Powder stabilization time and coating time limit

[nicholasktc]

Hi,

I am exploring the idea of automating HVOF coating in a mass production scale.

But currently, I have a few queries that I have not be able to sort out.

1. Powder stabilization time - how much time does it normally take for the powder feed rate to be stable upon "fire up", before it is good to start coating?

2. If were to do continuous spraying … is there a limit or guideline as to how long a gun is keep firing before it need to "rest".

Currently - most of the HVOF application that I have seen online, are batch processing .. would really appreciate is anyone can share with me, HVOF application in an automated setting.

Thank You
Nick

[Lemster68]

1. You never can really know unless you have a spraywatch or monitoring system to give feedback on when it is good spray and ready. You might have a leak or who knows what kind of problem so we prompt operator to confirm that it looks ok to start.

2. So long as your cooling is adequate you can run until there are spits from a dirty barrel or it wears so much that you develop leaks. Dirty barrel can vary depending on your spray parameters and feedstock material. Again, monitoring is necessary as to when to shut it down.