Keep MDRs Rolling

Motorized-drive roller (MDR) conveyors have come a long way since being introduced to material-handling industries. The days of loud, clunky systems that were complicated to set up and run are gone. Modern MDRs are quiet, energy efficient, and simple to operate. According to Ray Kozlowski, director of service and support for Milwaukee-based Hilmot (hilmot.com), these systems are also easy to maintain.

Today’s MDRs are designed to keep pace with manufacturing and distribution centers that operate around the clock—sites that can’t afford critical conveyors to go down, for any length of time. Such situations are less of a worry where proper inspections and preventive maintenance (PM) procedures are regularly performed.

As with other systems, the key to keeping MDRs up and running is preventing problems from occurring or catching them before they become major issues. The right way to do this, Kozlowski stated, is to establish an inspection and maintenance schedule that coincides with PM checks of other machinery in your facility. He offers the following tips.

Inspect these items weekly (at a minimum).
The rubber O-bands that loop between MDR rollers are common wear items. (They’re what move the rollers and propel packages and other items along the conveyor.) Much like tires on a car, O-bands deteriorate and occasionally need to be replaced. Visually inspect them for signs of wear, cracks, frays, or loss of elasticity.

Inspect other mechanical components to make sure everything is tight, in place, and serviceable. These inspections should include:

• checking MDR roller speeds, and readjusting as needed
• checking strip and full-width belts on belted-zone conveyors for proper tension and tracking, and adjusting as needed
• checking divert pins, timing belts, and hardware, and replacing as needed
• checking support legs and guard rail for stability
• checking end plates, divert mechanisms, and carrier rollers.

Inspect the MDR electrical system to make sure components are clean and free of dust. These inspections should include:

• checking drive cards for proper function
• checking photo eyes, and adjusting beam path as needed
• checking that system LED lights are green, not red
• removing covers on power-supply enclosures and blowing clean air through them to remove dust and debris.

Manage parts and tools to minimize downtime.
It’s a good idea to keep a bench stock of common replacement parts. In addition to O-bands, consider stocking electrical components, since it can be difficult to predict when they might fail. Typical items include:

• drive cards
• power supplies
• motorized rollers
• photo eyes.

A basic set of tools will suffice when performing preventive maintenance on MDRs. Your tool set should include:

• 3/8-in. drive ratchet and sockets
• matching wrench set
• standard flat-tip and Phillips screwdrivers
• terminal screwdrivers
• wire stripper
• channel-lock pliers.

Stay abreast of best practices.
To aid in the inspection and maintenance process, some MDR manufacturers offer instructional how-to videos on YouTube and elsewhere. They can be an important resource for your plant. After all, adhering to best-practice inspection standards and catching (and dealing with) issues before they become bigger problems is an effective approach to keeping your MDR conveyor—and facility—rolling along. MT

—Jane Alexander, Managing Editor

For more information on motorized and conventional conveyor systems, including questions about their maintenance, visit hilmot.com or email rayk@hilmot.com.