Peening production time. - Q & A Forum

Hi all.

I am looking to reduce peening time and are wondering what process variables I may change to achieve this?

Can a reduction in impingement angle reduce peening time to achieve 100% coverage?

Thx.

Reduction of impingement angle may reduce the peening coverage time but this might be a dangerous approach. The impact site may cause significant surface distortion leading to fracture nucleation.
Generally you would increase the media flow rate to reduce the coverage time. There are limits to this approach also.
Are you using air blast or wheel blast equipment? I need to know this to offer additional comments.

Thanks for the feedback. I'm using an air blast machine. Yes am very sceptical about doing this to reduce process time and aware of the risks. Just want to try and generate discussion.

Thanks

You can increase the media flow rate up to some limit. You will have to increase your air pressure as you increase media flow rate in order to maintain your intensity. Eventually the media flow rate will exceed the nozzle capacity (or air pressure available to maintain intensity). You could also consider using a larger diameter nozzle (and your compressed air consumption will go up dramatically). If you go to larger nozzle consider also going to larger blast hose.
Perhaps you can increase the number of nozzles.
Another was to increase coverage rate is to use smaller media (if allowed). You would maintain constant media flow rate pounds per minute but each pound of the smaller media has more particles (also known as dent makers...) and therefore your rate of coverage goes up quickly. Hope some of this helps. Let me know your progress.

Dear Sir,

Greeting form Amit Prajapati!

How much maximum and Minimum intensity we Measured on Almen Strip A?

How much maximum and Minimum intensity we Measured on Almen Strip C?

How much maximum and Minimum intensity we Measured on Almen Strip N?

I need your help to come out from penning intensity of shot penning machine.

help me in this issue sir,

According to SAE J442 and J443:
The "A" strip is used from 0.1 mm to 0.6mm
Less than 0.1 mm would use the "N" strip. No upper or lower limit is specified for the "N" strip.
More than 0.6 mm would use the "C" strip. No upper or lower limit is specified for the "C" strip.

thanks for your Feedback sir,

can we give 0.8 mm intensity on "A" strip?

or we have to go on other strip for 0.8 mm ?

can we know thickness of Almen Strip A , N,C?

help me in this issue sir,

For 0.8 mm intensity you should go to the "C" strip.
It's value is approximately 1/3 of the "A" strip so you should get just under 0.3 mm
Some shops may still wish to use the "A" strip for since it is just barely over the 0.6 mm recommended tolerance. If you must comply with SAE or other aerospace specifications then you don't have a choice. You would have to use the "C" strip.
Thickness of strips: A=0.051", N=0.032" and C=0.094".
Thickness of strips: A= (1.27-1.32 mm). N=(0.76-0.81 mm), C=(2.36-2.41 mm)

Please read J443 and J442 its a really easy to read spec for your questions about strips.

To answer the topic, do as Jack suggest. Increase the "dent makers".
I always start trying the highest possible shotflow. Some times you get a saturated strip with just one pass. Then you need to increase distance to part and maybe use a nozzle with wider spray.

I also suggest to look into your dwg requirements. If its old it might tell you to use 200% coverage. That is a major waste of time and is not good for the part beeing peened. Tell construction department to change to 100%.

Thanks for Valuable reply Sir ,

Mr.Jack Sir & Mr.BlomBerg (Sir)