How much reservoir capacity do I really need?

[dstig1]

Thanks for the replies. And yes, there are some unknowns that complicate this. I have no way of figuring out how much pressure the broom really needs to run, until I build it, run it with a pressure gage in the line. At which point it it kind of too late to back-up in this case. If I had that, we might be able to work out the rest.

Some Answers
- Use pattern - my driveway and pads outside the house and shop. Driveway total is 1/8 mi or so. Long but not crazy long like some here have. I clear snow with a rear blade and it takes 1-2 hrs, longer if it is deeper or later in the season when the windrows build up and make me plow a lot more to push it back. That is one thing I am hoping from this is quicker clearing and not building up so much near the edge of the drive. It will be running much of the time while I am out there, but there will probably be pauses at times. I am assuming the broom will not work well for big snows, but I may find out otherwise. Rear blade would be the backup plan there.

- Aluminum. I cannot weld alum, so I would have to find someone who can do it, to shift to Ally. Steel is the plan.

-Pump. I already have the pump as I needed that to sort out the mid PTO drive design. It is model GP-F25-39 from this link via Surplus Center:

http://www.dynamicfc.com/documents/2019Pumps_F25.pdf

Here is what I calculated for the pump flow (gpm) vs RPM on the PTO with 2000 being the design speed of the PTO. 2100 rpm is with the engine wide open, so it is unlikely to run in that zone much (I hope...). Sweeper people say it will need something in the 12-25 gpm range

- Prime mover intended for the broom is varied. It could be set up on a skid steer but the manual shows several different configurations possible and this one was orignially set up on a 3pt hitch for a tractor. They also offer a hydraulic pump pack for the rear PTO of a tractor which then requires mounting the broom on the front and running lines the length of the tractor. Some details observed from that are that there is no radiator or fan. They do not say what the volume is, but if I had to guess from the parts diagram, I'd say around 20 Gal. Here is the manual diagram of that:

And, no, I am not buying their kit for this as I need the rear blade on the back. That was the reason I went through the trouble to set up the mid PTO drive. If I went with one tank ~15 gal and later needed to add a cooler, that could be feasible. It might also be possible to add a second tank. I'll show a few CAD images in a next post.

 

[dstig1]

These screen shots are of a single tank, 36x18x9" which equates to about 25.2 gal total volume




Alternatively I made a design with the tank split into 2 chunks to allow me to bring the SSQA plate much closer to the broom frame. These 2 were each 16x18x9" which combined comes to about 22.4 gal total volume



I can also do only one of those smaller tanks, but upsize it slightly to about 20x18x10 which gets me 15.6 gal. This would leave the opposite side clear to add a radiator later if needed....or theoretically another smaller tank to get up to 25+ gal. No photos of that, just delete the tank in the foreground of the last shot (left when facing forward) in your head.

I REALLY like the split tank or one smaller one as it greatly reduces the cantilever of the mount, plus allows me good access to connect the top of that red/brown post to the SSQA plate (this extra brace is not shown here) for extra structural beef.

 

[LD1]

Can you ask the manufacture what size tank it is they used in the 3ph option? And whether they used the same size tank for both 12gmp and 12gpm options?

 

[oldnslo]

Dave
An option to increase reservoir heat dissipation is to add cooling fins similar those found on the head of an air cooled engine. For these to work requires air movement past them which should not be a problem when moving snow since the wind is always blowing while doing that

 

[dstig1]

I'll try to call them tomorrow. I have to ask them about replacement brushes too, so a 2 fer 1...

 

[dstig1]

I finally got a chance to call them and they said 12 gpm is about what it took to run it. he said the reservoir was about 13 gal or so back when it was built. He said no cooler or anything at that set up. So I'm thinking my setup will be OK and will leave the option to add a passive cooler (no fan) later on if it is an issue.

 

[Tx Jim]

IF he goes with a 20gpm pump and the motor requires 2000 psi continuous use.....you'd lose that bet.

But there are too many unknown factors. If he drops to a 16gpm pump, and the broom only requires 1000-1200 psi....and its only under load 50% of the time as another poster suggested (only going forward....but no load while backing up).....then yea....20 gal would be sufficient

​

It appears from reading dstig1 last reply that my statement wasn't incorrect.

 

[LD1]

Not sure why you want to try and turn this into a pi$$ing match. Your statement wasnt correct or incorrect. It is YOUR opinion which is yet to be determined because of unknowns.

I dont like dealing with wild @$$ guesses. I make statements of fact. Hydraulics are very well known by many. Lesser by some who just want to cobble things together and hope it works.

There are still too many unknown variables. Knowing how much pressure is VITAL to sizing a tank. We simply dont know that.

Sure....he can run a 20 and it may be fine....but it might overheat if used continuously.

Just because a MFG used "about" a 13 gal tank with a 12 gpm pump dont mean it wasnt right. Doesnt mean things lasted if ran hard. Dont sound like they made too many of them really.

 

[Tx Jim]

LD1
I'd didn't refer to your post until you referred to my post. So you must think it's fine for you to reply stating about me loosing a bet but not it's not OK for me to reply back to you. I was replying not urinating so have a nice day.
Jim

 

[dstig1]

Well I have squeezed a bit more volume into the single tank design (on one side only) as a little extra cushion and have plenty of room to mount a cooler on the other side if it turns out to be necessary. The only way to find out the rest of those variables is going to be to finish the build and try it out.

I think odds are good it will work given the history from the manufacturer, and to your point, LD1, of them not making many, I'm pretty sure Sweepster is the biggest maker of these brooms out there. They still show similar setups with PTO pump packs for current models, so I have to assume they have it worked out over the past 40 yrs or however long they have been doing this.

Time to start getting some steel and bending up & welding a tank...