Home>Handbooks>Maintenance Management Guide>Give your hydraulic and electrical systems a health check

Give your hydraulic and electrical systems a health check

17 June 2014

Electrical and Hydraulic Systems need regular check-ups in order to maintain peak operational performance. Paul Hickman, an expert in drive technology at Bosch Rexroth, says that all-too-often end-users neglect to give these vital pieces of equipment the TLC they deserve.

Drives, motors, hydraulic power packs and actuators are too easily forgotten until something goes wrong. This reactive approach to maintenance and servicing fails to predict problems and leaves industry at the mercy of production downtime, much of which can be easily avoided.

To be fair, some industries are better than others. The print industry, for example, is usually a very close monitor of its drive and motor equipment because downtime is exceptionally costly. An hour’s lost production of a national newspaper will usually mean the printer picks up the entire cost of that nights print run.

This approach to Hydraulic System and Electrical drive maintenance and servicing needs to be embraced much wider. I would recommend an annual or at least bi-annual health check for a Hydraulic and Electrical System, ideally as part of a preventive maintenance programme. This regime of regular checking should include external sensors and couplings for damage and visual checking for signs of clogging and leakage with filters, valves, pipes and hoses, cylinders and heat exchangers.

The exterior of a drives cabinet will often offer the first clue to the overall health of a panel. In particular, the chilling unit can show evidence of where the buildup of heat is slowly damaging the drive technology. For example, plastic trunking distortion or a blocked air filter can potentially be an indication of panel overheating or that too many cables have been squeezed into a confined space.

It is also important to check the physical connections of all drives, motors and power supply units for adequate installation and condition. Typical problems include trapped encoder signal wires or cables with clamps or glands missing. It is not uncommon for example to find cabling routed through a door aperture which has become kinked. This may sound minor, but a trapped cable wears much quicker through the external insulation allowing coolant or other media to ingress.

One of the most obvious signs of neglect or irregular cleaning and maintenance can be a build of dust in the cabinet. Dust is the enemy of temperature control and a small increase in temperature, which could be directly attributable to a blocked filter, will prematurely degrade electronic components. Blocked intake filters, for example, restrict air flow to the drive fan making it work harder and increasing the possibility of the drive overheating.

Temperatures within the panel should also be checked. This can be done in one of two ways, either with remote temperature monitoring via infra-red temperature guns or through the use of self-adhesive, maximum temperature storing thermometer strips. These strips can be used in different areas of the panel to gauge the air circulation levels or any condensation issues which can affect the electrics.

Similarly, it is important to check the temperatures within the main drives using thermal imaging photography of main drives enclosures. This can help identify further faults, such as loose connections or excessive heat within the drive which can cause fire.

Hydraulic and Electrical Systems and all the associated components are vital pieces of equipment, but all-too-often they are forgotten about and given little thought until something goes wrong.

The reality is that, with a little more care and attention, uptime can be dramatically improved and catastrophic and costly downtime avoided.