What is the Difference between a Ball, Toggle, and Plug Valve?

Lately we (technical service) have had multiple calls asking the question “What is the difference between a ball, toggle, and plug valve?”   The first call I took actually caught me off guard because this has not been a common question.  My answer went something like this: “For two-handed operation, I prefer the ball valve, and for single-handled operation, like when you need to reach behind a piece of equipment, I prefer the toggle valve." Then I was asked about the plug valve, and I said I'd never used one (that I remembered).

I didn’t give this brief conversation a second thought until this same customer contacted their Restek sales representative and asked the same question because they said I did not provide them a sufficient answer. Lesson learned; I realized I needed a better answer than simply sharing my experiences with a customer.

I had an idea of how the ball and toggle valves worked but not the plug valve, so I tried to find some literature explaining the differences. I didn’t find what I was looking for, but Swagelok had some very useful descriptions and drawings in their catalogs, so I decided to write this post and include the links below for those of you who may have the same question or those of you who may already have a favorite valve, but do not know the details of how they work.

Toggle:  http://www.swagelok.com/downloads/webcatalogs/en/MS-01-54.pdf

Ball:       http://www.swagelok.com/downloads/webcatalogs/en/ms-02-331.pdf

Plug:     http://www.swagelok.com/downloads/webcatalogs/en/MS-01-59.pdf 

 

The valves that Restek offers can be found here.  Valves (restek.com) 

Toggle Valve Swagelok Shut-Off Gas Valve