Why are air pressure limits set on abrasives?

[robroy]

Hi!

Recently I've noticed that although my pressure sand blaster is rated at 125 PSI max safe pressure, the aluminum oxide abrasive I've been using says to blast at no more than 80 or 90 PSI.

Why are limits set on the pressure used with abrasives?

What happens that's so horrible if you blast at 125 PSI instead of 80-90? It sure works better at 125 PSI!

And the metal is thick enough that it's not as though the material + pressure is going to warp it.

Thank you!
Robroy

[71PA_Highboy]

Because at the higher pressure you shatter the media, and it turns to dust rather than be recycle-able.

If you are going for speed, use the pressure you want, but if you are trying to save/recycle your media, use the pressure recommended by the vendor.

hth,

Eric

[robroy]

Hey Eric, thanks! I wouldn't have ever guessed. That's very interesting!

Since I'm not re-using my media I'll just crank it up to 125 PSI.

Thanks again,
Robroy

[taylor351]

Higher pressure means higher temp also. Just be careful you don't warp the metal.

Keith