Log Splitter Hydraulic Plumbing Question

[Rob in NC]

ive got a question on log splitter plumbing. Im rebuilding my old Northern log splitter and ive basically replaced everything but the original cylinder and the pump - this rebuild "evolved" as it went like everything. I know enough about hydraulics to be dangerous as ive been around the farm most of my life but theres specifics here i need help with. Im not happy with my cycle time (14 seconds) i never timed it before my rebuild but i feel like it was faster before and i thought i improved the new plumbing to move it faster but obviously something is working against me. Here is what i have so you technical minds can diagnose my setup:

- 13hp honda engine
- 16GPM Haldex pump
- 1-1/2" supply line necked down to 1" to plumb to pumps 1" nipple
- 3/4" high pressure line (fitting on pump is 1/2")
- 3/4" cylinder top line
- 1" return cylinder line to valve
- i added a 25GPM prince auto return so the 1" cylinder return goes into this then comes out in a 1" return to 1-1/4" hydraulic tank filter (you can see this in the pictures it will make more sense)
- there is another prince valve in series with a 3/4" return line tied into the 1" return line that steps up again also into the 1-1/4" 60 GPM filter back to reservoir tank which holds 28 gallons. i stepped the tank size up to help with cooling since 16 gallon is recommended minimum with this size pump. 
- my cylinder is a 5" bore with a 2" ram rated at 25 tons. 

couple things i tried to do here: I stepped up all the line sizes to reduce heat and friction and help improve flow. The stock high pressure line from the pump to valve and valve to cylinder were all 1/2" originally. Is this larger 3/4" line i now have here robbing speed from my cycle time? from what i know about fluids in general this is my first thought (smaller line more pressure but less flow)
i was told the return line on the cylinder flows the most fluid at once so i brought this up from a 1/2" to a full 1" trying to improve flow. 

another question: again i dont do alot of hydraulic work so i was talking to the counter at the hydraulics store trying to buy thread sealant and they told me i dont need any sealant on my threads in a hydraulic system that they dont even sell such a thing. Well all my fittings are NPT and i put some white PTFE pipe dope on everything anyway cranked it down tight as i felt comfortable left it over night and just about everyone leaked the next day when i tested it. whats the recommeded way to seal a NPT hydraulic thread fitting?

[doc henderson]

so, a larger line will reduce friction even if at the end you have to reduce back down.  elbows create restriction and a larger one has less.  also, the flow is reduced in linear say feet per second, but overall flow is the same.  a system purged of air has to have the same flow out as in.  If you had a 16-18 hp engine and a 28 gallon per minute pump, your system would be the same as mine.  all return typically goes thorough the valve, and I got a dump valve so on return it opens and creates a direct line to the reserve tank, bypassing the valve and the heat that can wear on them.  because the rod is taking up volume on the rod end of the cylinder, you put more oil out the back on retract, compared to going out forward to split.  Are the valves in series new?  I wonder if the first one has to be a power beyond?  is that an auto cycle valve?  A good resource is James at ezsplit.  he sells parts and use to market his own line of splitter.  He seems to enjoy talking about splitters and is knowledgeable.

[doc henderson]

does it have the expected splitting power?  do you have an inline pressure gage between the pump and valve?  looks like a nice splitter.  to get the most gains, you need all the components to be sized for each other.  i.e. pump, engine, valve.  that is a big cylinder.  so, it takes a fair volume of oil in gpm to make it move.

[sawguy21]

That is about right for a 16 gpm pump, you could go to 22 gpm but now you need more power to maintain the speed.

[Hilltop366]

Did you check your engine speed?

Could be running slower than the old engine.

Also the old engine could have been running a bit over speed.

[doc henderson]

I split mostly 16-inch logs.  Mine is a 32-inch cylinder, and yours look similar.  what is the length?  I have 8 inches of stops so the retract and move to the log if full retracted is less.  i.e. 24-inch split range with the stops.  they are spring loaded so come off if need without tools.  I got a deal on that cylinder as there were 3 of them special ordered, and I bought one.  wish I had bought all 3.  paid 180 bucks back then.

Is your pump set to 2500 pounds?  that should get you to 25 tons.  you piston surface area is about 20 (19.625) sq. inches.  20 x 2500 = 50000 pounds or 25 tons.

[doc henderson]

some pics of mine.

[Rob in NC]

I am familiar with the dump valve and the larger pumps/2 stage pumps increasing speed and I may do those upgrades in the future but I was happy with the speed I had in it before the rebuild. I wish I had timed the cycle before I broke down the old splitter because I'm going on memory but I feel like it was faster it seems painfully slow now and never bothered me before. I'm trying to determine what part of this plumbing would have worked against the original cycle time and caused me to regress. 

[Rob in NC]

so, a larger line will reduce friction even if at the end you have to reduce back down.  elbows create restriction and a larger one has less.  also, the flow is reduced in linear say feet per second, but overall flow is the same.  a system purged of air has to have the same flow out as in.  If you had a 16-18 hp engine and a 28 gallon per minute pump, your system would be the same as mine.  all return typically goes thorough the valve, and I got a dump valve so on return it opens and creates a direct line to the reserve tank, bypassing the valve and the heat that can wear on them.  because the rod is taking up volume on the rod end of the cylinder, you put more oil out the back on retract, compared to going out forward to split.  Are the valves in series new?  I wonder if the first one has to be a power beyond?  is that an auto cycle valve?  A good resource is James at ezsplit.  he sells parts and use to market his own line of splitter.  He seems to enjoy talking about splitters and is knowledgeable.

So what your saying here is line size doesn't effect speed correct? This is what I wasn't sure about

[barbender]

So, are you running a 2 stage pump?

[doc henderson]

tell me about the auto cycle valve and the valve in series.  are these new and were they present on the original?  I use tape or pipe dope on npt.  did we lose your pictures?  i think you need the auto cycle valve to have a power beyond port for the second valve.  is it to raise the table?

If you had a restriction, it might fix a problem and run faster.  but again, you size everything for the flow you get from the pump and motor combo.  and rated for the max pressure.  I run mine at 3000 psi.  I have the 20-gallon tank.  I have 28 gpm 2 stage pump and an 18 hp engine.  only needed a 16 hp but this one rarely draws down and I often run just above idle.  So, line size could impair speed, but above a certain size (sized for the pump output), it will just run as fast as the pump can push it, and not faster.

[Rob in NC]

The auto cycle is new and it has power beyond. The lift table has a flow limiter and it works fine. I did not have these on the original. 

[doc henderson]

did you plumb in the power beyond and run that to the next valve?  In true series you may bleed off some flow to the second valve when not in use.  I think when using the power beyond, only one valve will work at a time.  I do not have this but have spent hours thinking about it.  My son is now 23 but when we built the splitter, he was 12 and I did not want automation.  how long is your cylinder?

[Hilltop366]

There are hydraulic speed calculators on line that you can put in your specs and get an idea how fast it should be going.

[doc henderson]

I spoke with James for the past half an hour, solved a few world problems and talked hydraulic equipment.  He is 78.  He said for a 16 gpm pump, the half inch lines are fine, so not much if any gain by increasing line size.  The pump can go to 3000 psi for more pressure.  the pump you have could run off an 8 hp motor so you have plenty of ooomf.  A man next to my own heart.  He said to put a tach and check rpms.  He said you need to plumb with the power beyond plug and have two lines coming off, one to the second valve and one to return to the tank.  He said if using a restrictor, it can generate heat and be hard on the pump, and a diverter is better to adjust speed without a restriction.  If in series, you may be losing flow to the table valve if it is passing though.  He said if you ran a 22 gpm pump through a series of 1/2 inch lines it would be fine but generate more heat. Is the pump old?  can you check PSI.  He said as have others to check rpms on the motor to make sure it is 3600, and not 1800.  or even just running 3200 would affect the flow.  his site is split ez P & J products (Penelope and James).  You can call him, but he will have all these questions and talk a few politics.   (661)-248-5270.  It is a mom-and-pop shop, and if either has a Dr. appointment, no one will answer the phone.

[Rob in NC]

You're not the first person to tell me to call James. Sounds like hes the guru I'm just gonna call him and spitball what I've got with him and see if I can learn something. Thanks for the help doc

[doc henderson]

I would try to get answers to his questions first and make the most of your time.  Tell him Ol Doc Henderson sent you.  ha ha

[Old Greenhorn]

It might be helpful to point out that regardless of your hose diameters, you connections are likely the smallest part of your flow path and serve as the restrictors. You could have a 2" pressure line, but if it is feeding through a 1/2" port, you won't increase your flow much. You will reduce your friction loss in the line though and increase your fluid capacity. Those small port restrictions are also where your heat builds up because of the increased force nd friction to get through the small opening.
 It's not important here in a low pressure system, but the higher the pressure, the smaller the hose they try to design for. This is because smaller hose has less wall and cross section and there is less force on those walls trying to burst the hose. I used to regularly test hoses to 27,000PSI, but they were 5/32-1/4" ID hoses, up to 50' long.
 I wonder if we can get @fluidpowerpro to lay in some of the engineering principals here. He knows his stuff and may not have seen this thread yet.

[Rob in NC]

It might be helpful to point out that regardless of your hose diameters, you connections are likely the smallest part of your flow path and serve as the restrictors. You could have a 2" pressure line, but if it is feeding through a 1/2" port, you won't increase your flow much. You will reduce your friction loss in the line though and increase your fluid capacity. Those small port restrictions are also where your heat builds up because of the increased force nd friction to get through the small opening.
 It's not important here in a low pressure system, but the higher the pressure, the smaller the hose they try to design for. This is because smaller hose has less wall and cross section and there is less force on those walls trying to burst the hose. I used to regularly test hoses to 27,000PSI, but they were 5/32-1/4" ID hoses, up to 50' long.
 I wonder if we can get @fluidpowerpro to lay in some of the engineering principals here. He knows his stuff and may not have seen this thread yet.

Yes, all of this I understand the friction points come from the tightest areas the 90s don't flow nearly as well as 45 or straits. The reason I made the lines and tank bigger is more for hydraulic cooling and for future expansion like for instance, I feel like I'm going to go to a larger pump then 16 at some point since I have a 13hp engine and I won't have to resize the rest of my system for it I'll already be at that level and basically other than cost I felt like the bigger the better when it comes to plumbing the only thing I wasn't sure if I was hurting myself when it came to pressure loss when going bigger on hoses. I feel like ultimately I'll end up at a two stage 22 GPM and a dump valve but I wanted to push that additional thousand dollars down the road a little if I could.

Sounds like the general consensus from all the above comments is there is really no measurable pressure loss from hose size - fluid in equals fluid out no matter how big the hose (within reason)

[doc henderson]

yup!  you have a foundation for a heck of a machine.

[Rob in NC]

There are hydraulic speed calculators on line that you can put in your specs and get an idea how fast it should be going.

Based on this calculator:

https://logsplitterplans.com/calculators/hydraulic-cycle-calculator.htm

I should at 14.2 seconds I timed it at almost 14 which could just be a timer discrepancy so it sounds like I'm right where it should be set up which makes me feel a little better. I swear it seemed faster in my old set up but again I never actually timed it so I'm going off memory. I wish I had timed my "before" cycle.

Thank you that was a good idea. I didn't know those existed.

[doc henderson]

If you cylinder is long, get some stops.  You have a heck of a machine with good cycle time and all the power you will ever need.  Prices are way up, so enjoy it till your find a deal on a 22 gpm pump.  You have the hose infrastructure in place.  I bet mine in not much faster than that.

[Al_Smith]

I have no idea what the big deal is with cycle time .My home built uses a five inch Parker-Hannifan industrial cylinder rated at over 4,500 PSI driven by an 11 HP Briggs engine and a 16 GPM two stage pump set a 2750 PSI .I seldom run that noisey contraption much above half throttle because it will out run me .However it will split anything and seldom shifts to high pressure lower volumb .Cycle time might be a big deal if you are  25 years old,three times that it's a better option than an axe .

[Rob in NC]

I have no idea what the big deal is with cycle time .My home built uses a five inch Parker-Hannifan industrial cylinder rated at over 4,500 PSI driven by an 11 HP Briggs engine and a 16 GPM two stage pump set a 2750 PSI .I seldom run that noisey contraption much above half throttle because it will out run me .However it will split anything and seldom shifts to high pressure lower volumb .Cycle time might be a big deal if you are  25 years old,three times that it's a better option than an axe .

Cycle time is directly relative to "productivity per hour". Some cases this doesn't matter of course depending on your needs but in my world i work a lot at my day job and the farm and the mountain of tasks that come with owning it and keeping it in the state i want it to be at (grass mowed, horses fed, pastures cut, fish fed, firewood split, garden watered etc.) eat up a lot of the small amount of "my time" i have so the quicker i can do the chores that need doing the more things i can get accomplished. Trust me i don't agree with the fast paced life the world pushes us into i think i would have been happier to live at the pace of the 1800's American but as you know in order to have anything material in todays world you have to work a lot and work hard to keep up. Makes life go by at a lighting pace which i don't like either i dont feel like i should be 40yo yet in 30 days. 
Trust me i have about 15 different axes (councils, plumbs, collins, true tempers, various mauls and a couple i have no idea) and i still enjoy using them to split when i have time to slow down which does happen sometimes but this project was more centered around the times when i need to make it happen in a timely, easier on me, manner i use the hydraulic splitter option so cycle time plays into this and i know i can spend the money and have one that cycles in 6 seconds but i've always been a "weigh your options middle of the road" type of person. I don't need $10k in a log splitter to split 5 cords of wood a year for the house either so im trying to make the most of what ive got and decide where to stop the cost bleeding in this project and call it good enough. Also truth be told probably 60% of this build was aimed solely at ergonomic improvements i got tired of running a splitter that was 12" off the ground with no lift arm leaning over for hours on end and wrestling rounds - i dreaded splitting wood. I've now got it at 32" to the beam and a full hydraulic lift table for my rounds plus ive got a 48"x48" flip top outfeed table - No more bending over! hitch from either end, full axle with leaf springs for highway travel, fenders to keep mud off my engine, a light tower for night work and double the fluid capacity in my tank for cooling. So regardless of cycle time were moving up in the world. Cycle time would be icing on the cake at this point.. However I just felt like my time got worse based on what i remembered and i wanted to make sure i didnt do something wrong i certainly didn't want to regress in this area. 

[doc henderson]

I will be 64 in October, and you are a man next to my own heart.  I love improvements, but also do not want junk that can snag going through a wooded area or look cobbled.  I added fleet wiring to my splitter so it can charge my 12-volt power to a conveyor.  It can all run off my truck and I could even jump start my truck from the splitter or conveyor.  I even bought copper tubing to wrap around the car muffler on the rig, to reduce now and allow for a way to heat water in the field for hot chocolate or tea/coffee as desired.  Lots of good ideas.  Never got that installed.  considered the auto cycle now that my son is older.  Have the dump valve but not yet installed.  see the shade tree mechanic thread.  busy with life as well.  I have enjoyed this exercise.  Doc.

Shade tree mechanic! Whatcha workin on. - Page 2 (forestryforum.com)

ongoing splitter and conveyor upgrade. - Page 2 (forestryforum.com)