Comprehensive Guide to Selecting the Right Conveyor Belt for Crushing and Screening Operations
Selecting the right conveyor belt for your operation is critical. Replacing conveyor belt can be an expensive task that can bite into your profit margins via costly downtime and expenditure on service teams and replacement products. This article seeks to help you understand the intricacies of choosing the right belt up front, so you can effectively communicate with your conveyor belt suppliers, and focus on doing what you do best.
Conveyor Belt System Components
A deep understanding of the system’s components is essential for selecting the right belt:
- Head Pulley and Drive Mechanism: Essential for driving the conveyor, often roughened to increase traction.
- Tail Pulley and Tensioning System: Facilitates belt cleaning and maintains optimal tension.
- Idler Rollers: Support the belt and load, preventing sagging and misalignment.
- Conveyor Carcass and Covers: Provide tensile strength, lateral stiffness, and protection from environmental and operational wear.
When ordering your belt, you’ll often be quoted the belt using a code that designates the belt grade, length, width, carcass material, breaking strength, ply and top/bottom cover thickness and the grade. For example, a textile belt might be marked as “EP 630/3 6/2 M”, indicating a polyester carcass, 630 kN/m minimum breaking strength, 3 plies, 6 mm top and 2 mm bottom cover thickness, with a grade M cover. Similarly, a steel cord belt might use “St 1600 7T/5 X” showing steel cords, 1600 kN/m strength, 7 mm top and 5 mm bottom cover thickness. Cover grades vary for specific applications like heat or chemical resistance. The specifics are listed below:
Belt Grades and Material Specifications
Conveyor belts are classified into grades that reflect their resistance to abrasion, cuts, fire, and static. Understanding these grades is pivotal:
- N Grade: Offers moderate abrasion resistance for general use.
- M Grade: Higher resistance to cuts and abrasion for handling sharp, heavy materials.
- F Grade: Designed to resist fire hazards in combustible environments.
- E Grade: Features anti-static properties for explosive atmospheres.
- S Grade: Ensures resistance to slippage, ideal for steep inclines.
Ply, Length, and Material Composition
The choice of ply, length, and material composition is dictated by the operation’s specific requirements:
- Ply: Indicates the belt’s layers and affects tensile strength and impact resistance.
- Length and Width: Determined by the size of the system and throughput requirements.
- Material Composition: Varies from rubber, PVC, polyurethane, to steel cord, each selected for specific operational needs and environmental conditions.
Identifying Signs of Conveyor Belt Wear and Tear
With a better understanding of how your conveyor belt is constructed, its now critical to understand its operation within your conveyor. Early detection of wear and tear can prevent costly downtime and replacements. Preventative maintenance is key here to limiting impact on your belt. Key impacts on your belt over time include improper operating tension, product load or power load being modified without consideration for belt type and changes to your crushing material. Further, matching the conveyor width with pulleys and adjusting the belt length and tension in response to changes in operational demands are crucial steps in maintaining optimal performance. Broader inspections on your conveyor rollers / idlers and how it tracks through your conveyor are equally important. A cheap roller filled with dust can quickly result in premature wear in specific areas or worse, a tear. Equally, if the belt isn’t tracking correctly, you will often find wear and tear at the edges of the belt which can quickly degrade the entire belt. With preventative maintenance in hand, there are some specific factors that should be considered for selecting the right belt for your operations.
Selecting the Right Belt for Your Operation
Environmental Conditions
The operational environment plays a pivotal role in selecting a conveyor belt. Often, N Grade belt is perfectly suited to standard crushing operations. However, for environments prone to fire hazards, F Grade belts with fire-resistant properties can be key. In areas where static electricity poses a risk, especially in explosive atmospheres, E Grade belts with anti-static properties are necessary. Additionally, consider the temperature range within the operation area—some belt materials are specifically designed to withstand extreme temperatures, whether hot or cold, without degrading. For example, ACBG as a conveyor belt company, has a range of EPDM and Nitrile composite belts for specific applications such as asphalt trucks that provide strong heat resistance as well as protection from oils and greases.
Abrasiveness and Material Composition
The nature of the materials being conveyed significantly impacts the choice of conveyor belt. Materials that are abrasive or sharp may require belts with high abrasion resistance, such as M Grade belts, to prevent premature wear and tear. The weight and size of the materials also dictate the belt’s required tensile strength and thickness. Heavy or bulky materials necessitate a robust belt with a strong carcass to support the load without stretching or breaking.
Ply Consideration
The ply of a conveyor belt—referring to the number of layers of material making up the carcass—directly influences its strength and flexibility. Operations handling heavy or sharp materials might need a belt with more plies to ensure durability and impact resistance. However, more plies can also mean less flexibility, so the specific application’s needs must be balanced.
Length and Width Adjustments
The conveyor’s length and width should be tailored to the operation’s throughput requirements and spatial constraints. A wider belt can handle more material, improving efficiency, but requires a stronger motor and more support. The length of the belt affects tension and load distribution, necessitating adjustments to ensure smooth operation.
Material Composition
The choice of material for the conveyor belt affects its performance and longevity:
- Rubber Belts are versatile and durable, ideal for a wide range of applications, including abrasive materials handling.
- Steel Cord Belts are chosen for their high tensile strength, suitable for long-distance conveying of heavy loads.
- PVC Belts offer good fire resistance and are suitable for environments where this is a concern but are not typically employed in crushing operations.
- Polyurethane (PU) Belts are preferred in food processing or pharmaceutical applications for their hygienic properties.
Throughput Requirements and System Configuration
The desired throughput rate dictates the belt’s width and speed, ensuring efficient material movement without overloading the system. The configuration of the conveyor system—whether it includes steep inclines, sharp curves, or long straightaways—also influences the selection. Belts designed for inclines, for example, might have cleats or high-grip surfaces to prevent slippage.
Durability and Maintenance Considerations
Selecting a belt that balances initial cost with durability and ease of maintenance can optimise long-term operational costs. Belts that are easier to repair or replace, or that require less frequent maintenance, can significantly reduce downtime and maintenance expenses.
Professional Audit and Consultation
Given the complexities of selecting the appropriate conveyor belt, seeking professional advice or conducting an audit can provide clarity. An audit identifies current and potential future challenges, guiding the selection process toward a belt that enhances efficiency, reduces downtime, and controls operational costs.
Conclusion
The selection of a conveyor belt for crushing and screening operations is a nuanced decision with implications to your bottom line. By combining a thorough understanding of conveyor belt wear and tear, system components, grades, ply, and material composition, operations can make informed choices. This holistic approach ensures the selected conveyor belt not only meets the operational demands but also contributes to the overall success and sustainability of the operation, enhancing operational efficiency, safety, and profitability.
ACBG is on the leading conveyor belt suppliers and we stock a wide range of conveyor belts. Our team of in house experts are always happy to talk to you about your material handling requirements. We also provide wholesale belting by the roll to specific customers that utilise a large quantity of belting in their operations.
