Open center vs. close center

[majorwager]

JD 20-55 series utility tractors built from '65-'92 with hp ranges from 38 pto to about 100 pto all had CC hyd's with a few exceptions such as models 830 & 2040 with 3 cyl engines that had OC hyd's

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TX
Could not find data for a 2055? The earliest the 55 series was produced was in 1983 or 84. '65 was shortly after discontinuance of the 2 cylinder. So in 1965, likely they were still producing the 10 series. Acknowledged that deere did employ CC hyd in those early series 20th century tractors. My post is relevant to tractors produced today.

 

[chevy791979]

I guess I'll ask this..... What are you trying to run? What components?

 

[Tx Jim]

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TX
Could not find data for a 2055? The earliest the 55 series was produced was in 1983 or 84. '65 was shortly after discontinuance of the 2 cylinder. So in 1965, likely they were still producing the 10 series. Acknowledged that deere did employ CC hyd in those early series 20th century tractors. My post is relevant to tractors produced today.

There's no JD 2055 model. I stated ""series"" such as 20 series 1020/2020,30 series 1530/2030,40 series 2040/2240 etc.up through 55 series.

 

[Tx Jim]

I guess I'll ask this..... What are you trying to run? What components?

By chance is the question directed at me?

 

[chevy791979]

Asking in regards to the original post

 

[npalen]

"Orbit motor" is a somewhat generic term like "bandaid" I had never heard the term "travel motor" until this thread. An orbit motor would be used as a travel motor whether direct drive or reduction.

Here's an illustration of the orbit motor internals. I believe that Char-Lynn may have been the pioneer in orbit motors but not sure. The rotor rotates in an orbit.

https://images.search.yahoo.com/ima...p&sign=10ahc8r6p&.crumb=thc0suckgEI&fr=mcafee

 

[Groo]

I am trying to increase my hydraulic knowledge in general.

These youtube videos maybe more than you are looking for. I found them to be every informative

Hydraulics Math - YouTube

I am looking for something a bit more advanced than that series, or the other comparable lecture series-es I've found on YouTube.

I am wonder how the two compare with multiple section in use, precomppensated vs. post compensated, stuff like flow usage, reaction times for the variable pumps and how they compare for reliability, maintenance, etc.
For systems needing larger flows, can you combine two variables? what if one is on a hot shift and one is a direct drive, what would happen as one drops out?

I realize all this stuff is maybe a bit advanced for a tractor forum, but I figure it is worth a shot.

 

[chevy791979]

With a closed center, you normally have a priority valve that keeps oil flow and pressure for things like steering and or brakes. Also some systems have flow combiners and Regen valves that help in high flow situations.

 

[chevy791979]

For multi functioning systems, a load compisator style pump ( load sensing) is by far the route to go

 

[Texasmark]

I had 3 70-100 hp JDs and I assume all had closed center....I know the 4020 did for sure as I added a loader which required plumbing. The others I just assume.

Otherwise all my many tractors over the years of various brands had open center.

I really don't have a preference.