Ball Seat Design

[Akamu]

There is a great debate where I work at about ball seat design and what is the most reliable configuration. Specifically, is it better to seal on the edge of the hole, or on the tapered portion of a cone (or "coined" feature) near the hole opening but not directly on it?

 

[unclesyd]

You are probably going to get many responses with as many recommendations. If you are talking about pumps and checks here a some suggestions

On balls less than 1/2" dia we usually formed the seat by diamond lapping the edge of the hole to conform to the ball.

On soft metal seats we used a harder ball and tapped it with a hammer and depending on the service lap the ball in.

On high pressure systems we tried to seat the balls on the edge of sharp hole. The hole had to have a very square edge.

We didn't seat very many on say a conical hole though we had some pumps that have this arrangment.

At one time we had some very high pressure pump valves that seated midway on 45° taper. The balls were about 1 1/4" in diameter.

The people that make replacement valves or parts have some good information on seats and balls and how to test them.

We tested our small valves with alcohol and the larger ones with a vacuum.