help please - which hydraulic pump

[ricm]

hi everyone,

I have been into R/C for a number of years but I am completely new to hydraulics. I am currently building a tipping semi-trailer, thinking of making it hydraulic as a simple installation for my first step. Everything needs to be self-contained within the trailer (pump/ oil tank/ etc) so I can use the existing wireless control installed in the prime mover.

The ram will be a multi-stage cylinder with only one port, so I think I need a reversible pump because I'm not planning on servo activated valve gear. Many of the pre-assembled pump/ motor combos seem to need 12V (Garden Trucking/ Wedico/ ScaleArt), but I'll be running 7.2V pack in the trailer due to voltage limits of some other electrical kit. I am comfortable to source an appropriate (gear)motor as long as I know what RPM is required. The extended ram will probably need around 80ml of fluid to fill it, so a pump flow rate of around 200 - 240ml per min flow rate to give a reasonable lift time 20 seconds or so. Looks like most of you guys use 10 - 12bar?

Can anybody recommend a suitable pump? Also how much extra should I allow for tank capacity to ensure no air gets in when the ram is fully extended?

Also any other advice welcome - eg. do I need a pressure relief valve? filter?



Also happy to consider any second hand stuff if anybody has stuff up for grabs.....

thanks everyone

[ricm]

also any help on where to get other bits like tubing, nipples, oil.....?? thanks

[Michael S]

http://www.wtbcar.com/shopping/index...h=20_27&page=1

They have a hydraulik system dont know if the run on 12v or 7.2v

I do know that a Leimbach pump is also made to 7.2v on order also for telescopic

http://www.leimbach-modellbau.de/

[Dieselchopper]

I am using the pump setup in the wtb link. Works well at 7.2 and 12 volt. I haven't decided what to run the truck I'm building on for voltage yet. I have two 3/4" od rams about 8" long running off of it for my wife's dump truck. I had to limit speed of pump to get a realistic rate of movement. I will be posting the build once done far enough.

[ricm]

thanks guys, that's a great help. I'll start with Leimbach as their pump has integrated pressure relief and oil tank which would make for an easier installation between the trailer chassis rails

[JDH429]

http://www.umstech.in/view_product_d...%20Accessories


Try these. Ive heard good things.

[dmess62]

Originally Posted by JDH429

http://www.umstech.in/view_product_d...%20Accessories


Try these. Ive heard good things.

I know nothing of hydraulics but it says 10 bar pressure. Is this enough to lift a trailer. I've seen some posts of the excavators and etc that run higher pressure. Teying to gather info also for future dump trailer build. Also what kind of gear motor would go with this

[JDH429]

Im 99% positive there were a few 30" long trailers around that have used the UMS pumps with Scale Art cylinders. These pumps come with the motor attached already.