Minimize NDT for EN13445 vessel

[Eric Wals]

we need to manufacture a filter (pressure) vessels but want to prevent/skip RT, due to cost impact.
Design pressure 6 bar, volume vessel 280 liter, hazardous fluids. location Europe so PED, cat1, result in minimum Module A.
I would like to go for EN13445 as code.
How can I design and manufacture this housings without the need of RT.

Any advice? or better to use other design codes?

 

Your purchase order will normally tie you down to one single Code. It sounds like your estimator missed a trick or did not read the PO. Fishing around for a 'cheaper' Code to 'skip' inspections sounds like a very suspect approach.

My advice is to follow all the rules - even when the fluids are not hazardous.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[XL83NL]

Eric, ironic_metallurgist has given you sound advice. I can add to that there's an escape in EN 13445 to reduce NDE, but the downside is your JE goes up; its called testing group 4. However, there are situations this group may not be used, so youd have to check to be sure.
Another possibility is, but Im not sure right now if thats for EN 13480 or EN 13445 (also), is to reduce RT, but I think that can only be done when you have SEP or art 4.3.

Also, whats the fluid you have? At which design temperature? Are you sure it's not considered a gas in the PED's context?

 

[MGZmechanical]

You can go to testing group 4 (factor 0,7 to material resistance) and see if it is enough with your design.

 

[r6155]

What is the cost of the human life?
Also do you want to avoid leak testing due to the cost impact?.

Regards
r6155

 

[XL83NL]

In it's essence, there's nothing wrong with the OP's question. He's not asking for a Code violation, but in fact implies to work acc Code.

You can go to testing group 4 (factor 0,7 to material resistance) and see if it is enough with your design.

No; see my previous, the OP needs to determine first if TG4 is acceptable for his application.

 

[kiad]

I agree with r6155. besides Decrease in joint efficiency will lead to increase in thickness and cost.

 

[Eric Wals]

thank you all, I agree never risk a life.
we manufacture 25 years pressure vessels. 95% all SEP, all pressure tested, 1.5x design pressure. Some vessels RT if customer or code ask for. Housings up to 3000psi design with a volume 200ltr, water under ASME VIII div1.
cross our fingers, but we never had problem, yes we had some small failures which came out during pressure test and PT.
This is just a general question as we find a way to manufacture high quality vessel against a competitive price. Just 6 bar fluid at ambient temp. feedback is appreciated.

 

[MGZmechanical]

In Europe for pressure vessel you have different test method and joint coefficients according the risk.
EN 13445-5 defines:
Level 4, no NDT required: z= 0,7. Just valid for non dangerous fluids, up to 20 bar, P·V=20000 over 100 C or P·V up to 50000 up to 100 C. T max 300 C and max thickness 16 mm, meterials groups 1.1 and 8.1.

Lebvel 3, 10% NDT for 1.1 and 8.1 up to 50 mm: z=0,85

If max pressure is 6 bar maybe you have big safety factors due to minimum thickness for, machining, welding distortion control,standard stock thicknesses... so you can go with 0,7 on the resistance.

Best regards,