In the first part of this blog I went on a bit of a rant about waste and how one can so easily save tens, if not hundreds, of thousands of pounds a year just by paying attention to better control systems.

Hydraulic pumps are another area where the application of relatively inexpensive control systems can yield great results. Typically hydraulic pumps work on a cycle with a pump to build pressure on oil to move a cylinder and a valve dumping the oil back into the tank to allow movement. A side effect of this is to transfer heat from the motor and pump to the oil that then needs to be cooled. Again, it is typical that the pump is running throughout the cycle ‘ because that is how it has always been done’.

Now that technology costs are more accessible it means sophisticated controls are available for even the smaller pumps. It may seem obvious that major savings can be gained by switching the pump off when it isn’t doing anything but that hasn’t been widely recognised yet except on the larger and more capital-intensive units. I recently carried out such an installation at a plant in China that controlled the speed of the pump slowing it down to a stop as it reached the required pressure and spinning it back up when pressure was required.

This type of situation is often the result of companies having been sold a standard engineering solution that appeared to be a money saver but ignored their particular needs. A ladder manufacturer I visited recently had been sold a completely unnecessary Inverter to ‘save’ energy on their power pack. The fact that demand was always at its maximum, so switching off and on was not an option, was ignored. There is no saving to be made in that situation.

Another where there was a real saving was in the press operated by an Apple juice processor. Here the press was idle for much of the time while loading or unloading was going on and not at its full workload until the final stage of juicing. The power pack could easily be switched off for much of the time. This hadn’t been done because it was not easy to do manually and resetting it was often problematical. I proposed an automated control system that would handle this and delivered excellent performance and energy saving.

The truth is that each situation needs to be seen and understood in situ. Avoiding paying for something you don’t need is sometimes blindingly obvious but what to do about it sometimes less so. Checking it out always pays dividends and can be achieved without massive disruption to the core processes

   
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