Hydraulic Winch Pump

[Team Idris]

I'm puzzled?

Alfred Murray sold me a 'winch set' back in 2006 with a pump that was said to be around 35 litre/min to match the milemarker typeR winch. ( It has been excellent )

We are just in the process of replacing this pump and the Parker part number is for a 25 cc/rev pump. Which works out at 75 litre/min at 3000rpm (normal mains electric motor speed at 50 Hz). 35 is nowt like 75, so are many folk running this higher flow?

I see First4x4 (now the milemarker agent) are selling 26cc/rev pumps on a rubber belt, so it probably is right.

I am amazed we get away with a 3/8" valve block even with 1/2" hose. It must be an over-generous valve block inside because it doesn't ssound like it's about to go supersonic.

[steve b]

25cc/rev sounds the right size for the type R motor , and indeed the std motor too, they are high vol motors .

......are you tempted to go to 3/4" hoses and valves now?

What volume is your tank ? and do you run a cooler ?

mmm hydraulics

cheers

Steveb

[Team Idris]

10 litre steel tank and no cooler. Which leads us to think it cannot be fundamentally unhappy, as we haven't seen steam coming from the pump or tank in the wet stuff? But I am glad I went for a tank strainer that was bigger than needed for a 35 l/min flow.

The oil looked milky with water, but isn't dark, even for oil that is a few years old, let alone over-worked oil. But I thought I would change it and check the pump at the same time, because we felt the pressure available at tick over had dropped off since it was all new. And sure enough there is pump wear that says we will have an easier time on winch-and-drive with a new one.

The winch motor is interesting as this class are rated to run at 250 rpm and peak at 350rpm. But at 100cc/rev it is doing rated speed at 1000rpm. At 3000 it is well naughty! So I had better stay at 2000rpm engine speed when winching from now on

I couldn't afford a hydraulic rear winch originally, but the front has been so good that when one came up in Goodwinches super sale at £400 I had to get one. It's bigger in frame being Kingone, but pulls as well as the R. Now we can really winch ourselves into trouble

[steve b]

Blimey , 10 litres is a pretty small capacity , but it clearly works . That's interesting to know - what would you say

your normal time is pulling at load and the interval between it and the next?

What grade oil (SAE no ) do you use ? mine is 46 running a gear motor front and occasional rear MM and 35 litres tank

the milky oil may be a result of condensation from repeated heating and cooling?

all very interesting

cheers

Steveb

[Team Idris]

Or I caught the breather with the pressure washer? I need a proper level glass so I can tell when the oil is going wrong.

Oil is ordinary hydraulic oil, which is 10 I think.

Even if we are on a punch for 15 minutes we can't be winching for more than 5? And if the oil is acting as a thermal battery, you can count the mass of the motors and the body they bolt too. They cool right down between use.

But I'd rather run a 5 litre tank and a cooler than 25 litre, due to the weight and the space it takes up. I do carry 10 litre of engine oil though, which gets more abuse as an oil

Re reckoned with Robot Wars that a CV boot would do as a tank. Never proved it, but theory says you only need enough tank to allow for expansion?

I did wonder about mud cooling? The engine and the winch get most work in the thick stuff, with the least available cooling, so it is tempting to run a hydraulic return line really low down on the chassis in thick walled pipe? It would be a bit of work for me at the moment because my return hose from valve to tank is less than a foot long. I'm guessing that less pump loss has to decrease the loss of power to heat, so it should be cooler with a new pump.

[Team Idris]

A bit more thinking and research; I can see why it pulls well now. It kind of falls into place now I see 75 litre/min at 206bar is 28kW. To do the same with a 24volt booster kit on a 4x4 you need over a thousand amps capability. I'm close to the rated load on the dog clutch as well, it being 40hp max.

Anyhoo, suffice it to say that if you ran it for an hour continuously, you could take your pick on which bit disintegrated first

[B reg 90]

Or I caught the breather with the pressure washer? I need a proper level glass so I can tell when the oil is going wrong.

Oil is ordinary hydraulic oil, which is 10 I think.

Even if we are on a punch for 15 minutes we can't be winching for more than 5? And if the oil is acting as a thermal battery, you can count the mass of the motors and the body they bolt too. They cool right down between use.

But I'd rather run a 5 litre tank and a cooler than 25 litre, due to the weight and the space it takes up. I do carry 10 litre of engine oil though, which gets more abuse as an oil

Re reckoned with Robot Wars that a CV boot would do as a tank. Never proved it, but theory says you only need enough tank to allow for expansion?

I did wonder about mud cooling? The engine and the winch get most work in the thick stuff, with the least available cooling, so it is tempting to run a hydraulic return line really low down on the chassis in thick walled pipe? It would be a bit of work for me at the moment because my return hose from valve to tank is less than a foot long. I'm guessing that less pump loss has to decrease the loss of power to heat, so it should be cooler with a new pump.

Google 'smart resovior' or www.variablevolumeresovior.com

It allows you to get rid of the oil tank completely as you are surmising with your CV boot idea. If you search for the 'hydrodymanic' buggy on pirate4x4 - he is running one of these with no hydrualic tank on a full hydro drive 4x4 (hydraulic motor at each wheel).

Adrian

[aniesigh]

On my build ive got two 26cc pumps back to back with a prv between them (set fairly low) so when the winch is not under much tension I get huge flow (and therefore line speed) as the pressure goes up the second pump gives up so as to not overdo it. Truck is still being built so I haven't used it myself yet but I believe saley uses this setup and I bought it of a working truck, can't wait to see it in action!

While on the subject of hydro winching, at the welsh xtrem I saw a chap trying to winch up a steep bank (never properly seen a saley in action even though I've got one! So I was interested to see)

He got half way up the bank and his rear wheel was caught on a bit of a branch and his winch stopped (guessing prv cut in)

I was abit dissapointed to see that as guys had been going up with gp's / red winches.

Is it likely that he just had his prv set fairly low? Or perhaps poorly matched pump and motor maybe?

[Daan]

Google 'smart resovior' or www.variablevolumeresovior.com

It allows you to get rid of the oil tank completely as you are surmising with your CV boot idea. If you search for the 'hydrodymanic' buggy on pirate4x4 - he is running one of these with no hydrualic tank on a full hydro drive 4x4 (hydraulic motor at each wheel).

Adrian

But your not really saving any weight according to this:

'The VVR has the ability to replace conventional reservoirs, which are considerably larger and weights hundreds of pounds. A 7- liter VVR measures 12 x 24 inch and weighs 36 pounds including the oil, the 14-liter version measures 12 x 46 inch and weighs 66 pounds while the 27-liter version measures 22 x 28 inch and weighs 120 pounds.'

Could you turn it into a closed system, using an accumulator? Certainly solves the 'water ingress from pressure washer' problem.

I am surprised your not running a cooler, that would be a min requirement I would have thought.

PTO still rules in my opinion, but thats just an opinion....

Daan

[Team Idris]

'Hydraulic' is 'PTO' with a self-resetting shear pin in my book? And a flexi drive shaft

That's quite a comprehensive 'bag'. Before I went there I thought "bag in a tank" and it isn't anything like that!

I would think an accumulator would put pressure on the pump shaft seals? And keep any air bubbles trapped in suspension (opposite of a vacuum). I suppose easiest might be to cut out the middle man and use the bag off an accumulator in a box?

Two 26cc/rev

If one of these over-speeds the winch motor then two together isn't good? However, could be excellent if you have two hydraulic winches? I'd consider splitting the system up, because my valve splits the pair into series so the oil has to go through both. This means the power drops off, (pressure has to be shared) and the relief lifts real easy when you are monkey-swinging. Two independent pumps would make both work full-pull at the same time

[dirtyninety]

On my build ive got two 26cc pumps back to back with a prv between them (set fairly low) so when the winch is not under much tension I get huge flow (and therefore line speed) as the pressure goes up the second pump gives up so as to not overdo it. Truck is still being built so I haven't used it myself yet but I believe saley uses this setup and I bought it of a working truck, can't wait to see it in action!

While on the subject of hydro winching, at the welsh xtrem I saw a chap trying to winch up a steep bank (never properly seen a saley in action even though I've got one! So I was interested to see)

He got half way up the bank and his rear wheel was caught on a bit of a branch and his winch stopped (guessing prv cut in)

I was abit dissapointed to see that as guys had been going up with gp's / red winches.

Is it likely that he just had his prv set fairly low? Or perhaps poorly matched pump and motor maybe?

A lot of the hydro boys have their PRV's set below the point of breaking a winch line. Snapping a winch line loses huge amounts of time over just re-positioning or moving a branch.

(snapping winch lines isn't much fun either!)

[aniesigh]

I guessed it was just set low to prevent snapping lines but it just made me abit apprehensive!

As for the flow etc, quite possibly not good but as it was recommended by saley I guessed it should be safe.

Aren't the type R's designed to run with a smaller flow pump? (Zf74's?) so I guess the motor in your case being run from a big pump would overspin it but if the motor is a compatible size it may not be a problem?

I don't know enough about hydraulics to know what will and won't work hence I took saleys advice,

But I am right in thinking then.. That a (let's say) 26cc pump will displace 26cc of fluid per rev.

If I'm using an 80cc pump, does that mean it requires 80cc of oil to flow through it to complete one revolution?

And then if the max rpm of the motor is say 3k rpm then the pump would need to be doing 9230rpm to max it out? (80/26x3000)

And therefore when both pumps are going it would drop to ~4.6k rpm?

Orrrr have I completely mis-understood the way pumps and motors cc's work?

Novice hydraulic Q's!

[Jamie_grieve]

One of my observations of hydraulic winches at the Phoenix challenge last year was they were all getting really hot. Saley himself with a yellow independent buggy had to abandon a recovery for a long time due to really hot oil. In his defence, he'd recovered everybody from the section and I doubt the Gigglepins would have kept up such long heavy pulls for as long as he did. Also everyone he had recovered had an electric winch of some kind.

I reckoned the hot hydraulics were because people were feathering them to control them all the time instead of opening the spool up fully. If you have a hydraulic pump capable of using say 20Kw and you partially open a spool the oil is no longer bypassing the spool freely but is constricted and is either working the winch and getting hot or being returned to the tank in a hot condition from the spool. You can have 5Kw of work getting done and 15Kw of heat happening. The same situation with the spool fully open would result in the winch moving faster and cooler.

Swashplate or variable displacement type pumps and motors would avoid this but then you're into closed circuit hydraulics and cooling gets fun as well.

I still think a hydraulic winch should be more effective than electric in terms of speed and reliability but in real life in challenge events (not industrial or heavy applications) the electric winch is still king. I wonder for how long?

[Team Idris]

I think above is spot on with heat. You can really hear our valves when part open, but they are quiet on full. If I've taken one thing away from my job at GDM, it is that 'duty cycle' (as they call) is everything. If you run a 'thing' part time you can really cut back on the cooling. And that any metal surface, such as my 2 gallon engine oil tank, will cool if you have a fan by it.

You have to be a bit careful on measuring heat though. Up to 75 deg-c is fine, but 50 is owy to the touch I've ordered a level glass with a thermometer with my new pump for a better idea of what is going on.

Math says my 27cc/rev pump and 100cc/rev motor mean the 250rpm motor rated speed is reached at 1000rpm ish, just over tickover. And I reach the safe-short-period-max at 1400. And 3000 crank speed is just bad? What I don't know is if the motor can do more speed off load than its full-pressure speed rating?

[Boothy]

Saley on his yellow bulldog uses 80cc motors which are great for his motor, but it was not designed as a recovery truck so it will get hot with prolonged use above what it was installed to do (pulling big STUCK heavy Buggies that have no drive or batteries left), and it doesn't have cooler fitted.

Bigger motors (which he doesn't need) would overcome this.

I'm just in the process of fitting a pair of Saleys with a crank (via front pulley crank propshaft) driven Group 3 50cc pump and a Group 3 air actuated dog clutch, and 100cc motors, this will plumbed on the pressure side in 1/2" pipe with 3/4" fittings, tank is the weekends job and is of a unknown size yet, I don't at this stage intend to fit a cooler.

The tank will be on a frame under the passenger set where my 3 big Optima's were and will sit just over the chassis rail, so we wait and see how big a volume.

The engine is a big Rover V8 all whizzy gas flowed heads, cam etc, etc, just built, I have also supercharged it (which is awesome), and via the Megasquirt it will run launch control when the pump is enabled, this will then let allow me rev limit the engine to 2000RPM.

It has been on the rollers and produced some VERY healthy figures especially low down torque, the radiator is in the rear so under bonnet temperatures are not to bad (in fact its quite cool) so this is the next couple if weeks work, will keep you posted.

Hey ho back to the thread....

[zim]

Mr Booth is a little strange in the head ?

[Boothy]

Running RICH Mr C, pot calling kettle, etc etc etc......

[Team Idris]

2000rpm limiter sounds a very good idea.

We put the pump clutch in at 10:00am and if we are very lucky we drop it out at 4:00pm (but this is fairly rare as we normally break down by dinner). While I'm nobbin' around in this area I need to follow Boothy with a cab lever. It's long overdue.........

Proper thread diversion; Parts arrived today for Helicopter. Time to charge it up and go break it again

[zim]

Rev limiters are for big girls ?

[Bull Bar Cowboy]

10 litre steel tank and no cooler.

I would have said that 10L is very much on the small side. I used to run a 35L tank with ISO32 oil and no cooler , however, after pronlonged heavy winching the tank would be too warm to touch for any length of time. The tank was mounted in the load bed to allow free air flow.

When I built the system I took the advice of a local independant hydraulic company who were recommended to me. The advice from their resident engineer was excellent with increased bore piping and a much larger filter fitted in the tank to ensure better filtration (pump killer) and flow. The oil was changed every 12 months.

[Anderzander]

Ian

May I ask please - do you have any of the pictures left from your thread here :

http://forums.lr4x4.com/index.php?showtopic=25692

It'd be super helpful if you do ......

Stephe

I would have said that 10L is very much on the small side. I used to run a 35L tank with ISO32 oil and no cooler , however, after pronlonged heavy winching the tank would be too warm to touch for any length of time. The tank was mounted in the load bed to allow free air flow.

When I built the system I took the advice of a local independant hydraulic company who were recommended to me. The advice from their resident engineer was excellent with increased bore piping and a much larger filter fitted in the tank to ensure better filtration (pump killer) and flow. The oil was changed every 12 months.