tomrscott
Gold Member
Re: How do you adjust a hydraulic valve? *DELETED*
Junk,
I know this is much later and I haven't read all the posts, but I am curious as to your connection of the gauge to measure the pressure. You said:
"...is registered at the end of the hose coming off the valve when the valve is operated."
The question is, did you plug that hose with the gauge, or did you Tee the gauge into the hose after the valve? If you plugged the hose with the gauge, you are stopping the flow, and the pressure you will see is probably a pressure relief setting somewhere upstream in the system. Normally when you want to know the pressure flowing in a system, you Tee into the line to connect the pressure relief valve.
To Madref:
I too have an electronic background, and I agree with others that there is something wrong here with our understanding of this system. Think of an open center valve as a near zero resistance path, a wire. If you parallel that with a 1meg ohm resistor, you aren't going to develop an voltage (pressure) accross your resistor. The problem is that you have a short circuit path through your open center valve.
I think the best working theory so far is that the grapple is actually operating with mechanical advantage from the open center no load pressure of a couple hundred psi, which might be enough.
Sorry if this seems to add more heat than light to the question, but I do find it interesting, and yes it is an engineering thing to want to understand.
Junk,
I know this is much later and I haven't read all the posts, but I am curious as to your connection of the gauge to measure the pressure. You said:
"...is registered at the end of the hose coming off the valve when the valve is operated."
The question is, did you plug that hose with the gauge, or did you Tee the gauge into the hose after the valve? If you plugged the hose with the gauge, you are stopping the flow, and the pressure you will see is probably a pressure relief setting somewhere upstream in the system. Normally when you want to know the pressure flowing in a system, you Tee into the line to connect the pressure relief valve.
To Madref:
I too have an electronic background, and I agree with others that there is something wrong here with our understanding of this system. Think of an open center valve as a near zero resistance path, a wire. If you parallel that with a 1meg ohm resistor, you aren't going to develop an voltage (pressure) accross your resistor. The problem is that you have a short circuit path through your open center valve.
I think the best working theory so far is that the grapple is actually operating with mechanical advantage from the open center no load pressure of a couple hundred psi, which might be enough.
Sorry if this seems to add more heat than light to the question, but I do find it interesting, and yes it is an engineering thing to want to understand.