What would you do with this kit? (pump)

[julianf]

http://www.ebay.co.uk/itm/400611524559

Assuming it works?

This is the motor -

http://www.ebay.de/itm/DC-Motor-Elektromotor-Hydraulikmotor-Gleichstrommotor-Bosch-1517220542-48V-3-7kw-/281095121190?clk_rvr_id=554331242254&lgeo=1&vectorid=229487&nma=true&si=%252Fcyh9ZTdd5InuxaPD4tYeG2nzkA%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

or this -

http://en.startershop.nl/electric-motors/im0078/


but its the gear pump that's more interesting.


If the stamp is to be believed, its 1200lpm???


Anyhow, ive got some ideas, but im wondering what other people would use it for?

[knighty]

it's a forklift hydraulic motor

it's almost the same as the the one I just stripped out of my old forklift

it'll only be very low flow, but massive high pressure

maybe it's 12litres/min ?


did you win it ?

[julianf]

From looking at the motor specs, i think it must be rpm, not lpm, although the stamp certainly looks like lpm.

Yes, im the owner.


I was thinking that i could junk the motor (well, relist on ebay) and possibly couple the pump to either another electric motor, or a small engine.  Or keep an eye out for a 240v / 16amp 48v psu.

I want to make a press.  It would be cheaper to take apart a log splitter, but it seemed like i would get more pressure from this unit.

[knighty]

3700watts at 48v is 77amps

but I think it'll pull a lot more than that when you're using it at high pressure

you might be best off with 4 old batteries with 4 little cheap chargers on them ?


(if you do sell the motor give me a shout, my nephew is desperate for me to build an electric go kart with the ones I have.. and extra would be handy)

[julianf]

i meant 16 amp on the 240v side of the transformer - eg 16 x 240 = 3840w

4 batteries would be the easiest option (i wouldnt need 4 chargers though, would i?) but i dont know what sort of duty would be good.  i suspect that id want to run the job for a little while at least.

if i dont use the motor, you would be welcome to first dibs.

[knighty]

you could just use 1 charger, but you'd have to swap it between the batteries to charge them all... easier just to get some little crappy slow chargers and leave them on all the time

[photoman290]

if the batteries are all the same age and type you could charge in parallel.

[julianf]

Ive been thinking - would an old arc welder be a suitable power supply, if rectified to DC?

[Tony]

Might manage it with an old MIG, they have rectifier diodes in for DC output?

[Tony]

Some other possibilities - a scrapped powerful UPS, some of them are 48V internally for 4x 12v batteries, or a MOSFET PA amplifier, they often have a huge torroidal transformer in and rectified DC rails - though unlikely you'd find a 4kW one you might be able to parallel a couple up?

[photoman290]

Ive been thinking - would an old arc welder be a suitable power supply, if rectified to DC?

may do if you stick to the duty cycle. usually 25% so you would have to have some way of switching it  off for 45 minutes in every hour. putting it in oil would help.

[julianf]

I have not got the motor yet.  I guess, maybe, i should just go the battery route, as its easy, and get the rest of the unit together, before spending too much time thinking about spinning it?


Dont suppose anyone has any hydraulic rams knocking about, do they?  I need a push/pull one, and, i reckon, about 7 tonnes ish.

(going by a 4 tonne log splitter uses a 2.2kw motor, and a 5.6 tonne unit has a 3kw motor... if this one is 3.7kw, 7 tonnes plus?)


I totally dont know what im doing with hydraulics, by the way! ; ) But that's the way i generally start stuff.


What im wanting to build is a press / extruder for making briquetts out of sawdust.  Either somthing like this -

http://www.youtube.com/watch?v=EauczlfGAio

Or somthing much simpler, making larger units.

I have in mind 9" x 12" x 4" (ie slabs) with a few holes through the short side.

The door of our rayburn is 9" wide, and the firebox is a bit over 12" deep.  I figure that, if i could press blocks, and then load them flat, rather like you would a pizza into an oven, then i could load one, let it burn (with the flames coming through the holes), and, as it burnt down, load another on top.

If i were making larger blocks like this, i wouldnt need to automate.

[julianf]

Right,

Ive got the pump here now.  Its somewhat heavier than i was expecting!

The gear pump is one of these -

http://www.hy-power.com/browprods.asp?mid=10116&wht=BOSCH+REXROTH&pg=man&offset=270&pid=36713&oid=10535&sro=270


Ive even found the most confusing datasheet ever that seems to cover the pump -

http://www.boschrexroth-us.com/country_units/america/united_states/en/Products/bri/Products_and_Catalogs/bosch_branded_products/literature_downloads_pdfs/a_downloads/pdf_erl/gear_pumps_and_motors_specifications.pdf

part number is listed on page 92 (of the non-searchable document!) and one of the columns reads "5.5 cm3" - so i assume that is displacement per revolution?

But that is about as far as ive gotten so far!