Certification of Full Pressure Ram

[JeremyCuss]

The rules say,

"Custom made components, or parts operating above the suppliers maximum working pressure, must beindependently tested and certified at 120% of the maximum system pressure available at that point."

Please can someone tell me of a person/organisation who can provide this service. I have a full CO₂ pressure ram that needs certifying. I also need to know the pressure to which it needs testing. As I will have a 1000psig bursting disc, this would seem to be a sensible test pressure. It is also about 120% of the likely maximum system pressure. I am happy to be guided by others.

[maddox10]

Is it the steel 100*140 you got a few years back?

[JeremyCuss]

Wow! You've got a good memory. It was made for me by Mario deJongh about 10 years ago.

[maddox10]

That ram was build to cope with 105 bar/4500psi hydraulic, static pressure.

[JeremyCuss]

Thanks for that information. I guess that I need a piece of paper to say that. I really don't know what proof is required of me by those inspecting my robot.

[Liftoff]

Wow! You've got a good memory. It was made for me by Mario deJongh about 10 years ago.

You're talking to Mario (maddox) As for certification, I don't know if anybody certifies custom components....for sure it will be difficult to find someone who would risk testing an unknown component and giving it a certificate unless they are really confident the component is well made etc...

[JeremyCuss]

I guessed that it must be Mario. No-one else would know the dimensions of my ram. There must be other roboteers running full-pressure rams. Perhaps they could tell me whether they had any problems or need for certification.

[maddox10]

My certification capability evaporated with the change of job earlier this year.

[emisnug]

HPAC (http://hpac-armourlite.co.uk) might be able to help you with pressure certifications. They're running a little slow at the moment because Trev's in hospital, but they've certified some of my old pressure components to 300 bar before.

[JeremyCuss]

Thank you Robert. That is an excellent solution to my problem. I have rung them. They will test it next week and can do it while I wait. They will provide a certificate. What is more they only charge £40 and obviously have done quite a few rams for Robot Wars in the past!

[emisnug]

Thank you Robert. That is an excellent solution to my problem. I have rung them. They will test it next week and can do it while I wait. They will provide a certificate. What is more they only charge £40 and obviously have done quite a few rams for Robot Wars in the past!

Great to hear! Yes, HPAC have been around for a while. Very nice bunch of guys - if Trev's there, ask him about his lawnmower tank! (I know him from tournament paintball)

[emisnug]

Hi Jeremy, did your ram get certified in the end? Trev mentioned Robot Wars parts but I didn't catch him before he went off again

[JeremyCuss]

No, the ram didn't get certified. The valves were pressure tested successfully up to 90 bar, but the ram leaked very badly around the seal. I am planning to replace the seal, but I haven't done so yet, because of a series of problems, which I am overcoming one at a time. I will then bring it back to HPAC for testing.

[emisnug]

That's a shame. O ring sealing is never fun, and rarely right on the first or second try.

What pressure are you trying to seal? I'm alright with reciprocating O Ring glands

[JeremyCuss]

I'm trying to seal full CO2 pressure - maybe 60barg. I'm interested in the reciprocating O ring glands that you mention. They sound like the sort of O rings used in my old 16 barg Norgren pneumatic cylinder. They were made with very soft elastomer and appeared to have a lip to seal the pressure. This old cylinder had two seals, but I only need one, as the pressure is at one side of the ram only. I have no idea where to get such seals, nor what the best material of construction would be. Any help would be appreciated.