How To Eliminate Hydraulic Problems: Engineer Them Out

Sept. 8, 2014
It's always a good idea to engineer out potential problems if you can. If you don't use an oil to water heat exchanger, cooling water can never contaminate the oil. If you don't install pump intake isolation valves, the pump will never be started with the valve closed. And if you don't paint the inside of hydraulic tanks, the paint can never come off.

A large part of being smart in any area of expertise comes from doing your homework. And this is especially true with hydraulics. Here's a story from one of our readers which illustrates this point pretty well:

"I'm fairly new to hydraulics and I thought coating the interior of a hydraulic tank I'd made with a zinc spray (cold galvanizing in a spray can, like paint) would be a good idea. The idea was fine but the reality was not so good. I had no way of predicting that the components of the oil would dissolve the zinc coating... I'm fortunate that there is little I can do at this point that would further endanger my soul."

Call me superstitious, but I'm not a fan of painting the inside of hydraulic tanks, period. To digress for a moment, it reminds of a client a few years back who had a machine with a history of the oil to water heat exchanger failing and contaminating the hydraulic system with water. He asked me what he could do about the problem. When I suggested switching to an oil to air heat exchanger, there was a long pause on the other end of the phone. Followed by: "Why didn't I think of that!"

Here's the thing: engineer out potential problems if you can. If you don't use an oil to water heat exchanger, cooling water can never contaminate the oil. If you don't install pump intake isolation valves, the pump will never be started with the valve closed. And if you don't paint the inside of hydraulic tanks, the paint can never come off.

Oh sure, all of these thing can be done in such a way that the risk of the worst case scenario happening is minimized. You can specify a double-walled oil to water heat exchanger. You can install proximity switches and interlocks on pump intake isolation valves. And there are paints specially formulated to withstand contact with the myriad of different hydraulic oils out there. Although as far as I'm aware they don't come with a guarantee. Like I said, the worst case scenario is minimized, but NOT completely eliminated. The risk remains.

And why should you need to paint the inside of a hydraulic tank anyway? Think about it for a moment. How many other hydraulic components are painted internally? None. Zilch. Nada. So why don't these components rust? Because the hydraulic oil is formulated with rust inhibitors.

But the hydraulic tank is different, right? I mean water settles to the bottom and air circulates in the top. Well, make sure the tank has a drain point - and see that it's used. And if you install a desiccant breather, rust on the inside of the tank's air space will be minimized, if not eliminated.

And so what if a bit of light surface rust forms on the inside of the tank anyway? Aside from not looking real pretty how bad can it be? It will likely make a small contribution to contamination load, but the system's filters will soon take care of this.

I've designed and built hundreds of hydraulic power units. And never painted the inside of a single tank. In some instances, I've actively discouraged it. I've also worked on many hundreds more built by others. And I'd guesstimate less than two percent of those had the inside of their tanks painted - some successfully and some not.

Either way, I'm yet to see any evidence that leaving the inside of a hydraulic tank unpainted is detrimental to the system. But as this hydraulics user found out the hard way, painting it can be. Especially if you don't do your homework first!

P.S. on the subject of homework, "Six Costly Mistakes Most Hydraulics Users Make... And How You Can Avoid Them!" is essential reading. And it's available for FREE download here.

About the Author

Brendan Casey Blog | Author

Brendan Casey is a war-weary and battle-scarred veteran of the hydraulics industry. He's the author of The Hydraulic Troubleshooting Handbook, Insider Secrets to Hydraulics, Preventing Hydraulic Failures, The Definitive Guide to Hydraulic Troubleshooting, The Hydraulic Breakdown Prevention Blueprint and co-author of Hydraulics Made Easy and Advanced Hydraulic Control. And when he's not writing about hydraulics or teaching it, Brendan is flat-out helping consulting clients from a diverse range of industries solve their hydraulic problems. To contact him visit his company's Website:
www.HydraulicSupermarket.com

Continue Reading

Handbook Simplifies Advanced Aspects of Mobile Hydraulic Controls

May 10, 2017
Author Brendan Casey lays out his hydraulics know-how that he acquired over 27 years in a simple handbook made for people that want to improve their skills in troubleshooting ...

Kidney loops: They aren't just for hydraulics any more

Sept. 1, 2004
When was the last time you changed the oil in your refrigerator's compressor? That was a question posed to me by Ken Stofen of Racine, Wis. The answer, of course, is never, and...

Sponsored Recommendations

MONITORING RELAYS — TYPES AND APPLICATIONS

May 15, 2024
Production equipment is expensive and needs to be protected against input abnormalities such as voltage, current, frequency, and phase to stay online and in operation for the ...

All-In-One DC-UPS Power Solutions

March 13, 2024
Introducing the All-In-One DC-UPS, a versatile solution combining multiple functionalities in a single device. Serving as a power supply, battery charger, battery care module,...

Motor Disconnect Switches

March 13, 2024
With experienced Product Engineers and Customer Service personnel, Altech provides solutions to your most pressing application challenges. All with one thought in mind - to ensure...

DC Power Solutions: Streamlined Power Supplies for Every Need

March 13, 2024
CBI All In One UPS Power Solutions combine the requirements for several applications in just one device which can be used as power supply unit, battery charger, battery care module...