Conveyor Belt Cleaners That Clean Better & Last Longer: Aiming for Safety & Success in the Load Zone
A bulk material handling facility will routinely process tons of products each day. Supplying and transporting the material can lead to operational challenges with that much volume, especially in the load zone. Better conveyor belt cleaners and solutions can be applied for resolving conveyor belt spillage and carryback.
This discussion will review what a conveyor belt is, how problems develop around it, and how they can be addressed with the right conveyor belt cleaning solutions.
What Is a Conveyor Belt?
The conveyor belt provides the path and the means to transfer bulk material and the force required to move it, typically along a horizontal plane. Vital to the production of bulk material handling, the belt is one of the conveyor system’s most expensive parts. It is chosen for its needed properties in handling material, such as belt width, strength, tension, corrosion, and impact resistance.
The most common conveyor belt design is when the belt wraps around a pulley at either end. The pulley at the head of the conveyor belt is usually coupled with a drive unit that moves the belt and transfers the material.
With a conventional design, the drive unit’s power is supplied by a direct-coupled motor gearbox or a direct- or parallel-shift drive that operates the drum through a properly sized couple. The drive unit’s size and design are determined by what an operation requires for the conveyor belt to start up under a full load. For example, small or medium-sized conveyors often use a fluid coupling to ease start-up and transient operations. Large conveyors will often employ variable-speed drives.
Because a conveyor belt’s operating conditions are often rugged, the belt also depends on heavy-duty supporting components. These supporting components include idlers, rollers, and bearings to help its performance with massive loads that may also involve extreme hot or cold temperatures.
Spillage & Carryback
Material spillage and carryback are two prevalent problems on and around the conveyor belt. Consequently, operators often cite these issues as leading challenges in the load zone.
Spillage is material that falls off the conveyor belt into the immediate area, such as under the conveyor’s return side. It is a frequent cause of material loss and compromised products, both of which impact profits. It can also degrade equipment and create occupational hazards such as slips, trips, and falls.
Carryback is loose material that adheres to the conveyor belt after it has passed the discharge point, mainly if the material is wet, sticky, flaky, or fine. A deteriorating belt can produce carryback as well. Carryback commonly causes belt mistracking, premature equipment wear, and material build-up on the conveyor system’s structures and moving parts.
Both spillage and carryback can also release fugitive dust particulate matter suspended in the air. In addition to creating setbacks such as limited vision, equipment wear, extra housekeeping, and the risk of combustion, fugitive dust can become a significant health concern if it is frequently breathed.
What Are Conveyor Belt Cleaning Solutions?
Different, and better conveyor belt cleaning solutions can be applied for resolving conveyor belt spillage and carryback. The goal with each is to have belt cleaners that clean better while lasting longer. The solutions also should work with any belt size and speed for any bulk material handling industry and material.
Some operators might accept a certain amount of stray material during production. In these cases, a single primary belt cleaner might be mounted in one particular area, often at the head pulley.
Other operators will want to ensure the entire belt is as clean and unobstructed as possible. An optimal approach to helping prevent recurring material problems in the load zone is implementing a system that applies both primary and secondary belt cleaners.
A primary conveyor belt cleaner, also called a pre-cleaner, is mounted to the head pulley right below the material flow. It effectively removes larger chunks of matter that cling to the belt after unloading – often about 60%–70% of initial carryback.
While the primary belt cleaner or conveyor belt scraper clears much of the larger pieces, a third or more carryback can remain as bits and fines. Placed right past where the belt leaves the head pulley and possibly elsewhere along the belt, secondary belt cleaners scrape material that may pass the primary cleaner. This can often increase the cleaning system’s overall efficiency to more than 90%.
Primary Conveyor Belt Cleaner
A primary conveyor belt cleaner should be made of an enduring material such as urethane, which will act similarly to a metal blade–type scraper without metal’s risk of damage. The belt cleaner’s design should be compact and modular for versatile mounting, and its profile will provide a varying attack angle to reduce blade-edge bull-nosing.. A torsion tensioner will self-adjust to maintain consistent cleaning as the blade wears.
When the blade needs to be changed, operators should have the ease to remove one blade pin, pull out the worn blade, slide in the new blade, and replace the pin. Replacement blades should be available for high temperatures and chemical or abrasion resistance. If needed, operators should retrofit the blade to other cleaner brands as well.
Secondary Belt Cleaner
A well-designed secondary belt cleaner is a conveyor belt cleaner made of a lasting material such as tungsten carbide. It also will have flaps that ensure carryback slides away from the blade and does not build up. If a secondary cleaner is manufactured well enough, it might serve as a stand-alone conveyor belt cleaning solution if the bulk material is dry and fine.
A blade holder will keep the center of the scraper blade on the belt, which will help clean cupped or worn belts. The blade ends will push down for even pressure across the blade, which will arc into the center as it wears to maintain blade-to-belt contact. Torsion arm segments will let the blade conform to the belt and move away from obstructions.
In addition to tungsten carbide, the secondary belt cleaner’s scraper blade should be available in tri-layer, high-temp, dual-layer, ceramic-bead, and chemical-resistant rubber. A dual rosta joint tensioner or self-adjusting pneumatic tensioner will also absorb severe impacts.
Specialty Belt Cleaners
An operation’s conveyor belt cleaning solutions can incorporate specialty cleaners such as a motorized brush cleaner and a V plough.
The motorized brush cleaner uses rubber bristles to remove and prevent fines and residue on the belt, particularly in recessed areas that primary and secondary cleaners cannot reach. Motorized brush cleaners are active only when the conveyor belt is moving. An inline drive shaft and cleaner bar also allow easier sealing when the brush cleaner is installed in an enclosure.
The brush cleaner is equipped with either a one- or two-horsepower motor, depending on the operation’s requirements. The motor turns the cleaner opposite the belt direction for the most effective cleaning, particularly for belts with distinctive cleaning challenges, such as grooved, ribbed, and chevron belts.
When bulk material is pinched between the conveyor belt and the return pulley, it might cause the belt to break. A V plough can remove the material before the belt reaches the return pulley.
A V plough features a single rubber blade attached to the mounting pole at two points and a height-adjustment arm at a third point. A floating-blade design ensures the blade remains to ride on the conveyor belt. A wire safety cable also provides extra protection.
A Note About Skirting
Primary, secondary, and specialty belt cleaners help achieve cleaner, safer, and more efficient bulk material handling. Proper skirting is equally vital to this objective.
By fastening to the transfer point, often with clamps, conveyor belt skirting surrounds the chute and forms a seal by lightly pressing against the top of the conveyor belt. This helps contain dust and material that might otherwise escape.
The skirting also complements other factors such as the belt speed, idler placement, and trough angle in reducing spillage and fugitive dust. Its material is typically determined by its needed properties (e.g., soft rubber for fines, polyurethane for rocks, fire-resistant anti-static rubber for underground mining).
Benetech: Your Ally in Bulk Material Handling
Benetech is dedicated to safe, efficient, and profitable bulk material handling at your facility, including the critical facets of keeping your conveyor belt systems clean and reducing unscheduled downtime. Contact us to learn more about conveyor belt cleaners, conveyor belt cleaning systems, and complete conveyor solutions that clean better, last longer, and remove carryback for your operation. Call us at (630) 844-1300 to speak with a specialist. Benetech can help keep your conveyor systems running.