More Flow Questions

[6sunset6]

Log splitter
I have a 16 gpm pump. It has a 1" inlet yet the tables for suction say closer to 1 1/4 for 16gpm. Same for 22gpm pump is 1 1/4 inlet . Table wants a little more. I guess my question is if I use 1" hose and want to go to 22 gpm what will happen? The fpm gets way higher than recommended. What happens when that happens?

2nd Question
I am running 3/4 hose from pump to first valve and 1" return .
4.5 diam cylinder. From practical experience what would be the difference between 1/2 hose and 3/4 hose from valve to cylinder?
I am concerned with wrestling the 3/4 around in short distances.

 

[J_J]

If your valve has 3/4 ports, then use 3/4 hose. Use what ever hose size that is on the suction side of the pump.

 

[Stonehaller]

I guess my question is if I use 1" hose and want to go to 22 gpm what will happen? The fpm gets way higher than recommended. What happens when that happens?

There will be pump cavitations which will greatly shorten the life of the pump.

From practical experience what would be the difference between 1/2 hose and 3/4 hose from valve to cylinder?
I am concerned with wrestling the 3/4 around in short distances.

The velocity will get pretty high and you will put extra heat into the oil. You could probably get away with the small hose with the smaller pump, but if you go to the larger flow pump I would not recommend the 1/2" hose.

 

[6sunset6]

Stonehaller Thanks I am going to stay with 1" hose on the suction. It got pretty complicated with fittings to try and increase the hose size at the pump. I added a 1 1/4 valve at the tank with a reducing bushing to 1" on the output side. IF I have to work or upgrade I can just close the valve .
On the valve to cylinder I am still thinking. Maybe 3/4 on the ram side and 1/2 on the retract. The ram side is an easier run and takes more volume. The retract side has 2 hoses( auto valve) and folds around under the valve stand.
Then if I go to the bigger pump I just have to wrestle with one side.

 

[J_J]

Just use whatever hose size the valve has, or the pump. You can go larger, but it will decrease your wallet size.

 

[165masseyky]

Just use whatever hose size the valve has, or the pump. You can go larger, but it will decrease your wallet size.

I figure this is gonna be answered by a simple no but I am going to ask anyway.
I have 4.8gpm from my 165 MF I am using the Prince LSR 3060 valve my question is are there any tricks that can be used to increase retract speed or am I just gonna have to deal with it. I am about to start building a gas powered model that should be super fast but my son wants this unit for his part of the wood business(he is a 12 yr old businessman lol) and he asked if we can speed up the retract. Amazingly enough even with the 3.5 bore cylinder I have yet to put anything in it it wont split upto and including a gnarled piece of red oak split veritably to test the welds.90% of the time as soon as the first pop happens you can shift to high volume and let it roll. But the retract is kinda slow. It has about a 10 sec retract but with the 3060 the extend is in the low 3's.

 

[J_J]

The only way you can can increase the retract speed is to kick in some more GPM's, shorter shaft, increase rod size, and decrease bore size. Any one of those will be faster

Increase pump GPM's, and match up valves and hoses as to flow.

 

[165masseyky]

The only way you can can increase the retract speed is to kick in some more GPM's, shorter shaft, increase rod size, and decrease bore size. Any one of those will be faster

Increase pump GPM's, and match up valves and hoses as to flow.

I figured that was the answer. Is there a way to tap into my power assisted steering and if I did that would I need to add a reservoir to hold extra fluid. I know I have a lot of questions and I appreciate your help. Isn't much metal work wise that I can't handle but plumbing ain't my thing. I know I would need a valve to turn the flow to the splitter on or off from the steering pump. But how would I plumb it and would I need any other fluid restriction such as a check valve or something like that. The pump is mounted on the side of the engine and appears to be independent of the operation hydraulics.

 

[J_J]

If your steering pump has a separate reservoir you are out of luck, but if the steering pump is drawing from the same reservoir, then the two flow can be combined to increase GPM's. Perhaps you could add an extra pump for increased flow. Need to compute the HP required to power everything.

PTO pump would be a possibility. The largest PTO pump, a 9.9 cu in takes about 31 HP, and puts out 21 GPM at 2250 psi.

My Power-Trac has three hyd pumps. The 45 HP from the engine is required if all pumps are running at the same time.

 

[David Devuono]

I figure this is gonna be answered by a simple no but I am going to ask anyway.
my question is are there any tricks that can be used to increase retract speed

The only thing I can say is that my Homemade backhoe boom drops a lot faster that it goes up. That tells me that gravity will speed up a no-load return on the cylinder. So it begs the question, why would a couple of snow-plow trip springs not help to speed up the return? It appears that it is not so much the reversing of the fluid in the circuit as it is the short circuit of fluid back to the tank. I would try using a return spring before buying more hydraulics.