Hello!

Although my Warn electic winch never has let me down, I am getting rather tired of strugling with lots of batteries and alternators... (current setup : 4 110 AH batteries and 2 100 A alternators...)

I have had a number of different ideas about either hydraulic or mechanical winches. Managed to aquire and old - but fully functional - toyota mechanical winch, which my first idea was to run directy from the crank shaft. The only drawback of this setup was that the line speed would be scarily fast - some 12 metres pr minute - and some of the more knowledgeable members of this forums suggested that the winch itself might not be up to the job.

So, determined to the things right the first time, I have slowly been aquiring the diffent parts needed to make a hydraulic winch.

I have just bought the last part, namely the hydraulic motor for the winch.

Hydraulic power for the winch will be delivered using a ZF74 pump with electric solenoid valves and oil cooler.

The winch is an old toyota mechanical winch with a gear ratio of 1:36 and a bare drum radius of 0,04 metre. I should note that I have never been able to confirm that the winch indeed should be "toyota"-made - I just know the seller told me so.

The purpose of the winch is self-recovery, and the odd job of pulling some trees down. I do not participate in competitions. Therefore reliability is far more important than line-speed. Actually I think I would be rather scared if I were to use some of the really fast setups for my purposes....!


Calculating the pulling power of the winch:
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From the technical specifications of the OMM32 (se below schematics) it seems that it should be able to spin at about 430 RPM at a flow of 13 litres pr minute, and deliver a torque of 4.5 daNm at just under 120 bar pressure.

For calculating the Drum Torque of the winch I use the following formula:

Drum Torque (daNm) = Motor Shaft Torque (daNm) / Gear ratio

which gives a Drum Torque of 162 daNm (4,5 daNm * 36)


For calculating the Line Pull I use the following formula:

Line Pull (kg) = Drum Torque (daNm) / Drum Radius (m)

Which gives a Line Pull of 4050 kg (162 daNm / 0,04)


This is calculated as a bare drum line pull, and generally under optimal conditions. Still it is a line pull I am quite happy with - if I need any more pulling power I can just double back the winch line using a snatch block.


Calculation of the line speed:
================================

For calculating the Line Speed I use the following formula:

Line Speed (metre / second) = ( Motor Speed (RPM) * Bare Drum Radius (m) ) / ( 9,5 * Gear Ratio )

Which gives a line speed of 0,050 metres pr second (430 RPM * 0,04 m) / (9,5 * 36)

This should equal a Line Speed of 3,0 metres pr minute, which is also a number I am quite happy with.


Winch Power Consumption:
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Click to view attachment

Using the specification sheet for the OMM32 it seems that the power delivered from the pump to run the winch at above specifications should be about 2.5 HP.

This is also a figure I am quite happy with, as this should be well within the limitations for running the ZF74 pump of a normal vee-belt.


* * *

As stated in the topic title, my normal field of expertise is in the computer networking field... This hydraulic thing is quite new - however all the data and specifications of the different components are available on the web and I hope I have been able to puzzle it all together in the right fashion - should there however be some blunders iin my plan I would really appreciate some guidance....

May I suggest you look at your present set-up and find out where the fault is rather than start all over again?

440 AH of battery (which batteries are you using and how old are they?) and 200 amp of charge should be enough!

When you say struggle, what's the problem?

How many motors have you got on the winch?

The purpose of the winch is self-recovery, and the odd job of pulling some trees down. I do not participate in competitions.

As your winch use is not heavy I'm sure we can save you some money!

Hi!

Thank you for taking time to answer my question!

However, the electrics is NOT the problem... For prolonged use electric winches are simply energy-inefficient, due to the large build-up of heat. Providing charge for prolonged use is actually the sligtest of the problems - as I said in earlier post, I find electronics quite simple...!

However solving the problem of heat build-up is not easily undertaken. I could probably come a long way in that direction by purchasing a newer electric winch (My current one is an old Warn 9000), but I find that further investment in the electrics field will be the wrong choise.





Actually, the "saving money" is a little irrelevant, as all the components for the hydraulic system has already been aquired! (For very little money, actually!)


However, I appreciate your comments, and for most others electics are probably still the easiest solution. I just want this setup to be totally reliable for prolonged use. Hauling a fully laden landrover (sometimes with a heavy trailer behind) 100 metre through muddy forrest sections is the kind of prolonged use I find very difficult with electric winches. There are several uses for reliable winches outside the competition scene.

OK.

Good luck with the hydraulics, others will be along to advise!

Just to supplement the above information - this is a photo of the winch:

Click to view attachment

- And just to clarify, - the ruler in the bottom half of the photo is in centimetres, not inches!


I have been told it is a from an old toyota, however there are no references to that origin on the winch...

That is a toyota mech winch most commonly found on 60 series landcruisers, allthough i think they've been around since the 40 series.


Why not use a landrover drop pto and make up some drive shafts and keep it mechanical?

Thank you for that information!

Regarding the PTO option - that has been considered, but so far been disregarded due to two different issues.

Firstly, the PTO drop box seems somewhat vulnerable... This could maybe be rectified by "clocking" the box...,

Second, in Denmark we drive in the right side of the road and have the steering wheel in the left side of the car. This adds a steering linkage to an already crowded section of the engine compartment. I have looked and measured thoroghly, but I cant find empty space enough to run a PTO driveshaft for the winch - unless I accept it to be positioned quite vulnerable.

But thanks for commenting!

Maybe just me, but i cant actually find a question..., but all your calculations seem right

so rather than asking us if it will work, why dont you go and find out if it works!
youve got all the parts you need, youve got the maths to prove it theoretically works

so go build something cool!!!

Hi!

Of course it will be built!....

But I dont think I can find the time before sometime late summer... For the moment I am doing a full-time day-job, rebuling my workshop, and studying to get a degree at the university...

So spare time is a rather limited ressource, and hence the above questions. If a had made some kind of blunder in the calculations - which probably would be rather obvious for preople which normally works with these things - then precious build time could be used more effective by rectifying the mistakes already at the planning stage....


Dont worry, the thing will be built! Never backed down on a project which had been started!


Besides, the purpose of a forum is sharing of information... If the above calculations are correct, then the same formulas might be of relevance for others ...

If you clock a h14 pto gearbox, the pto shaft will end up running just above the gearbox mount and just below the engine mount from there you could tube the front x member of the chassis and take the shaft through there. This route takes the pto shaft out of the way of any steering components.

i may have missed something but if your after relyability (not that hyd winch's aint) if you get stuck in water mud or loose engine power your winch is useless especially if your some where remote this is why am sorting out a back winch then looking in to a new front be it electric or hyd, also to get the temp down why not use a superwinch husky winch which does not build up heat (other than motor) as doesnt have a clutch.
my current setup is a husky at the front and as like you i only want it for self recovery thought that would be the best way to go, and works fine off a single battery standard alti setup.

just something to think about when deciding on your usage for self recovery

hope this helps

dave

The hydraulic setup depends on engine power, but I cant see why getting stuck in water or mud would render the setup useless. The truck is proven submersible to about two meters!

If somehow the truck should get stranded without engine power, then I have sand ladders, hi-lift and hand operated winch. Using the hi-lift as a winch is also possible (Once had to pull the truck 50 meters though thick mud using the hi-lift as winch. It took the best part of a day - and I was rather tired after the experience!

The electric winch will probably be re-located on the back of the truck to assist in such an situation.



No matter how much creativity I use in my mesurements, I cant find room enough for the linkage, without introducing some kind of violence to the steering box. No doubt it can be done, though. Had a call from another dane reading the forum - he has done it with a koenig winch, although he had to "shave" the steering box somewhat with the angle grinder...

Yes you calculations are fine, although I am having some difficulty in believing the manufacturers specs for the motor.............. it seems to be very little flow for the speed quoted.

However, the ZF74 pumps do not seem to flow the quoted 13L/m .............. it is more like 10 or 11 L/min...............


Also the ZF74 has a flat curve so your winch control will be poor without using a spool valve ..........................i.e. it will be on/off like an electric winch but without the overrun associated with electric winch's...............


Sounds like a good project.........................





Ian

Really appreciate your comments, I have read about the hydro-setups you have made - they seems rather "advanced"!

I have a spool valve waiting somewhere, if the electric control block proves difficult to use. However the reason for using the electric control block is the easy possibility of constructing some kind of wireless remote control.

Thank for the information about the ZF74. When the measured linespeed dont match up with my calculations I will know why.

The spec sheet is downloaded direct from manufacturers website - it should be accurate.