Engineers Edge

Design and Engineering Forum

Engineering & Drafting Store | Engineering Data | Product Services Directory
Engineering Forum | Engineering Jobs | Engineering News
Engineering Calculators | GD&T Training ASME Y14.5M 1994

POSTING POLICY / RULES

Forum Moderators: randykimball, Administrator

Metal on Metal Valve Seal
Post Reply   Forum
Posted by: av7

07/17/2006, 10:56:18

Author Profile eMail author Edit

Im working on a senior project for an engineering class, and I'm trying to use a stainless steel ball in a metal seat for the seal. The valve flows air, but for durability I wanted to use the metal on metal seal. I can't get it to be air tight though. I've tried countersinking a cone shape and having the ball sit in the cone. I've tried hitting the ball with a hammer to get the indent of the sphere shape in the (softer) seat metal. I've tried 400 grit lapping compound. None of this has sealed it are tight. I'm getting a leak rate of almost .5 liters a minute or more. I know that metal on metal seals are used in carburetors and other common places, so it shouldn't be this hard should it? What am I doing wrong?







Post Reply | Tell a Friend (must be logged in) | Alert Admin About Post View All   | Next |

Replies to this message


Re: Metal on Metal Valve Seal
Re: Metal on Metal Valve Seal -- av7 Post Reply Top of thread Forum
Posted by: Kelly Bramble

07/17/2006, 22:26:20

Author Profile eMail author Edit

The ball surface variations are going to have to be matched to the seat surface to about a circularity of .003. Additionally, your going to require some static force (spring) to ensure the ball is seated against the seat. You might try some lapping compound like used on engine intake and exhaust valves to match the surfaces.







Post Reply | Tell a Friend (must be logged in) | Alert Admin About Post Where am I? Original Top of thread

Powered by Engineers Edge

© Copyright 2000 - 2019, by Engineers Edge, LLC All rights reserved.  Disclaimer