Roller conveyors are a great solution for your material handling needs. They are a sound choice for both transportation and accumulation of cartons and come in two basic frame styles: rollers set high (RSH) and rollers set low (RSL). These terms refer to the vertical position of the carrying rollers relative to the side frame. Although the RSH frame design has been Hytrol’s default standard for many years, the RSL design offers many distinct advantages in applications within a conveyor system.
What are RSL and RSH?
The standard configuration for an RSH conveyor is to have a 6-1/2” tall frame with 1.9” diameter carrying rollers. They are called RSH because the top of the roller is positioned 1/4” higher than the top of the conveyor frame. The RSL frame is designed with the frame to be 8-1/2” tall while maintaining the same position of the roller from the bottom of the frame. This allows the taller frame to extend 1-3/4” higher than the top of the roller, therefore, the rollers are set lower in relation to the top of the frame.
BENEFITS OF ROLLERS SET LOW
Simpler and Quicker Installation
The RSL configuration offers distinct advantages during the installation process, particularly when installing a conveyor equipped with EZLogic® controls. An RSH design must have the reflector and accumulation kits, which are both shipped loose, mounted to the frame during the final field install. The RSL design has the accumulation photo eyes, wiring and reflectors fully integrated into the side channel, therefore, TOTALLY, eliminating field mounting of these component assemblies. This equates to reduced time required for the mechanical installation team.
In short, RSH conveyors ship with some assembly required while the RSL products ship factory ready.
Reduced Installation Costs
Since the accumulation kit ships installed with the low-set rollers, labor costs are reduced because the workforce does not spend time uncrating, sorting parts, setting up, and installing the accumulation and reflector kits. Shipping space and costs are also less with RSL because there are no pallets required for the accumulation and reflector kits.
Easier Guardrail Installation
The low-set rollers come designed with a built-in guardrail that is sufficient in most floor or mezzanine-supported applications. When a taller rail is needed, installation is made easier with RSL by simply bolting the channel or angle guardrail to the top flange of the conveyor frame. There are additional savings because the purchased guardrail will be 2” shorter due to the conveyor itself containing some built-in rail.
More time is required in mounting a fixed channel guardrail to RSH frames because spacers must be used to allow an opening for the accumulation photo-eye beam to see to the reflector. This means more components to handle, additional risks for mistakes, and more time required per foot for installation.
Improved Handling and Sensing
Thin and narrow cartons on RSH can catch under a guardrail that has been spaced up from the channels. Thin cartons also can wedge themselves into the reflector channel on RSH frames and cause a reflector to break. This is not the case with RSL. There are no accumulation or reflection channels for packages to wedge under or into. The set low roller frame also provides a more defined target for the photo-eye beam which improves sensing of cartons, particularly when conveying narrow cartons on wide conveyors.
Hytrol’s newly designed low-set roller side channels also feature flow tabs. A tab is designed into the end of the conveyor frames and can be pushed out slightly from the conveying surface on the infeed ends, creating a smooth transition from section to section. This prevents cartons from getting snagged on the conveyor ends and provides continued smooth carton motion down the conveyor line.
When to Select RSH
RSH are often required when picking to or particularly when pulling cartons from a conveyor; otherwise, operators must put cartons up and over the built-in rail. RSH also are required when spurring onto or off a conveyor with diverters or transfers.
When needed, the frames may be easily provided with frames for RSH on one side and RSL on the opposite side for optimal flexibility.
Use the RSL design whenever possible. This frame feature offers a great option that will cut down on your installation time and costs while providing improved handling and sensing of cartons; not to mention, it just looks good.