another splitter build

[origionalrebel]

my first post. i've been trollin this site for quite a while researching splitter builds and just enjoying reading about what other people in the wood heat thing are doing. great site! now for my proposed project. i plan to build a splitter/ home processor type rig so i can handle big wood alone. i plan on using a 5x24 cylinder with appropriate pump. most of the cylinders i can find have -8 or 1/2 npt ports. those splitter calculator thingys give all kinds of great cycle numbers with big pumps and 5 inch cylinders but my contention is if you can't get the oil into the cylinder because of the 1/2 port, what good is the big pump? how much flow can i realistically expect through a 1/2 fitting? how much for a -10 or -12? i'm talking real life at around 400 to 600 psi where i understand most 2 stage pumps operate until the low flow stage kicks in. how much difference, timewise between a -8 fitting and a -12? as most of you likely know, there is quite a price difference when you go for the big stuff but if it's worth it i may have to bite the bullett and go with the big port cylinder with the appropriate pump and plumbing. sorry to be longwinded but reading this forum answers a lot of questions but opens up a big ole can of worms too, lol.

 

[iowa]

Hedgerow and I were wondering the same thing. He has a 22gpm pump on a 13hp engine. To me the cycle time seems slow to what it should be. The oulet on the pump in 1" npt and I've had to neck it down to 1/2 or -8.. Everything else is -8 or 1/2"npt. Down to the ports on the cylinder. So if a 5" bore cylinder has only 1/2" npt opening what good does it do to run 3/4" hose and fittings?

 

[Hedgerow]

Yup... This should be interesting stuff...
opcorn:

 

[iowa]

I haven't looked into 5" cylinders to see if you can order with larger ports? Are 1/2" the norm?

I guess one could always grind the small ports off. Drill larger holes and weld new ports on! :msp_w00t:

 

[origionalrebel]

Hedgerow and I were wondering the same thing. He has a 22gpm pump on a 13hp engine. To me the cycle time seems slow to what it should be. The oulet on the pump in 1" npt and I've had to neck it down to 1/2 or -8.. Everything else is -8 or 1/2"npt. Down to the ports on the cylinder. So if a 5" bore cylinder has only 1/2" npt opening what good does it do to run 3/4" hose and fittings?

my point exactly iowa. i've found cylinders new as little as 199.00 but with -8 ports. the cheapest i've found for -12 ports is from spliteze at close to 500 bucks. can't see fast cycle times with a restriction like a small port anywhere on the system. i may be wrong but all i see from a big cylinder with small ports is hot oil and slow cycle times.

 

[midwest_170]

Hedgerow and I were wondering the same thing. He has a 22gpm pump on a 13hp engine. To me the cycle time seems slow to what it should be. The oulet on the pump in 1" npt and I've had to neck it down to 1/2 or -8.. Everything else is -8 or 1/2"npt. Down to the ports on the cylinder. So if a 5" bore cylinder has only 1/2" npt opening what good does it do to run 3/4" hose and fittings?

Flow is directly related to pressure. The more pressure you create in the line of a system the less flow you get. If you have a pump rated for 3000 psi and the log you are splitting requires 3100 psi, obviously you have no flow because the pump can't overcome the pressure. The pump will have a curve for flow vs pressure. A pump will have a flow rating at 0 psi, as you increase that pressure the flow will decrease, at 1st the flow change will be very small, but as you get higher in pressure the flow will start to decrease more rapidly. Example, from 0 to 1000 psi the flow might only change 2 gpm, but from 2000 to 3000 psi the flow could reduce 10 gpm. The smaller the fittings the higher the pressure drop is across that fitting. The same goes for hose. There are charts available to show this pressure drop at given flow rates, but most are very small when comparing to the total pressure of the complete system in the case of a splitter.

 

[Hedgerow]

my point exactly iowa. i've found cylinders new as little as 199.00 but with -8 ports. the cheapest i've found for -12 ports is from spliteze at close to 500 bucks. can't see fast cycle times with a restriction like a small port anywhere on the system. i may be wrong but all i see from a big cylinder with small ports is hot oil and slow cycle times.

The 4.5" cylinder with a 22gpm pump is relatively speedy, but we wondered if the 3/4" hose and orifices would increase that speed... And if so, how much?

 

[jags]

The 4.5" cylinder with a 22gpm pump is relatively speedy, but we wondered if the 3/4" hose and orifices would increase that speed... And if so, how much?

First thing I would ask is - Does your two stage pump kick into low speed without a load (log to split)? If not, your pressure is staying under 600 psi while flowing the full rating of your pump through the lines. I am sure there is a minor drop in flow, but I would bet you would need gauges to measure the difference. Just my opinion.

I have a small, fast splitter that I built with a 3.5 inch cylinder and a 16 GPM pump. Just running the ram back and forth I measure virtually nothing for pressure (has a gauge). That is telling me that at almost no pressure, I am obtaining almost full flow of the pump. It is running through a 3/8" port.

 

[Hedgerow]

First thing I would ask is - Does your two stage pump kick into low speed without a load (log to split)? If not, your pressure is staying under 600 psi while flowing the full rating of your pump through the lines. I am sure there is a minor drop in flow, but I would bet you would need gauges to measure the difference. Just my opinion.

I have a small, fast splitter that I built with a 3.5 inch cylinder and a 16 GPM pump. Just running the ram back and forth I measure virtually nothing for pressure (has a gauge). That is telling me that at almost no pressure, I am obtaining almost full flow of the pump. It is running through a 3/8" port.

Not even close... Hell, sometimes it don't even kick into the second stage when splitting... It just pops it apart at full speed... One thing I've noticed also, is even when it's in 2nd stage, it still moves about as fast as the old speeco did under no load...

 

[jags]

Not even close... Hell, sometimes it don't even kick into the second stage when splitting... It just pops it apart at full speed... One thing I've noticed also, is even when it's in 2nd stage, it still moves about as fast as the old speeco did under no load...

That being the case, I doubt that you have enough restriction to affect the flow noticeably.

 

[Hedgerow]

That being the case, I doubt that you have enough restriction to affect the flow noticeably.

The outlet on that 22 gpm pump was huge though... It made Iowa and I wonder about using 1/2" lines on it..
Would it not be better to not "funnel" it down?

Not a hydraulics expert here...

 

[jags]

The outlet on that 22 gpm pump was huge though... It made Iowa and I wonder about using 1/2" lines on it..
Would it not be better to not "funnel" it down?

Not a hydraulics expert here...

If given the option, I would use the proper port size and hose...that being said, it really doesn't matter much if you funnel it down or just size it down. Basically the same restriction, same heat, same pressure build.

Edit: and I am by no means a hydro expert. Just played with a bunch and understand fluid dynamics.

 

[midwest_170]

The outlet on that 22 gpm pump was huge though... It made Iowa and I wonder about using 1/2" lines on it..
Would it not be better to not "funnel" it down?

Not a hydraulics expert here...

The amount of pressure loss you are going from 1/2" to 3/4" is so small that you wouldn't see any change in flow rate. The pump used in this application requires high pressure and low volume. A small amount of pressure change is not going to affect the performance of the pump. Now if you were sizing a sprayer system and you were using a high volume low pressure pump, then yes fitting size would affect the flow. Just make sure your hoses and fittings are rated for your pressure and you should be ok.

 

[wndwlkr]

The more flow the faster the cycle time. biggest restriction i've seen is the 3/4 valves. if a person could find a valve with 1" ports, then match the rest of the system with 1", you would have a very fast splitter.

 

[wndwlkr]

The outlet on that 22 gpm pump was huge though... It made Iowa and I wonder about using 1/2" lines on it..
Would it not be better to not "funnel" it down?

Not a hydraulics expert here...

22 gpm pump has 1" outlet by design anything smaller is a restriction. be sort of like pluging up the exhaust on a vehicle.

 

[jags]

I'm telling ya, it ain't gonna matter much. (this is using a 16 gpm pump as a base line).
Going from 3/4" to 1/2" is gonna be a whopping loss of 12 psi in a 5ft run.
(sorry, the cut and paste data format is kinda sucky).

Or to put it differently - it will require an additional .13hp (notice the decimal point)

HOSE DATA
Hose I.D. (in.) Hose Length (ft.) Flow (GPM) Reynolds Number Viscosity Velocity (ft./sec)* Pressure Loss (psi.) Pressure Drop (psi/ft.)
.75 5 16 6,741 8.7 12 2.31 0.5

* Velocity must be less than 35 ft/s
Reynolds No. <= 2000 = Laminar Flow
Reynolds No. > 2000 and < 3000 = Transient Flow
Reynolds No. >= 3000 = Turbulent Flow


HOSE ASSEMBLY DATA
Hose I.D. (in.) Total psi Loss (inc. ftgs.) Reynolds Number Velocity (ft./sec.)* Heat Gain (BTUH) Horsepower Loss
0.5 16.2 10,112 26 381 0.15
0.625 5.5 8,090 17 131 0.05
0.75 2.3 6,741 12 55 0.02
1 0.6 5,056 7 14 0.01
1.5 0.1 3,371 3 2 0.00

 

[Hedgerow]

I'm telling ya, it ain't gonna mater much.
Going from 3/4" to 1/2" is gonna be a whopping loss of 12 psi in a 5ft run.
(sorry, the cut and paste data format is kinda sucky).

Or to put it differently - it will require an addition .13hp (notice the decimal point)

HOSE DATA
Hose I.D. (in.) Hose Length (ft.) Flow (GPM) Reynolds Number Viscosity Velocity (ft./sec)* Pressure Loss (psi.) Pressure Drop (psi/ft.)
.75 5 16 6,741 8.7 12 2.31 0.5

* Velocity must be less than 35 ft/s
Reynolds No. <= 2000 = Laminar Flow
Reynolds No. > 2000 and < 3000 = Transient Flow
Reynolds No. >= 3000 = Turbulent Flow


HOSE ASSEMBLY DATA
Hose I.D. (in.) Total psi Loss (inc. ftgs.) Reynolds Number Velocity (ft./sec.)* Heat Gain (BTUH) Horsepower Loss
0.5 16.2 10,112 26 381 0.15
0.625 5.5 8,090 17 131 0.05
0.75 2.3 6,741 12 55 0.02
1 0.6 5,056 7 14 0.01
1.5 0.1 3,371 3 2 0.00

Well??? That...
And the fact the cylinder only has 1/2" ports...
I think that's how we came to the conclusion, it didn't matter that much...
:msp_rolleyes:

 

[jags]

Well??? That...
And the fact the cylinder only has 1/2" ports...

Well...and there is that...:hmm3grin2orange:

 

[Hedgerow]

Well...and there is that...:hmm3grin2orange:

It is hell for stout though...

[video=youtube;e_KLE0yGlvg]http://www.youtube.com/watch?v=e_KLE0yGlvg&list=UUfB03KVhJRBISPufMa8F7GA&index=2[/video]

That's a white oak stick that's been in the shop for 3 years...

Cycle time ~12 seconds when cold ~ 10 when warmed up...

 

[ziggo_2]

5" cyl. 3/4" ports

I bought a 5" bore 30" stroke cylinder from northern tool last summer and it has 3/4 ports (which is why i got it). Its made by Prince, cost around $500

I plan on running a 28gpm pump so thats why i want bigger ports