Type V vs Type VII blast media on aircraft parts

[Hobbles]

Our plant repairs aircraft parts for the military. Regulations determine which type of media we can use on specific parts.

Recently our technicians have been complaining about the time required to strip paint using the softer type VII on some stubborn parts coated with primer.
They've shown me that type V works much better on other parts, stripping faster, but are concerned that the harder media might damage parts by propagating small cracks.

Also, the type V can be used at a lower pressure (20-30psi) than the type VII (30-45psi) and costs less, so I would like to be able to justify using it in more of our processes.

I've been asked to evaluate the repair process. Any suggestions on how to approach this?

Thanks in advance!

 

[SWComposites]

"Regulations determine which type of media we can use on specific parts."

seems like you need to talk to whomever is responsible for the regulations. you can't change the process without getting approval. presumably the regulator had valid reasons and data for selecting the approved methods

to justify a change, you will likely need to run trials with nominal process parameters and also the extremes of process parameters, then do detailed NDI, destructive and testing evaluations to verify that the revised process does not damage the material.

 

[Hobbles]

Yes you are absolutely right. I can't change the process without approval. There are channels I can follow to submit change requests, but need to justify it first.

We have NDI capabilities in-house, and it was my method of choice to begin with. I'm a newbie engineer, and wanted some reassurance.

Thanks!