How to properly maintain conveyors?

Are normally used to transport soiled dishes into the dishwashing room and most conveyor belts today are constructed with molded snap-on slats composed of a low-friction poly carbonate compound. This design makes it possible to replace an individual slat rather than the entire belt.

The slat-type belt can be designed to make curves around corners or columns. Some conveyor belt consists of a single, continuous piece of material composed of flexible polyester fabric cords. The conveyor is provided with a drive assembly housing, which contains a motor that controls the operation of the belt.

Some units also have a belt- washing system located in the housing. The belt-washing system automatically sprays water and (sometimes) a detergent on the belt to keep it clean. This system can operate while the conveyor is running, or it can be turned on at the end of the operating period to clean the belt.

The design of the conveyor returns system and the type of belt vary from manufacturer to manufacturer. The slat-type belt normally has either an angle-return system supporting each side of the belt or a monorail return unit supporting the belt from the underside of the slats. The solid-type belt’s return system consists of a series of rollers upon which the belt rides.

Maintenance of Conveyors –

On conveyors provided with a solid-type belt, the belt may start to travel to one side after a period of use. This condition results from one or more factors whose effect does not become evident immediately after the belt is put into use for the first time. If the problem is not corrected, however, the edge of the belt may become frayed. To retract the belt, perform the following steps:

1. If the belt is drifting toward the right side-as you look toward the tail end (loading end) of the conveyor-move the right-hand bearing on the tail shaft back. If the belt is drifting forward the left. Side, move the left-hand bearing on the tail shaft back.

2. If the belt fails to respond to the action taken in Step 1, the nose pulley, the snub pulley, the drive pulley, or the return belt idlers may be out of alignment. Check them to make sure that they are at exact right angles to the longitudinal axis of the conveyor.

If it becomes necessary to replace a section of belt, be sure to use only Model metal or stainless steel lacings will rust and contaminate the belt. Using a square as a guide, make a clean cut across both ends of the belt. With a gauge pin set in the lacing and with the belt lying flat on a firm surface, use a hammer to drive to prongs of the lacing firmly down into the belt.

The construction of the slats for a slat-type belt differs from one manufacturer to another. Consult the manufacturer’s literature before removing and replacing a slat. Some slats are connected by stainless steel pins; others snap onto a stainless steel chain. In replacing a slat, always use a slat that is identical to the type provided with the conveyor originally.

Some conveyors are provided with an automatic belt washer. The system includes a solenoid valve, a manual shutoff valve, an adjustable mixing valve, and spray jets. The belt washer will not operate unless the conveyor is running. A detergent injector is also available with this system.

A pump is installed in the water line downstream from the solenoid valve. The pump should not be allowed to run dry, and operating personnel should make sure that the detergent tank is refilled; the detergent does not travel through the pump, it will be necessary to prime the pump.

Ask the supplier about the proper type of detergent to use with your equipment; the wrong type of detergent can cause damage to the belt or to the washing system. Only detergent of light viscosity should be used.

The drive chains should be kept snug at all times. To adjust conveyors that have a torque-tamer mounted on the idler jack shaft, it will be necessary to loosen the jack shaft pillow block bearings and move the shaft downward until the chain to the conveyor of shaft is snug.

Making sure that the shaft is still parallel to the conveyor shaft, retighten the pillow block bearings. This adjustment will not make the drive chain from the motor to the torque-tamer tight; to do so, loosen the motor mounting bolts and slide the motor back until the chain is snug.

Then retighten the motor back until the chain is snug. Then retighten the motor mounting bolts, and the adjustment will be complete. Consult the manufacturer’s literature before making any adjustment to the drive chain, since the procedure can differ with each manufacturer.

The electrical control panel varies with each manufacturer, too. Consult the manufacturer’s literature and wiring diagrams before performing any service on the control panel. Some conveyors are provided with a variable speed motor, to avoid damage to the drive unit, never turn or adjust the speed control knob unless the motor is running.

The primary preventive maintenance required by the conveyor is cleaning of the belt and lubrication of the system. High-pressure lubrication is not recommended, because it can break the grease seals of the bearings. Only enough pressure should be applied to produce a thin bleeding of grease between the seal and the bearing collar.

Preventive Maintenance Schedule lord belts – Daily:

» Clean the belt in accordance with the manufacturer’s recommendations. » Check the detergent tank, and keep it fully loaded.

Monthly:

» Lubricate the spur gear, the bevel or maître gear, and the roller chain drives after every six months:

» Check the oil level of the motor gear box. Provide oil in accordance with the manufacturer’s recommendations.

» Check for leaking seals on the motor. Replace any such seals.