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Need your help please.

We have two air cylinders (to be filled up to max 200 bar). We have had mixed information if we require or not CE certification because of the small volume of the cylinders.

The one air cylinder has a volume of 10.5 cm3 (0.01/Lt and the other has a volume of 112 cm3 (0.112/lt. The pressure we advise the customers to fill them with is 80- 120 bar and the maximum valve pressure recommended by the valve manufacturers is 200 bar. The small air cylinder is made of strong stainless steel and the bigger from strong steel.

We get conflicting answers to our requests about having or not certification. We are told that air cylinders under 0.450 liter volume don't require certification.

Some customers ask us if the cylinders are compliant with the EU Pressure Equipment Directive 97/23/EC and the Pressure Systems Safety Regulations 2000.

Could you please advise accordingly as we are not sure what is legal. I personally have read the directive but still can't understand it.

RE: PED97/23/EC

It depends what the purpose of these cylinders is. A cylinder can just be a pressurized vessel or it is a component to move a certain load. I suppose when you talk about air cylinder you mean a cylindrical tube with a piston and a piston rod, correct? If so, then these components do not automatically fall under PED. Section 3.10. is the one you have to lool at: "The following are excluded from the scope of this Directive: equipment comprising casings or machinery
where the dimensioning, choice of material and manufacturing rules are based primarily on requirements for sufficient strength, rigidity and stability
to meet the static and dynamic operational effects or other operational characteristics and for which pressure is not a significant design factor.
Such equipment may include:
– engines including turbines and internal combustion engines,
– steam engines, gas/steam turbines, turbo-generators, compressors, pumps and actuating devices"
So, if you can call your cylinder an "actuating device" (as all manufactures I know do) you are o.k.

RE: PED97/23/EC

micalbrch is right. You first need to make sure under what dirctive this device falls. This has to do with the (intended) application).
From there on, we can be of further help. What's the use/goal/purpose of this cylinder?

RE: PED97/23/EC

Thanks micalbrch . Are you aware of the CO2 capsules ( they are disposable) used in air pistols to propel the pellets or bbs or air soft Bbs? We have developed a similar size capsule but instead we fill them with compressed air and they are refilable. They are cylindrical and they have a valve which opens when the pin of the pistol presses this valve and fire. Someone suggested
PED 97/23/EC Article 3 Clause 1.1(a) Para 2 where it states: -
for fluids in Group2, with a volume greater than 1 L and a product of PS and V is greater than 50 bar•L, or with a pressure PS greater than 1 000 bar, and all portable extinguishers and bottles for breathing apparatus (Annex II,table 2
but still can't understand if we are under that category to reguire or not certification. Can you explain it please?

RE: PED97/23/EC

O.k. Then your cylinder is not what I thought but a pressurized vessel. But the volume is less than 1 L and the pressure is less than 1000 bar. From what I know in this case the vessel is subjected to the Sound Engineering Practice "Pressure equipment and/or assemblies below or equal to the limits in sections 1.1, 1.2 and 1.3 and section 2 respectively must be designed and manufactured in accordance with the sound engineering practice of a Member State in order to ensure safe use. Pressure equipment and/or assemblies must be accompanied by adequate instructions for use and must bear markings to permit identification of the manufacturer or of his authorized representative established within the Community. Such equipment and/or assemblies must not bear the CE marking"

RE: PED97/23/EC

Thank you so much.
The vessels are manufactured in France for our UK based company but we also have office in France. It is rather a lengthy dealing with the French authorities, this is why I am trying to establish facts via UK establishments.
Do I understand that PED97/23/EC applies for all EU countries and "Pressure Systems Safety Regulations 2000" applies for just the UK? Reading through it seems they cover the same standards? We need to comply also with the "pressure Systems safety regulations 2000.!
Now back to the SEP. Who will access the product in order to comply with the above SEP? Do we need to ask the services of a Notified Body? The engineering company in France is ISO 9001 V 2008.
Reading I can see our vessel seems to be in category 1 on the conformity assessment of presure equipment https://www.gov.uk/pressure-equipment-manufacturer... and on production the "Equipment in Category I will be subject to your own internal production control." and for deisgn " technical documentation" Where do we give the technical documentation which I presume is part of the SEP?
Getting dizzy reading more and more....I need to establish facts ...I am not the most competent person but I got the task to investigate.
Thanks for any further help you may have for me. Regards

RE: PED97/23/EC

According to PED 97/23 air is considered as gaz group 2 (non dangerous).
The category is defined with annex 2 table 2. you have to calculate Ps.V (bar.ltr)

For your 2 cylinders you have 2 bar.ltr and 22.4 bar.ltr.

From annex 2 table 2 you can deducted that both cylinders are art3.3 because Ps.V < 50 bar.ltr so no CE marking - no NoBo

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