replacing a single acting cylinder with double acting

Tx Jim · Sep 17, 2015

J_J said:
There you go again. You seem to misunderstand just about everything I say.

I never said he had an SA valve, even if the same valve can contains both DA spools and SA spools.

He said he had a SA cyl and I wanted to know if the valve was an SA valve and if it was not I would tell him how to use the SA cyl on a DA valve, of which there are two ways.

I know very well how to use a DA valve on a SA cyl.

I didn't misunderstand the question you asked or just about everything you state but the point is you don't like anyone disagreeing with what you state. I never stated or implied that YOU STATED that OP had a SA valve. Maybe you should re-read what I posted?????

thendrix · Sep 17, 2015

Before we get world war 3 started here please tell me the difference in a single and double acting valve.

Tx Jim · Sep 17, 2015

No world war 3 on my part. FYI Bore of the factory cylinder on a 1219 is 2.254''s while shaft diameter is 1.875''s
SA cylinder has one hose attached to it & with hyd pump pumping applying hyd pressure extends rod from cylinder then moving control lever opposite direction weight from implement closes cylinder IE forces rod into cylinder. DA cylinder will have pressure applied on one side or the other side of piston which forces piston one direction or the other depending on which way control valve is moved IE hyd pressure up & hyd pressure down. SA cylinder rod can float in & out of barrel while DA cylinder rod/piston is held in place unless control valve has a float position that is utilized.

thendrix · Sep 17, 2015

Ok. I do have a DA valve and a SA cylinder. There's no float circuit in the valve

J_J · Sep 17, 2015

If you want float, you need a single spool valve with PB and float and run the B work port hose to tank.

Tx Jim · Sep 17, 2015

If I'm not mistake factory lift cylinder on a 1219 will float when used on a regular DA valve

J_J · Sep 17, 2015

A single action valve will have one work port per spool.

DA valve will have two work ports per spool.

2 SPOOL 10 GPM CESSNA 31512 OC SA VALVE

2 SPOOL SA CESSNA CONTROL VALVE 30 GPM

However you can use a DA valve spool as a SA valve spool, by plugging the B work port or running the B work port flow to tank.

A SA cyl will float if the lowering position is used /held open.

For SA float, you could bungee the lever for lowering