Winch power

[SimonInAustralia]

Another thing to look at is what are the pullratings if the cable is spooled out. that 8 K winch is good for 8 K only on the last wrap. The more you spool out the less mechanical advantage you have.

No, that is incorrect.

The ratings are for when most of the cable is spooled out, the more you spool in and onto the drum, the less it will handle.

From the Warn basic winching guide...

How the Winch Reacts to Load
Warn winches are rated by pulling
capacity.The maximum pulling capacity
occurs on the first layer of wire rope on
the drum. As the layers increase, the
pulling power decreases. It’s the mathematics
of winching.

 

[charlieaarons]

It seems with larger vehicles and hydraulic winches 40-60% of GVW is the rule. My U500 has a 20K hydraulic DP on the front and a 15K hydraulic Superwinch on the back. I've only needed them twice, so far they've been enough. The truck weighs 25-27K lb. completely full of fuel and water and stuff. I do carry a pulley, cable extensions and several anchors.
A 40,000 lb winch on my vehicle would be a little big, although theoretically I do have the front GAWR to carry a 1000 lb winch.

Charlie

 

[4Rescue]

Anyone any experience with T-max winches?
I'm about to get me this one:

YES... Great Winches IMO. I used them in AUstralia and tried my dam'dest to kill several of them but they didn't give up. I've herad of failures here and there, like every other brand, but nothing too serious like the soleniod going out or broken internal gears. In fact some fo the new flash models use solid-state electronics and are completely submersible. The models I ran were older and not nesssicarily the top end models of those years and they still ran like champs.

Can't go wrong with Warn either... Gotta show some love for my Hometown Hero's you know

Cheers

Dave

 

[michaelgroves]

It seems with larger vehicles and hydraulic winches 40-60% of GVW is the rule. My U500 has a 20K hydraulic DP on the front and a 15K hydraulic Superwinch on the back. I've only needed them twice, so far they've been enough. The truck weighs 25-27K lb. completely full of fuel and water and stuff. I do carry a pulley, cable extensions and several anchors.
A 40,000 lb winch on my vehicle would be a little big, although theoretically I do have the front GAWR to carry a 1000 lb winch.

Charlie

Of course a lot of winches fitted to working trucks are for purposes other than self-recovery, and therefore their capacity is unrelated to the vehicle's GVM. I can't imagine why any "rule" would be different for bigger vs smaller vehicles? Other than, of course, that getting stuck is a bigger event in a Unimog than it is in a light pickup, and so the comparative time taken to rig snatch blocks is less of a consideration.

 

[michaelgroves]

I guess another issue with big vehicles is that the chances of finding a secure enough anchor start coming down rapidly, so there's not much point in fitting a 30-ton winch to a 20 ton truck.

 

[charlieaarons]

Muskyman said what I wanted to say about hydraulic winches, but didn't.
Additional fact: If you look at the specs on electric winches, even Warns, and multiply amp draw at rated line pull times 12V to calculate power draw in kw, and divide that into rated line pull X line speed @ rated pull, and convert from ft-lb/sec to kw (33000 ft-lb/min = 1hp = 0.747kw), you will come up with some horrifying efficiency ratings, like in the 10-20% range. Where does the other 80-90% go? HEAT. We're talking several kw of heat at full power. Without a 60L hydraulic fluid volume to dissipate it.
You can do the same calculation for hydraulics, power in = flow volume/min X pressure, and efficiency = ~70%. The only downsides of hydraulics: mainly cost, very secondarily engine must run (how far are you going to be able to winch with no engine power?)

Charlie

 

[4Rescue]

Muskyman said what I wanted to say about hydraulic winches, but didn't.
Additional fact: If you look at the specs on electric winches, even Warns, and multiply amp draw at rated line pull times 12V to calculate power draw in kw, and divide that into rated line pull X line speed @ rated pull, and convert from ft-lb/sec to kw (33000 ft-lb/min = 1hp = 0.747kw), you will come up with some horrifying efficiency ratings, like in the 10-20% range. Where does the other 80-90% go? HEAT. We're talking several kw of heat at full power. Without a 60L hydraulic fluid volume to dissipate it.
You can do the same calculation for hydraulics, power in = flow volume/min X pressure, and efficiency = ~70%. The only downsides of hydraulics: mainly cost, very secondarily engine must run (how far are you going to be able to winch with no engine power?)

Charlie

Very good points and figures.

I think in general electric winches are used for their ease of instalation. AND as you mention you need the engine to run for the pump to work, not so good when things have gone really wrong or the motor goes out. Certainly a hydro set-up would be awesome but I think most folks are daunted buy the thought of setting it up on their rigs. Not to mention the added weight and equipment (although not THAT much weight and equip.). Personaly I think that Hydraulics are great and could be utilized for all sorts of things...

Cheers

Dave

 

[Christian]

Very good points and figures.

I think in general electric winches are used for their ease of instalation. AND as you mention you need the engine to run for the pump to work, not so good when things have gone really wrong or the motor goes out. Certainly a hydro set-up would be awesome but I think most folks are daunted buy the thought of setting it up on their rigs. Not to mention the added weight and equipment (although not THAT much weight and equip.). Personaly I think that Hydraulics are great and could be utilized for all sorts of things...

Cheers

Dave

Well you say not THAT much. But you who are in the know, how much is it for lets say a 12,000lbs winch? And what is needed? I take it that a servo pump won't be enough... or you will have to wait for this:costumed-smiley-007guy to wake up before you get anywhere?

 

[charlieaarons]

A servo pump might be enough, or maybe not, depending on the vehicle. Winches range from Milemarker, which is basically an electric winch with a hydraulic motor, to industrial/military winches made by Warn, Ramsey, DP, Superwinch (I have the latter 2 on my U500), Braden, etc. Cost partially depends on rating. A Milemarker 12000 kit (all the plumbing and electrohydraulic valves) might be approx. US$1200 (in the US). More or less.
If you run off the power steering pump an additional fluid reservoir is highly advisable to dissipate heat.
The "ultimate" hydraulic system is a PTO off the engine or transmission driving a pump. But even my U500's pump runs off a (dedicated) heavy duty serpentine type belt, even though the pump can generate up to 27kw power, and another option is rated up to 45kw, plus it also drives the (hydraulic) cooling fans which could be another ~15kw. So a belt drive is not necessarily a limiting factor. If it's a big wide grooved belt.
Call Milemarker with the mfg. and model of your pump. If that will work it will be reasonable. If you build a system from scratch using a transmission PTO it will not be cheap.

Charlie

 

[SimonInAustralia]

The only downsides of hydraulics: mainly cost, very secondarily engine must run (how far are you going to be able to winch with no engine power?)

With an electric winch, and the power needed to run it, is a battery going to last very long winching without the engine running?

 

[4Rescue]

With an electric winch, and the power needed to run it, is a battery going to last very long winching without the engine running?

Very Valid point, although it certainly will pull longer then the Hydro Winch with NO engine running eh But hey, we drive Toyotas so our motors tend to stay running longer HAHAHAHAHA I kid I kid...

Well you say not THAT much. But you who are in the know, how much is it for lets say a 12,000lbs winch? And what is needed? I take it that a servo pump won't be enough... or you will have to wait for this:costumed-smiley-007guy to wake up before you get anywhere?

As Charlie said, a servo pump COULD be enough but you'd have to look into the flow requirements for said winch, they're not all the same if I recall correctly. Another thing to think about with a Hydro winch just like a tractor, it needs a hand throtle or an adjustable remote throtle to get the pump spinning enough unless you have multiple people so one can stay in the cab and keep the engine RPM's up. I'm reminded of the first time I played with my dad's beloved Kubota and forgot to run the throtle up... yeah it didn't want to lift much with no pump pressure eh

As for overall package size, it could be argued that there's as much complexity and equipment to a dual battery system to really make your truck work well with an electric winch so really they both have their special needs but in the end I belive that the electric winch will be easier to install if for no other reason then it's been done a trillion times. Not alot of small 4x4's are running full Hydro Winches/impliments. That said, the Idea is the same as running Hydro-boosted or Full-Hydro steering and that's certainly got alot of support behind it. All in all I'd say take your Cruiser to a forklift shop and have them look into mounting an implinent pump somehow...Sorry, now I'm just thinking out loud mate. This has now made me WANT a hydraulic set-up on my truck for absolutely NO reason right now HAHAHAHA I guess part of me just wants to be able to carry some Hydraulic Shear's/Spreader's AW YEAH!!!!!!! Oh and a Hydraulic Chainsaw, that'd be cool... Good god how this site can help us spend our money can't it

Cheers

Dave

 

[charlieaarons]

As Charlie said, a servo pump COULD be enough but you'd have to look into the flow requirements for said winch, they're not all the same if I recall correctly. Another thing to think about with a Hydro winch just like a tractor, it needs a hand throtle or an adjustable remote throtle to get the pump spinning enough unless you have multiple people so one can stay in the cab and keep the engine RPM's up. I'm reminded of the first time I played with my dad's beloved Kubota and forgot to run the throtle up... yeah it didn't want to lift much with no pump pressure eh

Actually having owned several vehicles with hydraulic systems and winches I can say they ALL pulled well at idle - just appropriately slow, proportional to rpms. This "no power at idle" issue might be a problem for someone but I've never seen it; I imagine it occurs if the pump is way too much pump for the rest of the system (in other words an engineering error). Like putting in a pump that's rated at 60 gal/min in an application that puts out 15 gal /min at peak rpm and using a winch with a motor that has peak flow capacity of 30 gal min, so this big winch motor is getting a mere 4 gal/min; or less, since it's so far below the pump's peak capacity.
My winches do get only 4 gal/min at idle; but they are rated for peak flow of 15 gal/min and the pump puts out 12.7 gal/min at peak rpm of 2200. So they work fine at 700 rpm.
Of course on a Mog I have the additional wonderful advantage of being able to exactly match wheel speed to line speed with the crawler gears.

Charlie

 

[Christian]

Not alot of small 4x4's are running full Hydro Winches/impliments.

Cheers

Dave

Well... we are not running a small 4X4... but a small 6X6:coffeedrink:

 

[michaelgroves]

I agree entirely about hydraulics, and yes, it makes a huge amount of sense that a big truck would need something other than an electric winch. You can multiply up the torque of any winch by using a snatchblock (or more), but then you need to run the for winch twice as long under load (or more). So even a small electric winch with a moderate current draw would be entirely unsuitable for a bigger truck.

Musky's right about the MM being very different to the electric wnches I have seen. I couldn't find the link, but on one of the boards there are pictures of an H12000 being disassembled - very impressive innards! And as far as the necessary horsepower is concerned, I have never had to have the engine at anything more than idle to run the winch. Of course, the MM is known to be slow, but it's hardly an issue - it just pulls at a constant speed, all day if necessary. I also went for hydraulic despite all the dire warnings that it wouldn't run without the engine running. Other than the "stuck in a raging torrent" scenario (which is definitely to be avoided when solo anyway), it is hard to see why it would ever be essential to winch before getting the engine running.

I'd have thought any hydraulic winch would be lighter than a similar spec. electric winch? An electric motor is massive compared to a hydraulic motor, and the rest is theoretically the same. If my quick and dirty calculations are correct, the 5500kg capacity of the H12000, pulling at 0.03m/sec under full load, works out at a bit over 1.6kW. An electric winch doing similar useful work at the same speed, would be pulling around 450A @ 12V, so drawing more than 5kW!

(This also explains why no revving of engines is necessary unless you have a pump that is too small: at idle, a couple of kilowatts is hardly noticed. In fact, even if you do rev the engine, the winch doesn't pull faster or harder - the bypass valve just opens because it's already pumping as much fluid as it needs.)

 

[hieronymus]

I'm happy with my winch....found some good use for it several times already!