Companies looking to replace long repetitive runs of products through facilities often end up looking at conveyors to reduce costs and improve efficiency. What type of conveyor you choose depends largely upon the application, space and budget. Your facility would likely utilize more than one type of conveyor, and knowing what type is best for each application means a great deal in the bottom-line efficiency of your application.
A motor-less conveyor is a very cost effective product that allows gravity to do the work of moving product from one point to another. This type of conveyor is often used to feed boxes and pallets to an awaiting trailer at a dock. There are two popular types of motor-less conveyors: the skate-wheel and the roller conveyor.
A skate-wheel conveyor is good for longer runs and curves. The independently spinning wheels allow the product to make turns without sliding off of the edge of the conveyor. Since they are essentially shaped like the old steel wheels that used to be on our roller skates of old, the contact area is minimal with your product, allowing it to maintain better speed and cover greater distances.
A roller conveyor allows for better control of a product with regards to speed, allowing it to slow the product down if it is coming out of a high-speed sorter. A roller conveyor costs less, and its ample surface area makes it a good choice for pick stations.
One of the primary draw-backs to gravity-reliant systems is the inability to control the speed and force with which your products are being carried. If your product is fragile or expensive, these types may not be the best choice for your application.
Powered conveyor systems are most popular when product control is important. It allows products to be sorted and sent to many sections of your facility at varying speeds. It can also be used to transport products to higher levels in your facility, such as mezzanines or storage platforms.
A belt-driven conveyor employs an AC or DC motor to drive a looped belt. This belt typically has rollers or unfinished steel sheets to provide product support. If space is an issue in order to move product to higher levels, belt conveyors can be formed into a spiral conveyor system, minimizing its footprint but at a greater cost.
Sliding bed systems consist of an unpainted metal surface sliding along a bed. A sliding bed system may be the best choice if you need to move unstable loads at a slow speed. Used to transport small products and odd-shaped items, they can be found in assembly stations and load stations.
A live roller conveyor is similar to a gravity roller conveyor with one distinction--it uses motors to drive the rollers. Powered roller conveyors fall into a number of different categories, depending on the way the rollers are driven. Three common categories are line-shaft, belt-driven and motorized rollers.
Line-shaft conveyors use a long metal shaft that runs below the bed of rollers. Rubber o-rings connect the rollers to the shaft so that when the motor turns the shaft, the shaft turns the rollers. A line-shaft conveyor is the least expensive type of roller conveyor.
Belt-driven roller conveyors are driven by a belt. The belt runs underneath the roller bed, and as a motor moves the belt, the belt moves the rollers. A belt-driven roller is a good accumulator, because it’s easy to create zones. You can drop the belt away from the roller in any zone where you want to create an accumulation of product.
Motorized rollers section the motorized roller conveyor into small, divided zones. One or more of the rollers in any given section is motorized, which moves product. The rollers in each zone are connected to each other by rubber o-rings so that the turning of the motorized roller turns all the rollers in the zone.
Live roller systems like these are ideal for applications using heavy product with a flat surface. By building these types of roller conveyors into “zones,” it is easy to control speed and allow them to run only when product is recognized, saving energy, money and reducing noise. In addition, it allows for product accumulation, releasing product when it is needed, further enhancing productivity.
Zero pressure accumulation allows products to be transported, stopped and started without ever touching each other. This is important for fragile or expensive products. Minimum pressure accumulation allows a pre-determined amount of contact, without enough force to cause damage. This allows more through-put while minimizing product damage.
Powered zone conveyor systems like the ones listed above are being utilized by more companies to better control product, conserve energy and money, and improve ergonomics.
Pallet-handling conveyors are commonly used with automatic palletizers or automated storage and retrieval systems (AS/RS). There are two types of pallet-handling conveyors: chain conveyors and roller conveyors. Both handle heavy loads and are relatively slow, typically handling just four pallet loads per minute.
Pallet-handling chain conveyors use motors to rotate up to four strands of heavy-duty chain. The pallets ride directly on the chain. A chain conveyor is less expensive than a roller conveyor, and it’s best suited for captive systems where pallets are a uniform size and in good condition.
Pallet-handling roller conveyors are similar to roller conveyors used for handling packages, but the rollers are wider and thicker. Most pallet-handling roller conveyors are driven by a chain.
Chain-driven pallet conveyors use a chain that runs along one side of the roller bed. Each roller is connected to the chain with a sprocket. The conveyor is divided into small segments, and each segment has a motor, allowing for some accumulation of pallets.
Partnering with a company like Cardinal Integrated System to survey your application, listen to your goals, and engineer and install a system that works for you is key to getting the most out of your conveyor system. Give us at call at 410-344-1801.