Why also if winter doesn’t challenge your viscosity of hydraulic oil, it still isn’t the finest season because that hydraulics.

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Should the seasons of the years matter to a hydraulic system? That most likely depends whereby you room in the world and also what kind of state the device is in. Extreme temperatures like those in Siberia or northern Canada will certainly test equipment to the limit both in their style and likewise their state of maintenance.

Because of the global market because that hydraulic equipment and not always knowing wherein your OEM kit can end up, we thing extreme cold should always be top top the designer’s agenda.

So in ~ what temperature does oil freeze? If low temperature hydraulic fluid has no been used, you could well find that the ambient temperature is below the pour suggest of the oil and also it is solid. The pour point is once the oil merely goes solid and won’t pour. Well prior to then, it will certainly have become steadily more viscous, potentially allowing the system to not prime properly and be starved the lubrication. 


For years, we have used the Lee commodities hydraulic oil viscosity chart on http://www.leeimh.com/images/p146_graph.gif and http://www.leeimh.com/images/p147_graph.gif (see below).

It is in Fahrenheit, however it is invaluable. You’ll check out some hydraulic fluids yes, really become really viscous an extremely quickly together temperature drops. Hydraulic oil viscosity is other you simply need to be on top of. Now look at Skydrol aerospace hydraulic fluid and this is remarkable at short temperatures, as exactly you would certainly hope if the hydraulic undercarriage of your Airbus is down at -40 degrees C up at 10,000 metres. If anybody states “low temperature operation” to you, constantly find out exactly how low they room talking about! You can look at equivalent viscosities on other everyday fluids to acquire a “feel” or a comparison. We have run a pump in ~ room temperature on a viscous fluid to replicate using it on an additional oil at short temperature, however over the years have likewise soaked a unit down to -20 degrees C in a trusted cold room to test it.


So what rather happens come hydraulics at low temperatures other than having to operate on viscous oil, assuming a heater has not to be fitted come the reservoir? Seals can be too brittle to job-related in the cold weather. The viscosity will certainly make rams slow and also pumps struggle. Nothing forget the issues of needing to operate devices in gloves to avoid warmth burn.

Come back to the UK and we room pretty happy people. Us rarely need to see the temperature ferris wheel that room seen even a few hundred mile to the east or north of us. The swing between summer and also winter in the UK is significantly less than quite a few other areas of the world.

So currently the nights are illustration in, what are the threats for winter hydraulics in the UK?

Yes, reduced temperatures mean more viscous oil and harder seals. Perhaps the UK climate is much more forgiving ~ above the temperature front, yet we do live in a damp and soggy country. Include in a few of those Atlantic storms sweeping in and also we would certainly focus very first on obvious hydraulic shortcomings then relocate on come weatherproofing.

What would we do?

1) Hoses and also couplings.

Check for damaged hoses and also leaking rapid disconnects. Honestly, they perform only have a limited life. Readjust them to suit you quite than struggling in the cold and also dark.

2) Cylinders

Get that weeping lamb sorted. Maybe a bearing U-seal has actually been damaged and weeping for ages, however lower temperatures might just do it fail altogether.

3) Reservoirs4) Filters

Swap out any type of filters that are overdue or gaining near the red sector on the clogging indicator. Need to you risk equivalents from a one stop shop or initial equipment? We market the Sarum Hydraulics MX collection stainless filter units and also can offer cost effective replacement facets from stock. Over the years on various other equipment, we have always used original Hydac and also MP Filtri elements for purchase in filters.

5) Motors

If you have any kind of motors or valves that space tripping out and also troublesome, get an electrician in and also find out what the problem is.

6) Weatherproofing

Check weatherproofing. Replace damaged covers, glands and also housings. In fact anything that could let the weather in.

7) Compressors

And we recognize it is non-hydraulic, however is the compressor in its outside enclosure up to speed? Is the weather proof? If water it s okay in to the electrics, the is a disaster. Space the pneumatics functioning properly? If there is a press switch, make sure it is cutting the end correctly. Was it serviced during the an excellent weather? Clogged filters or dirty oil will cut the life of her compressor.

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Overall, us reckon that you don’t desire breakdowns on mobile plant and forced maintenance outside in the winter if you missed the opportunity to sort it in the autumn.