Hi,
We have some old operation sheets for glass peening which there are listed tolerances for air pressure and shot flow. Am I allowed to adjust these parameters in the program (within the defined tolerances) to meet the almen strips requirement? Is this in accordance to AMS2430?
The only AMS 2430 requirements for tolerances that I am aware of are 1) you must fall within the requirements of your customer, and 2) "3.10.2 intensity verification test strip measured arc heights shall be reproduced within +/-.0015 inch of the process parameter sheet and shall be within the intensity range for the part."
Your tolerances for your operation sheet air pressure and shot flow should be limited to maintain the proper intensity, and can be changed. I also recommend reading AMS2430 to verify that you are in compliance yourself.
Thank you Charlie.
So, if I understand you correctly you are saying that I can change the parameters to reach wanted intensity (within the customer requirements) if I have too low or too high intensity when verifying the test strips...?
Doesn't the change in parameters change the output of the shot peen operation?
Eg. if i experience too low strip verifications, i could raise the air pressure and lower the shot flow to reach the right arc height? But, doesn't this do something with the coverage of the actual part?
Any time you change a machine parameter, air pressure, media flow rate, change a hose or nozzle, you must run a new saturation curve (4-strips etc.).
If you submitted a plan to your customer indicating any/all of those parameters then you may need permission to continue. Usually the customer wants you to satisfy the intensity and coverage requirements and no mentin is made of parameters. But, if you submitted parameters then you would be expected to re-submit for customer approval.
Thank you for your answer Jack.
Will you be present at EI Shot Peening Seminar at Indianapolis this autumn?
I will attend and want to discuss this furthe than, if that's okey?
Example:
Process sheets state air pressure to be 40 with a tolerance
of +/- 5 you could adjust the setting anywhere from 40 to 50 without having to resubmit.
Ideally you should create your process by creating a tolerance box.
Create a saturation curve for the following parameters:
Air pressure low Shot flow low
Air pressure low Shot flow high
Air pressure high Shot flow low
Air pressure high Shot flow high
Yes, I will be presenting Tuesday and Wednesday at the workshop in Indianapolis as well as many others. I will be in the SAE meetings all day Thursday. Perhaps we can visit Monday night or Tuesday night?