# Hydraulic system static discharge



## Bird dog (Oct 27, 2015)

QMED said:


> Good thing this was not a hazardous location...


May be it should be.


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## joebanana (Dec 21, 2010)

Obviously something wasn't properly grounded, or bonded. Was this equipment UL listed, and labeled, or "home made"?


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## MDShunk (Jan 7, 2007)

Weird. Maye just have some new braided jacket hoses made up. I might guess that will solve the problem.


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## Wirenuting (Sep 12, 2010)

Yes I've seen that before. 
Branded and bonded units with a large collection tank for the filtered oil before its returned to the point of collection. These units were outside the hazardous location. The system refill lines used lower pressure, lower volume to refill the collection tank. 
Some of these filters were the cyntrifacle type and spun at high speed.. 
Good oil gets dirty and never truly gets destroyed when used for lubracation.


Go ask the "Oil King" about his unit.


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## micromind (Aug 11, 2007)

Conductive hoses should be used when static discharge is an issue.


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## QMED (Sep 14, 2016)

Looked through McMaster today didn't see any hydraulic hoses that specifically mentioned being conductive or anti-static or whatever. Plenty for dry food, wet food, fuel, water and all kinds of other materials.


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## frenchelectrican (Mar 15, 2007)

You should try to run a exteral #6 green or bare stranded conductor outside of the hydrallic hose. sorta like a jumper to act line bonding.

Just look up any aircraft refuel or fuel truck bonding set up it will work the same way for your useage. that can really reduce the amout of static spark.

I have one of my customer have portable hydrallic filter pump and I rigged up with the #6 stranded conductor as above and use either jumper cable clamp or large spring loaded clamp. ( yes you can use water meter clamp for this too ) 

Most low pressure hydrallic hose do not useally have braided mesh inside of the hose ( depending on hose size ) but yes high pressure hose do have them.


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## Wirenuting (Sep 12, 2010)

frenchelectrican said:


> You should try to run a exteral #6 green or bare stranded conductor outside of the hydrallic hose. sorta like a jumper to act line bonding.
> 
> Just look up any aircraft refuel or fuel truck bonding set up it will work the same way for your useage. that can really reduce the amout of static spark.
> 
> ...


He’s aboard a ship. He runs the risk of creating a greater hazard. 





QMED said:


> Looked through McMaster today didn't see any hydraulic hoses that specifically mentioned being conductive or anti-static or whatever. Plenty for dry food, wet food, fuel, water and all kinds of other materials.


Before you attempt a McMaster or grainier buy, find the IPB for the gear your looking at. Order the parts required and not the parts you think might work.


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## Cow (Jan 16, 2008)

I'm with Wirenuting. 

How old is the equipment?

I'd be calling the manufacturer of the equipment and getting them to step up and make it right.


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## QMED (Sep 14, 2016)

I have the nameplate data but haven't had a chance to see if we have any documentation on it. They're all using the same unbonded hose. I'm sure the skids are a few years old at most but the nameplates didn't look too professional lol. I would not be surprised if this issue was never even thought of by whoever ordered/assembled these things.


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## Wirenuting (Sep 12, 2010)

@;


QMED said:


> I have the nameplate data but haven't had a chance to see if we have any documentation on it. They're all using the same unbonded hose. I'm sure the skids are a few years old at most but the nameplates didn't look too professional lol. I would not be surprised if this issue was never even thought of by whoever ordered/assembled these things.


Static loading of hydronic liquids is a known problem, we studied years ago. We had remediation in place to remove it for the equipment we used.

In your equipment, if it was issued as a shipboard component, look to see if field changes had been made deviating from the original design. 
Adding an external bonding wire may create a greater hazard to the ship or its personal. It will not reduce or eliminate the static charging that you see.

Here is a short explanation of what and why your seeing the static discharge.
http://www.machinerylubrication.com/Read/809/electrostatic-charge-hydraulic


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## QMED (Sep 14, 2016)

Yep that's it, I did some researching and it's just some off the shelf equipment. Hose is called Vardex and is not conductive at all.


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## Wirenuting (Sep 12, 2010)

QMED said:


> Yep that's it, I did some researching and it's just some off the shelf equipment. Hose is called Vardex and is not conductive at all.


So now the question becomes,
Is it a hazard that needs to be remedied?

If it’s not a hazard or does not change the chemical makeup of the oil being filtered I would just watch the light show. 
If you believe it’s a hazard or that the oil has been comprised, I would report it for review and repair. 

As far as we know, the type of oil your filtering and it’s special location calls for review by those above you. Milspec fluids aren’t like what we find out in town.


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## paulengr (Oct 8, 2017)

In oil and gas the hose material is nonconductive. The suction hoses are generally one wire or two wire and the support wires that keep the hose from collapsing take care of it.

Oil/gas service hose takes care of this kind of stuff. But in day pipes often you have to provide your own. Hydrocarbons (oils) are mostly nonpolar molecules so they are naturally insulators. Passing them through pipes naturally mechanically strips electrons off causing a static charge. The statement that bonding creates a hazard is false. It’s already moving the charge back to where it belongs through the air. The whole ship is already ground so bonding just does this in a controlled manner at vastly lower voltages and currents before it gets to millions of bolts and arcs.

Fighting ship codes and oil service hose costs, somebody cheaper out. I’ve dealt with ship codes and inspectors before. They have a fit with anything that doesn’t have their stamp but not everything does and you get two levels deep before you find out their codes are all a political hack based on an international ship code that basically says bribe the local inspector which is a little challenging in the US where that is cultural taboo. The code usually says effectively that it’s approved if the code inspector says it is, and the local code says it is if the international code says it is. Catch-22. I ran into this on fire stop. So I told the inspector his code references the international code and that code says it’s acceptable so would he accept. He said yes, so it’s approved. It just takes somebody to read English. See why the codes are a joke?


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