Winch Choices

[b101uk]

“100% rated pull doesn’t mean stall speed”

Sorry but

100% pull HAS TO MEAN STALL SPEED, no ifs ands buts! Doh or it would pull >100% RATED load, witch is an no-no unless you are load testing for the purpose of S.W.L or structural testing for the purpose of M.B.L

BS 7906 requires a factor of safety of 8:1 for lifting (S.W.L, M.B.L / 8 = S.W.L)

BS EN 1492-2 requires at least 7:1, Supply of Machinery (Safety) Regulations (M.B.L, RATED load * 7 = M.B.L)

Or you have delibretly set you PRV to much lower, in witch case however you cut it, maximum pull will still be a stall speed for the preshur the motor is runing at via a reduction in the PRV seting!

If the winch was rated at 80% like Boughton do then that’s fine, you can have a rated pull and still have line speed, BUT any winch or lifting device unless its say quite specifically says 80% rating etc then anything that says RATED “PULL” or “LOAD” is always assumed to be 100% load ware stall takes place, ware conversely unless it specifically says “line speed @ rated load” or words to that effect, then its always assumed to be maximum “free load line speed”.

Look at it this way if you are pulling 12000lb @ 30ft/min or 0.5ft/sec then you still have HP left to convert fully to torque, hp = torque vs. speed, ergo if something is pulling 12000lb @ 30ft/min its not a 12000lb winch!

550lb @ 1ft/sec is the same as 1100lb @ 0.5ft/sec, 12000lb / 1100lb = 10.909090909090909090909090909091HP or for arguments sake 10.9HP this is the amount of HP required to move the above load @ the above speed, witch means the winch system still has 10.9HP or 359700lb/min 5995lb/sec of potential pull at the rope end to dissipate as net load still remaining before stall, witch would mean the winch would have a rating of at lest 18000lb (12000lb + 5995lb HP potential)

12000lb * 60sec = 720000lb/min, if 33000lb @ 60ft/min = 1hp (550lb @ 1ft/sec) then 66000lb @ 30ft/min also = 1hp, so 720000lb/min / 66000lb = 10.909090909090909090909090909091HP

If the hydraulic motor that powers the MM winch has a maximum torque of 394nm = 290.5lbft and the winch a gear ratio of 6:1, then can some one tell me how the hell you expect 12000lb out of it a 2.5” drum centre?

290.5lbft * 6 = 1743lb @ 1ft from drum centre, or 20916lb @ 1” drum centre, 2” drum centre = 10458lb, 3” drum centre = 6972lb, 4” drum centre = 5229lb, 5” drum centre = 4183.2lb, 6” drum centre = 3486lb, ergo at 2.5” drum centre with a motor with 394nm (290.5lbft) of torque and a winch gear ratio of 6:1 then the maximum pull will be <8366.4lb and not >12000lb or even >10000lb for that mater! And that doesn’t include mechanical losses threw friction etc witch normally range from 5% to 10% in gear system due to oil viscosity & thrust losses in the gear train (gears pushing them self’s apart)

“Pressure drop figures aren’t necessary - look up the performance graphs of the pump and motor, hydraulics manufacturers tend to be helpful like that”

Yes they are very helpful like that, BUT performance graphs of the pump and motors are given at know Pressure both in feed and return pipes &/or spindle loads if you look carefully, as no 2 different systems will have the same Pressure drop in the motor return lines in different application due to the amount of internal restriction from pipe bends and hose length, filtration, valve blocks, etc, etc, so the potential torque and HP output will vary moderately with this, a motor with full pressure drop on the return and a drain pipe will produce significantly more torque & hp at much border speed range than a 2 pipe motor that has a partial pressure drop on the return.

b101uk

[dollythelw]

stall load is stall load - by its definition its when the winch ceases to pull and stalls............ at that load it isnt pulling, maximum pull would for the purposes of this discussion be the maximum load the winch is capable of pulling surely? or would it be more convenient to claim a 200tonne maximum pull? the winch would certainly have stalled at that point? ahh yes seems thats par for the course with leccy winches so I see your point.

Pressure drop over motor ports is a fair point although performance figures mitigate this to a fair degree with flow rate hence manufacturers providing torque figures at given flow rates and pressures - if winch systems were so poorly designed that they provided insufficient pressure drop over the ports due to backpressure in the lines the winch effort would be minimal, the simple method of testing the physics is to no-load the system, apply maximum flow rate and watch the pressure guage - flow rate defficiencies would be fairly easy to spot. feel free to come and have a look at mine, I would welcome the input (and no I dont sell them)

moving onto units of power, rather than bushells per ox month lets try kW,

Hydraulic power is

(Flow rate (ltr per min) x Pressure (bar)) / 600

60ltr per min x 205bar = 12300/600 = 20.5kW (27.49hp)

If you want to go back to imperial measurements then using a 240ft/lb motor the first wrap of the winch at would equate to (240x6) x 10.5"( winch centre 3" O/D) = 15120lbs, not a lot I guess...

the long and short of it would be a load cell, the carp stops there and I think it would be interesting to see real world performance of ALL the winches out there, I dont think there is a perfect setup merely whatever works for you but having watched electric winches spit the dummy time after time Im staying with my crappy slow, feable hydro it goes places, it pulls all day and all night and does it without failure for 8 days straight.

Nice to have a good tech debate though - welcome to the forum B)

[Hybrid_From_Hell]

stall load is stall load - by its definition its when the winch ceases to pull and stalls............ at that load it isnt pulling, maximum pull would for the purposes of this discussion be the maximum load the winch is capable of pulling surely? or would it be more convenient to claim a 200tonne maximum pull? the winch would certainly have stalled at that point? ahh yes seems thats par for the course with leccy winches so I see your point.

Pressure drop over motor ports is a fair point although performance figures mitigate this to a fair degree with flow rate hence manufacturers providing torque figures at given flow rates and pressures - if winch systems were so poorly designed that they provided insufficient pressure drop over the ports due to backpressure in the lines the winch effort would be minimal, the simple method of testing the physics is to no-load the system, apply maximum flow rate and watch the pressure guage - flow rate defficiencies would be fairly easy to spot. feel free to come and have a look at mine, I would welcome the input (and no I dont sell them)

moving onto units of power, rather than bushells per ox month lets try kW,

Hydraulic power is

(Flow rate (ltr per min) x Pressure (bar)) / 600

60ltr per min x 205bar = 12300/600 = 20.5kW (27.49hp)

If you want to go back to imperial measurements then using a 240ft/lb motor the first wrap of the winch at would equate to (240x6) x 10.5"( winch centre 3" O/D) = 15120lbs, not a lot I guess...

the long and short of it would be a load cell, the carp stops there and I think it would be interesting to see real world performance of ALL the winches out there, I dont think there is a perfect setup merely whatever works for you but having watched electric winches spit the dummy time after time Im staying with my crappy slow, feable hydro it goes places, it pulls all day and all night and does it without failure for 8 days straight.

Nice to have a good tech debate though - welcome to the forum B)

Hmmmmm Yeppp

Load cell

Mr Moglite has one and is arrnaging a Winch tugging challenge with all sorts of exotic electric winches, and I have also offerred to completely muller sorry have a go with my silly little punny PTO hydraulic excuse for a winch if I can put up with the sniggers and giggles from the 'Amp Champs'

Mmmmmmmmmmmm thats should be interesting in a "real life" cell destruction test

Nige

[dollythelw]

name the place Nige, Im up for it, I like definitives - perhaps an endurance test chucked in would be cool? 600metres? 1km?

[Hybrid_From_Hell]

name the place Nige, Im up for it, I like definitives - perhaps an endurance test chucked in would be cool? 600metres? 1km?

Elecly vs Hydro power...............

Mmmmmmmm "I love the smell of lead acid boilin' in the morning"

Moglite, common pull yer finger out chap and get this back on track, how bout BKF Alton ?

Nige

[b101uk]

Hi

“stall load is stall load - by its definition its when the winch ceases to pull and stalls............ at that load it isnt pulling, maximum pull would for the purposes of this discussion be the maximum load the winch is capable of pulling surely? or would it be more convenient to claim a 200tonne maximum pull? the winch would certainly have stalled at that point? ahh yes seems thats par for the course with leccy winches so I see your point.”

I see your point, but if something will lift or pull say 12000lb then I add an extra 1lb and it stalls, is it a 12000lb winch or is it a 12001lb which? There is still 12000lb or 12001lb load hanging off the end of it regardless of if its staled or not, load dose not evaporate when something stops, just the requirement for HP evaporates

You then get onto the legal side of things, it is a requirement for a manufacture to clearly state the maximum load something will exert, witch is ALWAYS at stall load, as this is the point the mechanism comes to a stop due to maximum load vs. available power etc, otherwise it becomes far to hard for average people to calculate the maximum load working from percentile figures other than 100% or having to account for speed in equations, much like we are doing now

”Pressure drop over motor ports is a fair point although performance figures mitigate this to a fair degree with flow rate hence manufacturers providing torque figures at given flow rates and pressures - if winch systems were so poorly designed that they provided insufficient pressure drop over the ports due to backpressure in the lines the winch effort would be minimal, the simple method of testing the physics is to no-load the system, apply maximum flow rate and watch the pressure guage - flow rate defficiencies would be fairly easy to spot. feel free to come and have a look at mine, I would welcome the input (and no I dont sell them)”

I agree with that.

”moving onto units of power, rather than bushells per ox month lets try kW,

Hydraulic power is

(Flow rate (ltr per min) x Pressure (bar)) / 600

60ltr per min x 205bar = 12300/600 = 20.5kW (27.49hp)

If you want to go back to imperial measurements then using a 240ft/lb motor the first wrap of the winch at would equate to (240x6) x 10.5"( winch centre 3" O/D) = 15120lbs, not a lot I guess...”

I think part of the reason that you see different things to me, is we work from different ends of the same system using different units and formulas, I tend to work from the hook backwards witch conveniently means I don’t have to calculate the “efficiency” of each part of the system or it is easily assessed from differences in input/output, I have a feeling you are working from the pump end forwards witch means you have to calculate the efficiency as part of your equation, it intrigues me that you are using a circumference witch would be used a speed/distance oriented calculation, rather than a radius witch is used in basic leverage (torque) witch is what a winch is.

using a 240lb @ 1ft radius to the motor shaft and a 6:1 gear ratio I expect <1440lb @ 1ft radius to the winch drum, 1440lb @ 1ft = 17280lb @ 1in, if the centreline of the cable on the 1st layer is 3in radius from the drum centre, then 17280lbin / 3 = 5760lb @ 3in radius, to check this is correct 12” / 3” = 4, so 5760lb @ 3in radius / 4 = 1440lb @ 1ft / 6 = 240lb @ 1ft radius to the motor shaft, so we have calculated in a full circle back to the starting point so know its correct!

If I equate this to my PTO FW525, witch has a 48:1 gear ratio and a maximum torque input at the PTO shaft of 85lb/ft and a 1st layer centreline radius of 3.12” then, 85lbft * 48 = <4080lbft * 12 = <48960lbin / 3.12” = <15692.3lb line pull at stall

the long and short of it would be a load cell, the carp stops there and I think it would be interesting to see real world performance of ALL the winches out there, I dont think there is a perfect setup merely whatever works for you but having watched electric winches spit the dummy time after time Im staying with my crappy slow, feable hydro it goes places, it pulls all day and all night and does it without failure for 8 days straight.

Very true, its very easy to make a primitive but accurate load indicator that would work on all winches, it just takes a hydraulic ram of a known surface area and a pressure gauge screwing into it after you have manually charged it with oil, so at zero pull the gauge reads 0psig and at x pull the gauge would read ##psig vs. ram surface area = line pull

Like you I wouldn’t have an electric winch, my FW525 is now 21 years old and has worked very hard in the past, just need to find a >20000lb hydraulic winch to put on my Unimog.

mmm a winch-off sounds good, but only 600m or 1km, why not go the hole hog for 1mile ~1.61km it will give me a chance to make a brew for you all as you cross the line after me

Should that not be Elecly vs PTO Hydro power vs. strait PTO power

[Hybrid_From_Hell]

What winch set up have you go yerself then ?

Nige

[pugwash]

it will give me a chance to make a brew for you all as you cross the line after me

i wouldn't be too sure of that- Nigels isn't exactly slow, whilst Jez's setup makes Nigels look like a worm drive on 6V!

Should that not be Elecly vs PTO Hydro power vs. strait PTO power

yeah that's a very good point.

although it should be:

standard elleccy v souped elleccy v Standard hydraulic v pto hydraulic v Type r v mechanical PTO

i'm betting on the type r for speed and possibly power- although not with H12s fitted. Mechanicl PTO for pure power i reckon.

[MogLite]

Moglite, common pull yer finger out chap and get this back on track, how bout BKF Alton ?

Nige

Fair comment - but we need a PTO winch in there for comparison purposes - mine !!

Best I (we) get it working then - eh Nige.

I'm pretty max'd this month getting ready for Seven Sisters, but BKF Alton in October should be do-able.

Bathtub isn't too far away - so he could be "Mr Twin Motor 8274" That would be a pretty fair cross-section.

Andy

[Hybrid_From_Hell]

Hows the bits I machined and welded up gone together so far then ?

Nige

[dollythelw]

Game on

I can sort a decent sized ram and a pressure gauge - dont forget a milemarker is a lowline winch and the rad is smaller than you've allowed for, I think we're hitting the same digits just from different power sources - its all good B)

mile or km - Im easy, bring the kettle, how would you like your tea?

[b101uk]

“What winch set up have you go yerself then ?”

I have a Fairey 525 P.T.O on the front of my LR90, it’s a bog standard vehicle, but for years it was used for work pulling big trees down with the stumps attached! Obviously digging was involved as we are talking 1m+ diameter! But when you put ~7000kg of pull 50ft to 70ft up a tree and you attach enough immovable mass to the back of the land rover its surprising what will happen, ~7000kg pull at 50ft is = to ~350000kg at 1ft

I was going to convert it to hydraulic as I have a spear PTO hydraulic pump for the back of the lt230 to replace PTO drop box and a suitable motor to drive the 525 but I have other more important things on my land rover & Unimog to do, but I really would like a rear mounted Fairey 525 or mayflower as well, simply as people strangely don’t like them or perhaps it’s the names that scares them off, oh the irony

b101uk

[MogLite]

Hows the bits I machined and welded up gone together so far then ?

Nige

PTO is now 100% thanks

Need to machine a bearing carrier for the H14, and maybe a thrust washer. But I haven't had time to look at the exact requirement yet - too busy playing with big tyres.

[AVIT]

I ran milemarkers and up rated the speed 4 years ago prior to the Type R motors. what I dont like is the fact they don't have a brake, when lowering the winch it would run on. How do you resolve that problem, fit an inline none return valve?. But have to say they never, ever failed me.

Have aquired a new truck (ex-Tony baskill) with an 8274 hybrid electric/hydraulic set up which I want to lose/sell and replace with the milemarkers, just need to find some one to fit the pump etc for me as I dont have the patience or the tools. any takers

[BogMonster]

I ran milemarkers and up rated the speed 4 years ago prior to the Type R motors. what I dont like is the fact they don't have a brake, when lowering the winch it would run on. How do you resolve that problem, fit an inline none return valve?. But have to say they never, ever failed me.

How did it run on? I have a std MM and when you release the button it stops dead. Granted it doesn't have one of those fancy valves to protect it in case of hose failure but once the valves are closed the fluid can't go anywhere?

Mine has a tiny amount of hydraulic creep in the motor when you stop it and there is a high load on the line, but not enough that you can even see it moving back in low range, you just hear a slight noise.

[dollythelw]

Over centre valve stops the creep you had an issue with, what engine do you need the pump fitted to AVIT?

[AVIT]

Over centre valve stops the creep you had an issue with, what engine do you need the pump fitted to AVIT?

I ran a 47LPM pump on twin v belts but they slipped under a big load, so fitted PTO as a back up, increased pipes to 1/2" which increased speed. This was all on a 2.8 inline six cylinder. But with my new truck (5.6ltr V8) thinking of chain or toothed belt with a pump to go where the aircon compressor is which iscurrently used to power a small hydraulic motor thats on this 8274 elctric/hydraulic hybrid, so the size of the pump is going to be limited If I want a 50LPM to get a type R motor to spin. I currently have the original motors on both MM so would need to upgrade motors first. What LPM pump should I be looking At because the 47LPM I have on my other truck is bloody huge.

[AVIT]

How did it run on? I have a std MM and when you release the button it stops dead. Granted it doesn't have one of those fancy valves to protect it in case of hose failure but once the valves are closed the fluid can't go anywhere?

When I mean run on I meant that paying out it would payout faster than the motor would normally allow on a steep hill decent, and it would make a terrible noise. I should've made that a bit clearer.

[Hybrid_From_Hell]

AlthoughI am a Hyd Winch Fan, it is fair to say that the chances of experiencing "Overun" on a MM of any notice are erm "Slim"

Noticing the difference between winching in a staionary can take practise

Nige

PS Glad to get in with this post pre the electric mob,

prob busy cooling their motors and charging the batteries back uo before coming here to post

[FridgeFreezer]

You forgot to mention boiling their kettles on the windings of the motors

[Hybrid_From_Hell]

[Tonk]

OI you two, this isn't the bunfight thread

lets just hope its raining when u get stuck cos then your engines will conk out and you wont be able to winch yourself out anyway

atleast we leccy winch users can keep our hands warm

[FridgeFreezer]

With a rear winch you can keep your hands warm whilst pushing

This joke was adapted from an original Skoda/Heated Screen joke first told circa 1794 by Bob Monkhouse.

[dollythelw]

the physical dimensions of a 47ltr pump and a 60ltr are very similar. The factory G belt setup only seems to work when you're not really stuck, a friend has one and his belts slip

This is the chain drive setup thats currently on my runaround - theres a lot of positives from chains in terms of cheap servicing, easy setup, durability etc. The dog clutch can be air/cable or rod actuated and ensures you only drive the pump when you need to.

If you want to go belt then theres a couple of options, multi-polyvee (more and more belts, more and more radial load - ouch), or toothed.

To drive a Type R setup with a toothed belt you need to be running a minimum of a 30mm wide HTDP-3 belt on an 8mm pitch, Gates or Fenner are the best, Pulley diameter also has a minimum figure (to ensure that theres sufficient tooth count in contact with the belt) 100mm upwards is sufficient. Maximum axial runout with a belt is 0.25 degrees - any more and the belt will run off the sprocket lips.

if you feel like checking the maths then look at the Drive designer

all piping will have to be 1/2 bore apart from the delivery pipe from the tank. Tank design is also important.

No household plumbing or brasso is required though and unfortunately it will continue to work all day, every day

if you want to get round the old peanut of "oh but your winch doesnt work when your engines dead" then add a tailift pump in circuit with a one way valve.

[pugwash]

add a tailift pump in circuit with a one way valve.

i'm just doing the design for my winch circuit at the moment- finding it really ahrd to get specs for electro-hydraulic pumps- would a tail lift pump be better than a saxo PAS electro hydraulic PAS pump?

Also just thinknig about line design.

Have tank with main feed to PTO pump which then feeds spool block. Need to add the electric pump between tank and spool to cut out PTO. That means i need a 3-way ball valve or similar just downstream of the tank to divert fluid to the relavent pump.

Would you then need to put a three-way one-way valve in just before the spool block? this would prevent the working pump from overpressursing the out of service pump (which would usually be electric. Would it be the case that as the up stream side of the PAS pump was shut off then you are effectively working a closed system so having a one-way valve woudln't be neccessary?

to re-phrase in case i'm not being clear- could the pressure produced by one pump affect the other pump, if the other pump coulnd't physically have any flow past it?