too much or you will have a negative effect rather than a positive one.