OP
dcyrilc
Super Member
I've noticed, since I've been reading here, that most of the posts talk about power beyond. I believe this relates to OC systems. Are most newer tractors OC/CF?
General hydraulics question
- Thread starter dcyrilc
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kennyd
Advertiser
Yes, Pretty much all of the newer CUT's are OC, some BIG AG tractors use CC systems...
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OP
dcyrilc
Super Member
What are the advantages/disadvantages of OC vs CC systems?
kennyd
Advertiser
Not to blow you off...but with my finger pecking it could take me hours to type something that still may be less than 100% accurate because I am not very familiar with CC systems.
I will Refer you to the Army Hydraulics Manual and The Principles of Hydraulics for explanations of both systems.
OP
dcyrilc
Super Member
What I was actually wondering is if OC systems were cheaper for mass production of the smaller less expensive tractors or something similar. Basically, I was wondering if it was an economic choice or if there was a major advantage to using the OC systems in the CUTs. Not as much curious of the details, as I realize that an explaination of such would be quite lengthy. I also realize that this answer is probably mostly opinion as I don't expect to get an answer from company CO/XOs that would have actually make those decisions.
kennyd
Advertiser
I do believe the OC systems are cheaper...
OP
dcyrilc
Super Member
That would explain the wide usage. Economics can be a great motivator for some of the things companies do, and ultimately, the bottom dollar is what determines if you stay in business.
AKKAMAAN
Veteran Member
OC= wasting energy, not operator friendly on mobile equipment (response on controlvalve depends on load pressure and actual pump flow) Takes a more skill to run a crane with 3-6 actuators simultaniusly....
CC=responds much better on controlvalve operation more independent on load pressure, waste less energy, easier to operate the above mentioned crane...
OP
dcyrilc
Super Member
And your opinion on why most, if not all, the new CUTs use OC/CF?
AKKAMAAN
Veteran Member
Sorry I do not know what CUT is supposed to abbreviate?
Generally this is the case...
OC/CF is MUCH cheaper to manufacture, like 25% of a modern CC/CPU or LS system.....
OC trade off is poor manouverability and poor energy economy
OC/CF mainly used on cheaper equipment and/or where system dont use a lot of energy....like a hydraulic transmission......
CC/CPU-LS is used on advanced equipment wher operator use a crane (simultaniously precision manouvered actuators)
See these videos
Excavator
Harvester
Forwarder
kennyd
Advertiser
AKKAMAAN
Veteran Member
Thank you Kennyd!!
Back to way OC is used...
As I said earlier....a CUT sold new for X$$$, cant justify a 10-20 higher price with a more advanced hydraulic system that cant be paid off in more/better efficiancy....
But some smaller service systems that dont take a lot of energy are made CC with a fixed pump.....example for lubrication, servo systems for shifting automatic transmissions...etc..
OP
dcyrilc
Super Member
Thank you to everyone for your valuable information.
I'm new to tractors and new to working on hydraulics, even though I've run heavy equipment for 25 years.
The 30 year old 68 HP (50 HP PTO) tractor I recently bought and am working on has a CC/CP hydraulic system. The backhoes and trackhoes I've used seem to be also.
As I've read on here over the last month, it seems as though nearly all the equipment on the forum have OC/CF hydraulic systems. I have been trying to figure out the reasoning for this. It would appear that it is a simple matter or economics, but helps me to understand the world of tractors which I am becomming a part of a little better.
Thank you again for all the info!
I'm new to tractors and new to working on hydraulics, even though I've run heavy equipment for 25 years.
The 30 year old 68 HP (50 HP PTO) tractor I recently bought and am working on has a CC/CP hydraulic system. The backhoes and trackhoes I've used seem to be also.
As I've read on here over the last month, it seems as though nearly all the equipment on the forum have OC/CF hydraulic systems. I have been trying to figure out the reasoning for this. It would appear that it is a simple matter or economics, but helps me to understand the world of tractors which I am becomming a part of a little better.
Thank you again for all the info!
jenkinsph
Super Star Member
Cyril,
Yes it is a matter of economics, a good example would be to look at the Sunstrand 8 piston variable volume pump diagrams and compare it to a two section gear pump. Lots more machining and small parts in the piston pump.
The 2240 when new was offered with either a power reverser or hi low options. Do you have either of these options on yours?
Yes it is a matter of economics, a good example would be to look at the Sunstrand 8 piston variable volume pump diagrams and compare it to a two section gear pump. Lots more machining and small parts in the piston pump.
The 2240 when new was offered with either a power reverser or hi low options. Do you have either of these options on yours?
OP
dcyrilc
Super Member
Just independent PTO, MFWD, and FEL. No Hi/Low or Reverser. It didn't even come with any rear remotes. I'll add those myself later. The only major problem it has is that it appears to have had steering damage and had the power steering housing replaced with a used unit with very extensive wear (the rest of the tractor only shows minor wear). I'm in the process of completely rebuilding the power steering housing.
Tim Dawson
New member
I have a massey ferguson 2135 and thought it was a closed system. Someone said it is an open system because it has power beyond. Do the cylinders hold in place when in nuetral because only the inlet is open to power beyond or resevior when in nuetral? May I have a LS system?
kennyd
Advertiser
Double checking me? Good-I need it sometimes.
The type of system , OC or CC has no effect on cylinders holding when the valve is in neutral, that is done by the spool design inside the valve. Valve's will say "work ports blocked in neutral", or Open Center, Tandem Center (what we really want-But Open Center has become the norm...) or the like.
