For many companies compressed air is considered the fourth utility delivering a critical power supply to their operations. It can also be a very expensive utility if it is not well maintained, resulting in; elevated energy costs, unplanned downtime – and depending on the application – even product spoilage. However, there are a number of ways you can ensure that your compressed air system operates reliably, efficiently and at its optimum. This includes following the OEM’s recommended maintenance schedule, using only genuine spare parts and selecting only authorised Service Technician’s to carry out maintenance work. Additionally, performing the OEM’s recommended daily and weekly maintenance checks is another very simply practice that will also assist you in operating your compressed air system at its peak performance.
An example of daily and weekly maintenance checks
Here’s an example of the daily and weekly maintenance checks that KAESER Compressors recommends are undertaken on a KAESER ASK T Sigma Control Basic belt driven rotary screw compressor with integrated refrigeration dryer as described in more detail in the attached YouTube video;
On a daily basis;
- Check the compressor display
Check the display on the compressor controller for any relevant information such as service due messages or warnings, and carry out tasks punctually. In addition, listen for any unusual sounds.
On a weekly basis;
- Check belt tension
To ensure long component and service life, it is important to check the tension of the drive belts. Drive belts need to be tensioned to their optimum design tensions to avoid slipping and premature wear of drive belts and pulleys.
Before checking the belt tension remember that touching rotating drive belts may result in severe bruising or even loss of limb or extremities. The cabinet should not be open while the machine is switched on. Therefore, prior to checking the belt tension, ensure that the supply power isolator is switched off and locked using a safe lock out/tag out procedure, and check that no voltage is present. Allow the machine to cool down.
Check the belt tension and adjust as necessary. The tensioning device uses spring force to apply correct tension to the belts. Adjust the tension when the marker pin reaches the top of the elongated hole. Loosen the locking nut. Use the adjusting nut to adjust spring tension until the marker pin reaches the lower end of the elongated hole. Tighten the locking nut. Turn the pulley by hand so that all of the belt can be inspected for damage. Damaged belts should be immediately changed. Contact your compressed air service provider if the belts require changing.
- Check the cooling oil level
Most air compressors are designed to have a certain volume of oil circulating. If this volume decreases the internal temperature will increase which will ultimately lead to the compressor overheating and shutting down. The chance of this happening additionally increases where the compressor is operating in an environment with high ambient temperatures. The result would be premature wear as well as unplanned service requirements and downtime.
The sight glass allows a risk-free reading of the cooling oil level. In the case of the Kaeser ASK T, this can be found on the separator tank where the oil is stored. The oil indicator should be fully filled with oil when the machine is at standstill. However, the correct oil level cannot be seen at standstill. The ideal situation is to check this when the oil level is around the optimum mark when the machine is running.
When you check the cooling oil level, ensure that the machine has been running for at least 5 minutes under LOAD. As soon as the minimum level is reached, replenish the cooling oil.
- Cooler: check the filter mat
The filter mats help to keep the cooler clean. If the filter mats are clogged, adequate cooling of the components is no longer ensured.
To check the filter mat, first make sure the machine is switched off. Carefully remove the filter mat from the retaining frame (no tools are needed to remove the filter mat). Beat the mat or use a vacuum cleaner to remove loose dirt. If necessary, wash with lukewarm water and household detergent. Change the filter mat if cleaning is not possible or if the change interval has expired. Carefully insert the filter mat in the retaining frame.
- Control cabinet: check the filter mat
A filter mat is placed behind every ventilation grille. Filter mats protect the control cabinet from ingress of dirt. If the filter mats are clogged, adequate cooling of the components is no longer ensured. In such a case, clean or replace the filter mats.
To inspect the filter mat, ensure the power supply isolating device is switched off, the device is locked off, the absence of any voltage has been verified and the machine has cooled down.
Carefully remove the ventilation grille and take out the filter mat. Beat the mat or use a vacuum cleaner to remove loose dirt. If necessary, wash with lukewarm water and a household detergent. Change the filter mat if cleaning is not possible or if the change interval has expired. Insert the filter mat in the frame and latch in the ventilation grille.
- Check the condensate drain
Condensate is an unavoidable by-product of air compression. If not reliably drained off at all collection points, the resultant corrosion can cause costly downtime and damage to the compressed air system.
Condensate drains should open automatically when enough condensate has collected. To check that the drains are working, first ensure the machine is shut down and the Power LED lights. With one hand, lightly touch the condensate drain hose at the condensate drain. With your other hand, push and hold the <> key at the condensate drain for at least 2 seconds.
As soon as the condensate drain opens, you will feel a short burst at the condensate drain hose. If you do not experience a burst, the condensate drain will need servicing.
- Log all maintenance tasks completed
Finally, document all maintenance and service work completed. This enables the frequency of individual maintenance tasks and deviations from the OEM’s recommendations to be determined.
Before completing daily and weekly maintenance tasks
When working on a compressed air system remember that compressed air is contained energy. Uncontrolled release of this energy can cause serious injury, or death.
The example above is for a specific compressor make and model. Whether you are undertaking daily or weekly maintenance tasks for this specific compressor or another, before any maintenance tasks are performed, it is important that you only allow qualified and authorised personnel to perform the daily / weekly maintenance tasks that have read, are conversant with and adhere to the safety instructions and section of the service manual applicable to maintenance of the piece of compressed air equipment. In addition, the relevant statutory and accepted regulations should be observed.
Information correct at time of print.
The information provided in this blog and video clip are for guidance only and refer to a specific compressor make and model. Only qualified and authorised personnel should perform daily / weekly maintenance tasks that have read, are conversant with and adhere to the safety instructions and section of the service manual applicable to maintenance of the piece of compressed air equipment.