Inspection of Single-Point Lubricators

GREASOMATIC lubricators extend conveyor life

Automatic lubricators have become an accepted method of lubricating critical pumps, conveyors, fans and blowers in manufacturing facilities today. These remarkable devices provide a number of benefits including improved worker safety, reduced production downtime, and extended equipment life to name a few. But while they offer these benefits and do their job with little to no user interaction, they still need to be periodically inspected.

Why inspect?

Periodic inspections help to ensure that your automatic lubricators are effective and working properly to meet your performance expectations. This is especially important after the initial installation. You may find that by injecting a small amount of fresh grease at regular intervals, you will need less amount than when manually lubricating with a grease gun. Inspection becomes even more important if the single-point lubricator will be exposed to an adverse environment.

Environment – Exposure to water, high or low temperatures and vibration can have unfavorable effects on a single-point lubricator.

  • Water

    – Exposure to direct sunlight, rain or snow, equipment wash-down or wet manufacturing environments can cause problems if the moisture gets into the internal electronics. Protective covers should be used.
  • Low Temperatures

    – The base-oil viscosity increases with exposure to colder temperatures. This reduces the flowability of grease and can cause a single-point lubricator, depending on the design, to dispense reduced volumes of lubricant or stop dispensing altogether. Be sure to know the operating temperature of the lubricator prior to installation.
  • High Temperatures

    – Elevated temperatures can cause the oil to separate from the thickeners in some greases. This separation can create a blockage in lube lines and in the bearings.
  • Vibration

    – Vibration can also cause the oil to separate from the thickeners and create blockages. In addition, high vibration can damage internal components in some single-point lubricators.
  • Location

    – It is important that single-point lubricators and connected lube lines be installed in a protected area. Lube lines can become damaged, interrupting lubricant supply to the lube point. Lube lines can also work their way loose from a fitting if the connections are not secure, so they should be regularly checked.

Who should inspect?

These inspections should be done by personnel who are familiar with the type, operation, and the check function of their lubricators.

Types & Operation – there are basically three types of single-point lubricator:

  • Spring-Loaded

    – These units operate by using a compressed spring to push the grease into a lube point. These lubricators have been around for decades but over the years have been superseded by more advanced and more reliable lubricator technology.
  • Electrochemical

    – These lubricators rely on a chemical reaction to generate a gas at a controlled rate. As the volume of gas increases, it pushes on a piston and dispenses the lubricant into the lube point.
  • Electromechanical

    - There are a few different designs of this type of lubricator. Some, like the MEMOLUB®, have a positive displacement pump design that dispenses a metered amount of lubricant at a controlled rate. Others operate very similar to the electrochemical type, only instead of using gas they use a mechanical drive to advance the piston to dispense the lubricant. Both sub-types of electromechanical lubricators can be battery or externally powered.
Inspection of Single Point Lubricators

What should you inspect?

When inspecting single-point lubricators in the field, here are some areas to check:

  • Lubricant Reservoir

    – You should always check the lubricant level of the single-point lubricators. Most types have visual access to the lubricant reservoir. If the single-point lubricator is set on a long dispense rate, it might not always be apparent that it is dispensing lubricant because the piston is moving at such a slow rate. One “low tech” way to verify the lube level is decreasing is to put a hash mark on the housing each time you make your inspection.
  • Lube Lines

    – Check to ensure the lube lines are not damaged or crimped, and that they are still attached. If you see lubricant pooling near the Single-Point lubricator or at the lube point, it is a good indication there is leaking.
  • Visual Indicators

    – Some lubricator types have blinking lights or LCD screens that indicate the electronics are functioning correctly. Other types use more reliable mechanical means to verify operation. The MEMOLUB®, for example, has a check function where you simply depress any one of three contact pins located at the base of the lubricator to test-cycle it.

How often should you check?

The recommended frequency of inspection is based on several factors, including:

  • The critical nature of the equipment

    – Often single-point lubricators are installed on critical pieces of equipment and should be inspected on a regular PM schedule.
  • The lubricator dispense rate

    – If the single-point lubricator is set to dispense lubricant over a 1 to 6 month period it should be inspected on a weekly basis. If the single-point lubricator is set to dispense from 6 to 12 months, it can be scheduled at a longer time interval.
  • Comfort level

    – After the initial installation of the single-point lubricator you should check them on a regular basis. As you become familiar with how your single-point lubricator works and begin to trust its reliability, you can adjust your schedule accordingly.

Summary

Single-point lubricators have been widely used for years to reliably and economically lubricate industrial equipment all over the world. And technological advancements have made them more versatile and dependable than ever. Of course, the greatest risk in using them is failure to inspect them. So, the take-away here is that they should be inspected regularly just like any other piece of equipment.

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