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Lord_Fabricator
05-22-2019, 02:56 PM
I have a large truck I am building, which due to weight, I intend to put hydraulic steering on. The pump I have is 140cc/minute flow rate, and each of the 4 pistons is 10cc, obviously that gives me a very slow travel speed for the pistons, with 10 seconds to go from full-speed to the opposite.

I read about hydraulic accumulators and was wondering if anyone has had any experience in that area.

sparkycuda
05-23-2019, 12:10 PM
Hydraulic steering is interesting. Not clear by your description of "each of the 4 pistons is 10cc". How many cylinders are steering and what is bore & stroke of them? How do you plan to plumb the circuit - what components are you using?

Ken

Lord_Fabricator
05-23-2019, 03:23 PM
4 cylinders, 10mm bore, 4mm shafts, 30mm stroke. 4mm hose coming down the upper links. The pump only has a 140cc flow rate. All four pistons are on the same valve.

sparkycuda
05-25-2019, 11:33 PM
Maybe what is throwing you off is the 140cc/min verses the cylinder size in millimeters. 1cc = 1000 cubic millimeters. A 10mm x 30mm cylinder has a volume of 2355 cubic mm x4 cylinders is 9420 cubic mm. The pump delivers 140,000 c mm/min, so all cylinders could extend fully in less than 4 seconds. In a typical steering setup, pairs of cylinders work opposite of each other - one extends, one retracts - reducing the total volume needed since the rod side has a smaller volume. I would think steering speed should be acceptable since seldom do we need to turn lock-to-lock. Does this help? Let me know if I've misunderstood your specs or needs.
Ken

Lord_Fabricator
05-27-2019, 03:19 PM
I see...I did my math very wrong...I forgot to convert...so yeah, that's plenty fast enough. Thank you.

Lord_Fabricator
05-29-2019, 01:34 AM
And now I have another question: Hydraulic lines with T-couplers in them. Does anyone do this and/or know where I can get 2mm T-couplers? I have 4 sets of pistons running in parallel, and would like to do that with a single valve, instead of a whole bank of valves.

Papy
05-29-2019, 04:16 AM
You can probably order directly from SMC (https://smcpartbuilder.com/products/Connectors/Fittings/Specialty-Fittings/M/M-Miniature-Fitting~38462) or find a local dealer

Here is the link to the SMC / M fittings catalogue (http://www.smcpneumatics.com/pdfs/M.pdf) which suits perfectly our activity.

PMD/Garden trucking (https://www.gardentrucking.com/list.tpl?cart=1559113867274460&majorcategory=Universal&category=Hydraulics) also offers a wide range of smaller fittings and various accessories you could use for such small cylinders

Lord_Fabricator
05-30-2019, 03:34 PM
Thank you, I'll have to look into that when I've got my actual computer to do the order.