Multiple Quantities of the Same Vessel - Section VIII Div 1

[dalea60]

Normally we built pressure vessels per job. If the same vessel is required for another customer, we create new drawings, calcs and so forth even though it may be identical to an earlier vessel. Now we have a situation where we want to build a quantity of a particular pressure vessel for stock. As the inventory is used up, the shop would have to issue a work order to build more vessels to replenish stock. Is it possible to use the drawing, code calcs and so forth for the first units again as vessels are required (without effort by Engineering)? Sorry, this probably sounds like a stupid question to those of you that deal with building the same vessel over & over. I'd like to be able to use the same drawing & code calcs until a code addenda or edition change. Are there other things to consider? I'd have to come up with a different s/n method since we normally base the s/n on the job number. Usually our vessel drawing shows the NB number & s/n in a representation of the name plate but I can't very well do that in this situation.

Thanks for the help.

 

[gr2vessels]

The standard design documentation used for the fabrication of a type of vessel is acceptable and is commonly used in the industry;- refer to the standard air receivers, standard water heater tanks for domestic and industrial applications and many, many more examples. The design Code does not oppose the generation of standard documentation for "serial" produced, identical equipment. Obviously, the level of NDE has to be adjusted to the vessel "rating" and each vessel has to have it's basic "As Built" documentation, but items like WPS / PQR, PWHT and other similar procedures are used as pre-approved and need not be re-approved unless changed for good reason and are only referenced on a basic ITP document, attached to the equipment file. Then again, I have reviewed a similar Chinese ITP and to my astonishment, the same person signed for material reception, for welding, PWHT, painting and delivery preparation, but no AI certification of any kind ( I would expect the welding supervisor to sign for welding and the paint shop QA to sign for painting, etc...). It takes a bit of work to put together a reasonable standard documentation, but after that you'll be flying.
cheers,
gr2vessels

 

[dalea60]

I appreciate the help, gr2vessels.

Thanks