Login    Register
User Information
Username:
Password:
We are a free and open
community, all are welcome.
Click here to Register
Sponsored
Who is online

In total there are 63 users online :: 5 registered, 0 hidden and 58 guests


Most users ever online was 155 on Mon Aug 15, 2016 1:40 am

Registered users: Bing [Bot], Google [Bot], Majestic-12 [Bot], MSNbot Media, Yahoo [Bot] based on users active over the past 5 minutes

The Team
Administrators
Global Moderators
global_moderators.png CS

Using A Valve With A Larger Diameter Than The Barrel

A place to ask general spud cannon related questions.
Sponsored 
  • Author
    Message

Using A Valve With A Larger Diameter Than The Barrel

Unread postAuthor: n05gr0th » Wed Sep 10, 2014 8:27 am

Hey guys, I have a question for you.

What would the performance be like for a 3/4 QEV affixed to a 1/2 in barrel when compared to a 1/2 QEV for the same barrel diameter? What would the airflow be like with the larger valve feeding into a smaller barrel? Would it increase power, remain the same, or actually be detrimental to performance?

P.S. Anyone know if European style QEVs are available with NPT threads?

Many thanks!
  • 0

User avatar
n05gr0th
Specialist
Specialist
 
Posts: 42
Joined: Tue Aug 19, 2014 6:49 pm
Country: United Kingdom (uk)
Reputation: 1

Re: Using A Valve With A Larger Diameter Than The Barrel

Unread postAuthor: Technician1002 » Thu Sep 11, 2014 11:30 pm

In high flow situations, a small valve will have a pressure drop on it. This effectively lowers the pressure to the barrel. A larger valve will have a lower pressure drop resulting in higher pressure to the barrel. How much change between the valves, I don't know. In a larger valve with a small barrel, air velocity is reduced in the valve resulting in less shock waves in the valve and again less pressure loss.

Note that a 1/2 inch QEV does not have a 1/2 inch valve seat, so there is a considerable restriction to flow built in. A valve wide open does not have the same flow capacity of a piece of pipe the same size.

There is already a similar topic on this subject. http://www.spudfiles.com/pneumatic-cannons/topic25936.html
  • 0

User avatar
Technician1002
Chief of Staff
Chief of Staff
 
Posts: 5190
Joined: Sat Apr 04, 2009 11:10 am
Reputation: 14

Re: Using A Valve With A Larger Diameter Than The Barrel

Unread postAuthor: n05gr0th » Sat Sep 13, 2014 5:19 pm

I appreciate your response. Thanks for the link!
  • 0

User avatar
n05gr0th
Specialist
Specialist
 
Posts: 42
Joined: Tue Aug 19, 2014 6:49 pm
Country: United Kingdom (uk)
Reputation: 1

Return to General Spud Cannon Related

Who is online

Registered users: Bing [Bot], Google [Bot], Majestic-12 [Bot], MSNbot Media, Yahoo [Bot]

Reputation System ©'