Conveyors and automated storage and retrieval systems can elevate the performance of your distribution facilities, improve safety and significantly reduce labor costs.

Conveyors can move everything from lightweight cartons to heavy pallets throughout your warehouse and they are an essential component of contemporary material handling design.

Conveyors are classified in three separate divisions for most material handling operations:

• Powered roller or belt systems (for package handling).
• Powered roller or chain conveyors (for pallet handling).
• Non-powered conveyor systems

Powered Package Handling Roller or Belt Conveyors

Powered roller or belt conveyor systems are frequently used for smaller pieces like packages and cartons.

Conveyor belts are usually employed for advancing cartons along a line, while rollers are used for amassing cartons in certain areas along the line.

Belt Conveyors

In use since the early 1900's, belt systems are an indispensable piece of many material handling configurations. Lower cost than roller conveyors and frequently better suited to certain tasks like advancing lighter weight products, belt systems are used in many material handling designs.

Conveyor belts employ a long, looped belt that is positioned on the top of a metal slider belt substructure or an array of non-powered rollers. Motor driven pulleys turn the belt and move items down the conveyor line.

Conveyor belts can be configured with a range of surfaces and materials depending on the function and role of the conveyor. For instance, a belt surface could be un-ridged in segments where products need to glide off the line and may have a gripping surface on segments where goods must be moved up inclines.

Roller Conveyors

Despite the long and successful history of belt conveyors, newer roller systems offer a host of more useful benefits in many modern material handling uses.

Most importantly, roller systems can allow for accumulation of items on the line where belt conveyors can not. This is an important distinction because there are endless scenarios where objects must hold and accumulate in material handling configurations. Accumulation is often necessary when objects must be paused before being relayed to automated palletizers or sorters.

Advanced roller conveyors also have the ability to supervise products on the line and utilize zero pressure accumulation, meaning none of the amassed objects come into contact as they slow down and finally stop.

Roller conveyors are made up of numerous cylinder rollers that are generally set up in one of these ways:.

• Line-shaft conveyors: in a line shaft system, a long metal rod runs underneath the rollers at a right angle to them and is attached to each roller with rubber O-rings. A drive mechanism spins the shaft, and consequently turns the rollers via the attached O-rings. Line-shaft conveyors are the most cost efficient of all roller style conveyors, but they also require the most service because the connections between the rollers and the shaft need frequent readjustment and often break.
• Belt-driven roller conveyors: As you may expect, these systems are driven by a belt that sits beneath the roller surface. A motor propels the belt, which propels the cylinders.
• MDR conveyors: Motorized roller conveyors, frequently called motor-driven roller (MDR) systems, are built in sections where a single cylinder from each segment is propelled by it's own drive mechanism. That one powered roller is linked to the adjacent rollers in that section via flexible O-rings, thereby rotates all the cylinders in the segment. MDR segments are placed in sequence to create the conveyor line.
  MDR systems are known for their energy efficiency because: a.) they generally are powered by 24 volt DC motors and b.) the motors can be configured to engage only when an object is present on the rollers, meaning they are idle most of the time.
  Although the cost of MDR conveyors is higher than belt drive and line-shaft rollers, electricity costs and maintenance outlays are usually far lower than the other options mentioned.
• Segmented belt conveyor: the principle of motor driven roller systems ultimately begat the development of segmented belt conveyors. Similar to MDR systems, segmented belts are powered individually and offer several of the same advantages of motor driven rollers, including accumulation potential.

Powered Pallet Handling Conveyors

Powered pallet-handling conveyors are frequently used with automatic palletizers and AS/RS setups. Pallet handling conveyors can usually accommodate gross weights of up to 2 tons and operate at a far slower rate than carton handling conveyors, many times at speeds of just a few pallets per minute.

Pallet-handling conveyors come in a couple of varieties: chain conveyors and roller conveyors.

• Pallet-handling chain conveyor: perhaps the simplest of all conveyors, pallets on a chain conveyor line sit directly on two or more lengths of heavy duty chain. Motors propel the lengths of chain which in turn advance the pallets along the line.
• Pallet-handling roller conveyor: somewhat like MDR conveyors, pallet handling roller conveyors use large cylinders and heavy duty chains to connect the motorized cylinder to the remaining rollers in a conveyor unit.

Non-Powered Conveyors

Skatewheel or roller systems are the conventional types of non-powered conveyors used in material handling. These types of systems use inertia and gravity to advance smaller loads though warehouses, pick modules, workstations, automated sorters, loading docks and package sorting areas.

Skatewheel systems are comprised of numerous independent wheels and need very little power to sustain the inertia of products as they advance along a conveyor line. In general, they propel items quicker than non-powered roller configurations and they have more versatility when it comes to configuration. Given that they're individual wheels as opposed to a belt, they are often applied in curved segments of a conveyor system.

Typically non-powered roller conveyors are not as expensive as skatewheel conveyor systems. They are frequently used for work stations, pick modules, and other zones where it's beneficial to maintain a flat platform to perform tasks. They also slow products down that are coming from faster moving mechanisms like sorters so that human laborers can keep pace with system output.

Non-powered systems have a significant disadvantage as compared with powered conveyors: by employing inertia and gravity to move materials you lose the ability to control the force applied to those items. Put another way, you don't have control of the speed and inertia of items on your conveyor line.

Conveyor System Engineering In Tucson

If you 'd like a full analysis of conveyor system possibilities for your warehouse, DC or other material handling operation, you can talk to a professional at Raymond West by calling (520) 729-4222.

Service Area:
Tucson, Oro Valley, Marana, Sahuarita, South Tucson, Green Valley