Hello + winch query

[allforham]

Hi everyone

New here, just started logging here in New Zealand last summer, small scale operation aimed at being able to log very small blocks at low cost. Running a 14t komatsu excavator, cat 931b with a small trailer similar to an arch without the arch(we just load with the other machine it has a roller so it self unloads) and a small delimber which the 14t can use. All together slower than big gear but cheaper to buy/run/fix and we manage 1-2 trucks a day with 2 of us which I think is ok?

Anyway my question relates to setting up a winch on the hitch of the komatsu. Have seen a few other threads on here and it appears there are some very knowledgeable people about. My own knowledge is very  basic currently.

I have bought an allied h6g hydraulic winch, designed for a dozer but I am hoping to make it work. Have studied the workshop manual and think I have a decent understanding of how it works. Lower pressure pilot controls with some 24v solenoids to switch certain functions, high speed, brake off, freespool etc. Then higher pressure (3500psi) to run the winch.

My problem is the komatsu runs more like 5000psi. We only need power in and freespool. Maybe high speed if possible. I was thinking of running the winch in one direction off the aux hydraulics in breaker mode, giving a case drain. Then feeding the pilot controls with the quick hitch hydraulics which I believe are always under pressure? This may be system pressure though so maybe way too high?

The winch is designed to work with a load sense pump on the dozer, the komatsu does use a load sense pump of some sort but I would have no idea how to tap into it, or even how it works if I'm honest.

As you can probably tell I'm largely flying blind so any advice would be greatly appreciated!

Adam

 

[kiko]

The only way to ever make this work properly IMHO, you would need a dedicated pump with above specs.  You can see in the valve for the winch motor is a check valve.  This is the load sense check valve , for it to work properly off the existing excavator hydraulics this check would have to be somehow incorporated  into  with the load check system of the main control valve other wise the pump would never leave the static displacement standby unless you work another function at the same time to trick the main pump swash plate . And the motor control valve shows to be part of the winch assembly with the pump and winch controls being provided from the tractor.  If this excavator has the Cummins clone Komatsu engine there is port for an accessory drive to be added to run the dedicated pump.  At 6.1 cubic inches per revolution and 2200 rpms , about 60 GPM . Do you know the flow rate of the excavator?  If your machine flow rate is close to that then you may be able to bypass the control valve in the winch and plumb in the hammer valve directly to the winch hydraulic motor.  Still have to deal with the pressure issue.  

[allforham]

Thanks Kiko

The flow rate is actually remarkably close. 240/lm which I get as 63 gal/min. I had thought about bypassing all the directional controls and running the winch direct I would still have to release the brake though. Maybe run a tee to accomplish this with a pressure reducing valve to the brake? Although the diagram says it will handle 3000psi. Would it be possible to adjust the auxiliary pressure relief closer to 3500? Or would this just overheat the oil?

At this point wishing I'd had this discussion prior to buying it but seems I'll never learn! Very much appreciate the help

[mike_belben]

I think you should sell it and get a military 6x6 5ton truck winch.  Theyre as simple as can be, easy to mount, have freewheel, and are plentiful. 

[allforham]

Thanks Mike 

Unfortunately here in nz I struggled to find anything much hydraulic that was semi affordable and shipping is taking months at the moment! Need one for a job coming up. Is there anything special about this motor which means it'll explode if I simplify things?(with reduced pressure)

[mike_belben]

I didnt think about that island issue abd i dont know the answer on the winch.  At a glance it is way more complicated than necessary for a basic dozer winch.  You either want a reel that is freewheeling over a PTO shaft with a drum that is coupled to the PTO energy by a friction coupling, or a worm gear with hydraulic drive abd a freewheel so you dont wait all day to reel out. The military winches in america are the later.  

Either of those is real simple.  The schematic on that allied screams too complicated for a backyarder to me.  Initial release, full release, solenoids.. Thats a lot of tech to pull a cable.  A tractor with a chopped and welded rear and a rim will pull a cable, notches in the rim work fine for a hold brake. You dont need to be spending all your money to get this thing working and then the rest on figuring out why it stopped working in the future.


Find someone who has the machine that winch was designed to go on and send it down the road. Stay simple.  Logging has plenty of other problems that will need your time and money. Just my 2 cents

[allforham]

Cheers mike 

There's really not the market for it here to sell in a hurry, probably why it was comparatively cheap! Have come up with an idea to make it work, let me know if you see any obvious faults in my plan.

Use the machines aux lines to run the winch direct, with relief valve adjusted for 3500ish psi if I can figure this out. Have my eye on a small 24v hydraulic power pack with 2x electric solenoids locally. I could hopefully set this closer to 700psi and use one to release the brake(wired in with the aux switch on the machine?) And the other to operate freespool) this would have the benefit of not needing to have the machine idling all day while we drag out

Can you see any reason this wouldn't work?

[kiko]

I think you could make it work .  You may have to eliminate the winch control valve completely from the system. DO NOT stack relief valves.  Often the aux port on an excavator has feed reducer valves which can control single function pressure.  I would think you could control the low pressure aspects of the winch control by tying into the existing pilot control pressure of the machine.  I would want to know for sure that the hydraulics of the winch are clean so contamination of the Komatsu would not be an issue.  I am only self taught so take what I say with a grain salt , but i would probably take that job on if it was here because I like a challenge.  Consulting a hydraulic engineer if possible would be wise.

[fluidpowerpro]

To feed your pilot controls you could tap into the charge circuit of the closed loop hydrostat pumps. 
To run the winch off of the load sense pump, you will need a "load sense" check valve to tell the load sense pump when to come on stroke. This small check valve is plumbed in between the winch control valve and the winch motor and then is plumbed into the existing load sense pilot sensing circuit. If you want to limit the pressure to the winch to 3500 PSI, put a small orifice before the check valve (.030"). Between the orifice and the check valve, plumb in a small relief valve that is set for 3500 PSI. This will limit the pressure to the winch to 3500 PSI, anything higher and the load sense pump will de-stroke.

[allforham]

Thanks for the replies. Have had a look inside the winch and it would be very easy to run hoses directly to the winch motor through a side panel. I think trying to make the winch directional control valve work with load sensing etc is likely beyond my abilities. Will try this power pack which is only $300 to release the brake and engage freespool and if that doesnt work I will look at tapping into the excavators hydraulics. Will report back with some pics once I am successful or or less so!

[teakwood]

I am only self taught so take what I say with a grain salt ,

oh boy, don't sell you self short kiko, you probably #1 guy on this entire forum when it comes to heavy machine repairs! right followed by Belben, you guys amaze me every time with your posts about hydraulic and mechanical solutions!! i learned a thing or two from your posts, that's for sure, keep up the good work ;)

[mike_belben]

Thanks ramon but im not half the wrench that kiko is. 


Ham.. If you can rig this thing for direct plumbing to the motor ports you can have your own control valve and toss the allied control section.  Thatd get you half way there.

Can the holding brake be rigged to something mechanical so you can pull a lever to a cable that backs it off?  


I assume the brake is spring on and hydraulic release.  Is there a ram or just a hydraulic cavity like an automatic transmission "accumulator piston"?

Or can you make room for a single acting hydraulic cylinder to actuate the brake release? If so you could use a large 2 spool forklift valve.  The lift spool could release the brake and the tilt spool run the winch motor.  Very small hydraulic cylinders exist for machine part clamping. Enerpac is a common brand. 1/4" stroke, that sort of thing. They can be mounted in threaded bores or offset mounted to fkat surfaces and so forth.  


A destaco toggle clamp is much much simpler if it can work.  Pics of the brake mechanism would really help the ideas flow. Pics always help

[allforham]

 

 

[allforham]

Hi Mike

Have uploaded details of the  brake from service manual. It's just attached to the motor. Looks like it should just   be a case of feeding it 700psi to release.

Was planning on just using the excavators aux circuit and using the joystick button like any other implement. Should be fairly simple to tap into this wiring to trigger a relay and run the wee power pack to release the brake. Can mount the power pack on the winch itself so it's only wiring I have to run the whole way from the cab. What do you reckon?

[Riwaka]

If the thread author looks on the worksafe website. In the machinery section, there is a modification sub-section (changing anything away from the manufacturer's intended purpose) requires a qualified engineer (hopefully a good one) to validate the modifications comply with Australasian standard 4204? (Years ago I knew the hydraulics guys who worked on a Brand  name arb-service company's bucket trucks. They had a separate folder for each truck to detail any work they did, in case the blame game started after an accident)

[230Dforme]

Can't help with specific conversation,
but I have 8 winches on various equipment up to 50 ton pto
Will be adding more

Can't live without them, good luck