So with roughly 2 1/4 times the fluid needed for the 3" vs the 2", your saying that the fluid speeds up that much as that you would not be able to notice the difference? I agree that the fluid speeds up, but more than double?
Brian, I never said there would be no noticable difference. The cylinder would push more fluid out the restrictor meaning higher psi. There is a whole lot more happening in a hydraulic system than in the cylinder. Nobody is taking this into consideration.
Just good old common sense, and that is not bragging about ones degree, because I am not impressed.
JJ, in a past post in the Power Trac section, you repeatedly badgered me about my qualifications until I posted them. All I was asking is for you to do the same. I will take a guess at your qualifications since you won't post them. You have very little actual experience on hydraulics. You went to Brendan Casey's website and did some reading, you still do. Actually, when questions are posted, you refer back to his website and quote almost verbatim. If you were in school, you would be expelled for plagerism. I hear you quote one of his recent articles, which I read in a trade paper, Machinery and Lubrication. He says that worn piston seals can not cause a cylinder to drift because of the differing volumes in the 2 sides of a cylinder. However, how come almost every drift issue is either solved or greatly reduced by replacing worn piston seals? Doesn't make sense does it? How many tractor owners on this site have had drifting problems completely eliminated by changing nothing but piston seals? So it defies common sense. Just like a bumble bee being able to fly defies common sense and every engineering principal known to man, but, they do fly. Maybe you need to consider real world experience into your common sense equations.
Now, looking at your last post, shown below, you are again incorrect. If you only put a restrictor inline, PSI would also change. By changing the orifice size, you would cause a change in the resistance to flow which would of course cause a change in pressure. You are not taking this into consideration.
The area on the inside of the cylinder will determine the time it takes for the cylinder to extend or retract. GPM's are a variable, and size of the cylinder is a variable, also the length of the cylinder. This will all correspond to time it takes to open and close. If you only put a restrictor in-line, you change GPM's.
Pressure in your above scenario would also be variable. There is also way more to a hydraulic system than the cylinder. When you install a restrictor, regardless of the cylinder size, you change pressure and flow throughout the system. If you take a system with a .030" restrictor, remove a 2" bore cylinder and install a 3" bore cylinder, the cylinder would not be 2 1/4 times slower. Pressure would naturally be increased because of the increased flow which would help increase the rod speed. The area of the cylinder will not be the sole factor of cylinder speed, as you stated above. It's only half the equation, GPM will be the other half. Actually, a little less than half. There are also frictional losses to take into consideration.
Now, like I previously stated, I have seen the .030" restrictor in 2" bore cylinders and 3.5" bore cylinders. There is not as big a difference in speed as you would think. There are variables elsewhere in the system that keeps the speeds a lot closer than you think. With a restrictor in a system, pressure is increased. With the higher pressure through the same given orifice, you would have an increase in flow. This helps bring the rod speeds between the 2 cylinders a lot closer than you think.
Finally, I am not a know it all or ever proclaimed myself to be. I admit when I am wrong, openly and honestly. Here, I know factually, that I am not wrong. I not only have been schooled in the theory, but probably even more importantly, I have the real world experience.
