Insane Hydraulics

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Hydraulic Maintenance Negligence Example

No matter how long I work with hydraulics and how many situations defying common sense in most unbelievable ways I come across - I'll never say "Now I've seen it all!" since there will always be someone willing to challenge the current champion of the "industrial ignorance" race...

Some years ago I was asked to "take a look" at a malfunctioning tree stump removing machine (don't even remember now what the hydraulic problem was, only that it was one of those "solved on the spot" ones), and as I was driving away from the "ground zero", pleased with the work that went well, a large truck parked along the road caught my eye. The front of the truck was damaged pretty bad as if something very heavy had smashed into it. When I asked the operator, who was taking a ride with me, about what had happened, he told me this amusing tale, proving yet again that boundaries of ignorance would never be discovered!

The story went like this: a heavy wheel loader was one of the many machines regularly used in that enormous homestead that consisted mainly of steep hills - so the machines often had to work on inclined terrain. And everybody knows - heavy machinery plus uneven ground is a dangerous mix unless efficient and reliable braking is present.

The loader, like any respectable machine of that size, was "armed" with two independent braking systems. One of them was an active, foot-controlled brake, powered by a gear pump and equipped with a pair (for extra reliability) of bladder accumulators to store hydraulic energy for braking in emergency engine stall situations, and the other was a parking disc brake, that locked the transmission when activated. The whole system was supposed to be bullet-proof, but, of course, NO system in the world is fool-proof...

I got to see the loader a couple of hundred yards down the road. A simple glance at the machine from a distance would make you think "you poor thing..." and gave you the desire to put it out of its misery. It looked like the whole "service business" had been completely discarded, with multiple oil and other work fluid leaks coloring the rusty frame with cheerful dust powdered spots. The whole picture spelled "abandonado", and according to the man it had been like this since as long as he could remember...

The story went on - coming to the part where the parking brake stopped working properly due to oil leaks and was dismounted to "get rid of the problem". You heard me right - dismounted, i.e. physically removed from the machine! Some credit must be given to the logics though - "no part - no malfunction" - how can you argue with that?! And who needs a parking brake when you can simply lower the front blade onto the ground, anyway?

The next thing "to go bad" was the active brake accumulators - first one, then the other. One day the engine stalled when the loader was on a relatively flat surface and the operator noticed that it suddenly "lost brakes"! A mechanic was consulted over the phone, and his word was to throw away the old accumulators and replace them with new ones. The damaged accumulators did go to scrap, as advised, but instead of installing new accumulators, the pipes were simply plugged (because the accumulators were expensive). The service procedure was rescheduled for future (better) times. The machine seemed to be braking just fine when the engine was running... Naturally, to address the issue of safety, the operators were advised to "take extra caution". How very proactive!

Of course, along with the hydraulic system, the poor diesel engine was also kept maintenance-virgin, and one day it stalled due to the completely clogged fuel filter exactly the moment the loader began descending a steep hillside... There was no steering - for it would take two Schwarzeneggers from "Commando days" to steer an articulated frame without assistance. There was no parking brake (we got rid of that, remember?) There was no active braking. There was no control of the front blade - the pilot pressure pump was not working, and, oh yes, the pilot pressure accumulator had been long gone, too. Attempts to start the engine were futile - no fuel could pass through the clogged filter. The machine slowly but surely started to accelerate downhill, proving once again that gravity is the one basic force that can't be turned off. The driver saw his life pass before his eyes, made peace with God, and bailed out of the two-meter elevated cabin of the runaway wreck. Eventually, the loader was stopped by the large truck that was parked at the bottom of the hill. Luckily, the "bailee" was not killed or injured.

According to the operator, it was not the first time this happened! Only before that, the slopes weren't that steep and the fuel filter that clogged, so the engine would eventually start before the "ejection" point. All of the operators had refused to work with the machine except for that fearless fellow, so the loader was kept in service until that day...

As much as I sympathize with hydraulic machinery owners who apply doubtful maintenance practices (it's them who keep us in business, remember?), I still believe that life-threatening brake-tampering situations should be avoided at all costs! Machine owners, please, do not let your machinery come to this! If you feel the compelling desire to threaten the lives of your employees, you should check in a mental hospital as soon as you can, for this is not normal! If you do not want to provide your hydraulics with adequate service, consider contracting someone who will!

If you are not an equipment owner but work for a company with such negligent practices, this is a big problem, and I see only two ways it can be addressed: either this is a great career opportunity if you invest in your hydraulic education and convince your boss to implement a preventive maintenance program supervised by you (read - get a better pay-check and save your company some cash), or this is a textbook career dead-end, which means it's time for you to start looking for new employment ASAP because most likely this company will always treat you the same way they treat their hydraulics - like crap. Don't worry, whichever you choose to do - it's a win!