Hydraulic system symbols

[ak9]

Hi
A few months ago I bought a few NOS electric solenoid valves and a bunch of nos hyd. parts/fittings etc .On the valves are the symbols ( A,B, P,T)as in the attached picture. In this example... would this mean if neither "A" or "B" circuit is energized flow goes "P"pump to "T" tank ??
and does anyone have a link to a site so I can educate myself on hyd symbols and the like:confused2: .. thanks
ak9

 

[J_J]

http://www.me.ua.edu/ME360/fall05/Misc/Hydraulic Schematic Symbols.pdf

 

[wdchyd]

AK9'

This valve is open center in the de-energized position (pump flows to tank ) standard 4-way valve for double acting cyl (or motor).....Spring centered, and A & B work ports blocked also when de-energized.....

Pretty standard configuration......

 

[ak9]

JJ
thanks for the link It has helped me to figure some of what I have ... However I'm still scratching my head over a few other symbols & variables of aplications of them.. so I've studied the link and this is what I've interpreted this valve to be ... =Directional control valve (4 ports /
3 positions) is this correct?



wdchyd
What signifies that it is spring center ? the reason I 'm asking is on a few of the other sol.valves I have, the symbols P,T A,B are in different order/layout and the hyd engineer I got them from gave me a bag of springs saying" if I want to change the no spring center.. I might need these" . I've taken various ones apart and it seems that the bodies are all the same and the difference being in the valve/plunger it self ... does that seem right? \

thanks for the help

ak9

 

[mmurphy]

The symbol shows a spring symbol under the solenoid. (sideways z)You have 3 blocks. The center one shows the line (hose) hook up. The left side is shown with solenoid A. Energize A and then the left block will slide to center showing arrows are now lined up from P to B, and A to T. (will not really slide, but imagine it to) Energize B solenoid, now right block slides over to center. P now goes to A, and B goes to T.
I think it was already mentioned, but you have a 4 way 3 position tandem center valve. The 4 way comes from having ports A, B, P, and T. 3 position goes to reference of the 3 blocks on diagram.

 

[AKKAMAAN]

Eaton solenoid valve pdf

On page 5 you can see an example of a solenoid valve, and its optional spool configurations.....notice the added "boxes" that shows how valve shifts flow between neutral and end position....(box 2 and 4)...this never shows on the sign plate on the valve....

you need to decode the valve number at the manufacturers decoding instruction...see example on page 4....

 

[ak9]

mmurhy
Thats exactly what I needed to know to Picture it in my head ..thanks .. so with this type of sol.valve it is either "A" Energized or "B" Energized or none, but never Energize both "A" and "B"at the same time?
AKKAMAAN
Thanks, this helped me figure out some of the other parts I have
The guy I got these HYd parts /pieces from Knew What I wanted to achieve and he really fixed me up..


So , I think I got sol. valve issue resolved (at least in my head ) I'm sure when I go to wrench things it will be a differnt story and the fitting that connect everything will be the next challenge.. like What fittings this takes?
this sub plate has 2 "T"'s and 2 "P"'s would one of each get a plug?

 

[kennyd]

this sub plate has 2 "T"'s and 2 "P"'s would one of each get a plug?

Often they do that for flexability. You would plug the unused ports.

 

[mmurphy]

mmurhy
Thats exactly what I needed to know to Picture it in my head ..thanks .. so with this type of sol.valve it is either "A" Energized or "B" Energized or none, but never Energize both "A" and "B"at the same time?


That would be correct, make sure that you do not energize both at same time or coils will over heat causing them to burn out.
I will point out 1 more thing, you may have already figured it out, but the center block has the short dashes like a upside down T coming from A, and B meaning they are blocked from flow coming back out of them ports.

 

[ak9]

http://www.daman.com/catalog/pdf/manifolds/D03 ORFS Engineering Notes.pdf


This was informative
ak9