Low pressure cylinders/high pressure systems

Thank you Roger, your experienced input on this issue is appreciated.

We are trying to put off builders from this practice but not outlaw it as clearly there are builders who have, or have access to the expertise necessary.

Christian, even on M2, the ram was modded with new tie rods. The pneumatic cushioning is just about useless with the high velocities, so the next stage is to replace the top cap with a machined 6082 T6 block just like the base. Whilst it has yet to fail, continued use can only weaken the cast top end.

Paul

Hmmm, I didnt know that...

is there any cushioning that will not freeze up like rubber or something like that

The dynamic cushioning on WBCs ram works very well, it is the only system that I would consider using, and it is standard on good quality cylinders.
But the end cap materials and tie rods must be strong enough to handle it.

Our new HP- jack is constructed as a pulling cylinder ( tube from an old 100 mm bore FESTO LP cylinder, same quality as mentioned above from roger) on the end cap we use a hydraulic shock absorber for end cushioning. Tie rods are 12 mm 12.9 threaded rods, end caps machined from 7075 ali

regards
helmut

If its any use to anyone we use solid nylon bar
machined to fit in all three of Bulldogs cylinders

Was Spawns cylinder a 10 bar at 70 bar? Im still reading up on pneumatics and thats ringing alarm bells for me.

What about 10 bar cylinders at 16 bar? What needs to be done to make them safe?

The answer to your question is in the first sentence of this thread, and strengthening rams is discussed in detail throughout this thread- worth reading- no point in repreating whats written above.

Im getting an 80mm bore 160 mm stroke 10 bar ram. As a first go for someone who has never used pneumatics before, using a ram at full pressure isnt sensible. As it is, at 10 bar it can lift half a tonne. I was wondering as to whether operation at 16 bar would involve less extensive modification.

Replace the cast ends and the tie rods.