Different Types of Flat Belt Conveyors
Flat belt conveyors are what most people think of when they picture a conveyor system. They have a full take up assembly that routinely manages the belt tension using a counterweight and bend rollers.
When a flat belt needs maintenance or repairs, there are several different things that can be done. One of the most popular is to use modular plastic belt segments.
Conveyor Belts
Flat conveyor belts come in many shapes and sizes. Some are designed to be able to transport products around corners, while others can even take on incline or declines. They are built to suit the environment they will be working in, with different covers that can resist heat and fire, or even chemicals.
Most manufacturers build them to fit their industry, with the belt itself typically made from a composite of lengthwise polyester and crosswise polyamide threads. The combination of these two types of threads give the belt a high tensile strength-to-weight ratio, excellent flexibility, and great resistance to impact and chemical damage. The belt is then covered in a durable plastic, or in some cases a more sturdy fabric.
The flat belt rests on carrying straight rollers or a flat sheet slide bed complete with structure and supports. It is often driven at the head pulley and discharged at the tail pulley, which reduces the wear on the belt.
Some flat conveyor belts are fitted with vertical cleats in their design, which can be used to keep loose materials secure on an incline or decline. They can also be used to ensure consistent spacing between items or to help with metal detection. Other add-ins can be attached to the belt, including trip cords along the side and safety start-stop buttons.
Magnetic Pulleys
Magnetic head pulleys are the perfect solution for the continuous, automatic removal of damaging tramp iron from any flat belt conveyor. They can be retro-fitted into existing conveyor systems or built in during the original conveyor design. They work by utilizing powerful magnets to capture and adsorb the tramp ferrous metal from the product before it can cause damage to subsequent machinery such as grinders, shredders, mills, or pulverizers.
Magnetic Head Pulleys can be powered either by a permanent magnet or by an electromagnetic coil. The permanent magnet versions provide a deep magnetic field and are ideal for nail, screw and bolt-sized tramp metal recovery. The electromagnetic designs are used for applications that require a less intense, but high-intensity magnetic field such as fine iron particles and stainless steel scrap.
They can be incorporated into almost Flat belt conveyor any conveyor system to help protect against metal contamination that would otherwise cause expensive equipment damage and production delays. They are especially useful when combined with overhead Magnetic Crossbelt Conveyors for deeper burdens and maximum separation in heavy-duty applications.
Magnetic head pulleys are available in a variety of diameters, working widths and shaft types to suit a wide range of application requirements. They can be manufactured with standard ceramic or rare earth magnets in a choice of styles. These include herringbone, chevron, or radial pole designs. They can also be equipped with vulcanized rubber or stainless steel lagging to reduce the risk of physical damage.
Crowned Head Pulleys
Crowned head pulleys are used as the driving pulley on conveyor systems to help with belt tracking. The idea is that the center of the head pulley is made a little larger than the edges, and when the belt runs onto the pulley it will be carried around the center without slipping. This concept works well with steel belts, as they tend to have higher tensile strengths laterally than rubberized fabric belts.
The problem with this system is that it will not work on high modulus bulk haulage belting. These belts will not flex enough to conform to the crown, which will lead to excessive tension in the belt, leading to splice and carcass failure. It is recommended that crown pulleys are only used on low stretch belts and in applications where tracking is of prime importance.
Another way to track a belt is by using a radial or trapezoidal profile on a roller or pulley. These profiles generate steering forces that will offset any lateral force and keep the belt centered. This is not a good solution for troughed conveyors, however, because the profile will have to be sized very precisely to match the width of the trough idlers.
The best method of ensuring accurate belt tracking is to ensure that all pulleys, snub rollers and carrying idlers are square with the frame and parallel with each other. This will prevent the belt from contacting the wrong surfaces, and it will also allow for maximum power transmission.
Conveyor Rollers
The rollers that support a conveyor belt are not only vital to its function, but also a key component in the overall design of a conveyor system. They vary in size, shape and material to accommodate different loads and environments.
Conveyor rollers can be made of steel, stainless steel, rubber or plastic. The materials of choice depend on the weight, impact and conditions of the load to be moved. Steel rollers are Flat Belt Conveyor Manufacturer durable, low-cost and easy to clean. They can be coated in rubber or plastic to increase friction and improve load retention. Rubber rollers are anti-static, chemical resistant and customizable to fit your specific application. They provide increased capacity, quiet operation and reduced noise.
Rollers that are used in conjunction with a pulley are known as tension or return pulleys. They are solid pulleys that are designed to withstand high forces, and they are often found near the drive pulley. They may be curved or have a smooth metal surface.
Wing pulleys are another type of return pulley that works with the drive pulley. They are shaped like a wing and help to clear material from the conveyor belt, increasing efficiency. They can be smooth or ribbed to add grip and are typically found in environments where the conveyor is constantly cleaning itself. They are also good for reducing traction problems.