CraftWEB Hot Glass Talk  

Go Back   CraftWEB Hot Glass Talk > Hot Glass > General Hot Glass Discussion

Reply
 
Thread Tools Display Modes
  #26  
Old 04-27-2017, 09:47 PM
Eben Horton Eben Horton is offline
Registered User
 
Join Date: Apr 2002
Location: Wakefield, RI
Posts: 3,928
Eben Horton is on a distinguished road
Quote:
Originally Posted by Franklin Sankar View Post
Eben if there is a space around the burner shouldn't it sucks air and keep the burner cooler??? If you put fiber it stops the air and what happens now?
Franklin
Actually after thinking about that for a while, the answer is that the furnace would want to use the gap of air space as a flue. A glory hole is open so the pressure is relieved through the opening in the door.
Reply With Quote
  #27  
Old 04-27-2017, 10:51 PM
Hugh Jenkins Hugh Jenkins is offline
Registered User
 
Join Date: Sep 2006
Location: Honoka'a, HI
Posts: 989
Hugh Jenkins is on a distinguished road
Glory holes are really an open vent hot chamber. The burner can act as a venturi and pull cool air. Furnaces are a more limited vent system that results in a positive pressure inside the fire box. The burner runs at such low internal pressure that it does not act so much as a venturi.

Some of the early sticktite burners that were blower pressured did create some draw in the burner block but this was easily overcome with better doors. It was not at all rare to see flame back around burner heads.

The above are very general and may not apply to the improvements we have made in furnace design.
__________________
Aloha, Hugh
Reply With Quote
  #28  
Old 04-28-2017, 10:24 AM
Tom Fuhrman Tom Fuhrman is offline
Registered User
 
Join Date: Apr 2002
Location: hills of Tennessee
Posts: 1,285
Tom Fuhrman is on a distinguished road
Dudley always suggested you use some fiber around his burners when installing them in furnaces.
Reply With Quote
  #29  
Old 04-28-2017, 10:30 AM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
The Old Gaffer
 
Join Date: Apr 2002
Location: Chocorua New Hampshire
Posts: 19,246
Pete VanderLaan is on a distinguished road
Quote:
Originally Posted by Tom Fuhrman View Post
Dudley always suggested you use some fiber around his burners when installing them in furnaces.
******
True but only at the very tip of the burner. He wants the body of it to be cold.
__________________
Where are we going and why am I in this basket?
Reply With Quote
  #30  
Old 04-30-2017, 08:00 AM
Eben Horton Eben Horton is offline
Registered User
 
Join Date: Apr 2002
Location: Wakefield, RI
Posts: 3,928
Eben Horton is on a distinguished road
Quote:
Originally Posted by Tom Fuhrman View Post
Dudley always suggested you use some fiber around his burners when installing them in furnaces.
Furnace yes. Glory hole no
Reply With Quote
  #31  
Old 04-30-2017, 08:35 PM
Franklin Sankar's Avatar
Franklin Sankar Franklin Sankar is offline
Registered User
 
Join Date: Apr 2002
Location: Trinidad, West Indies
Posts: 3,626
Franklin Sankar is on a distinguished road
This has always been a mystery to me. Getting nearer to the answer now.
When I close the door of the glory hole I do get some flames backing out of the gh burner port space. I then reduce the burner pressure. When the door is open I don't get flame out the burner space. That makes sense because it has a better path to get out i.e. The open door.
Franklin

Last edited by Franklin Sankar; 05-01-2017 at 06:07 AM. Reason: Changed propane to burner pressure
Reply With Quote
  #32  
Old 05-01-2017, 01:16 PM
Pete VanderLaan's Avatar
Pete VanderLaan Pete VanderLaan is offline
The Old Gaffer
 
Join Date: Apr 2002
Location: Chocorua New Hampshire
Posts: 19,246
Pete VanderLaan is on a distinguished road
Combustion of an air/gas mix expands at around a 25 to 1 ratio which helps explain all those explosions you see on television shows. It happens fast.

So, if you have a closed box with no vent and you have a burner lit, that mix is going to expand and needs somewhere to go. If the door is shut, it will try to come back out from whence it came. That in turn creates pressure on the burner and you have to try turning up the air gas pressure to overcome the back pressure. That uses excess fuel and wastes money plus not allowing the air fuel mix to really develop so you don't get the temps you want. Just about any furnace where the burner comes in from the side is going to operate more efficiently than one with a burner that comes in from the top. Putting a flue on it actually gets it hotter. It needs to be sized properly. Back in '76 at Pilchuck when I pulled the burners out of the tops of those old Toledo style furnaces, gas consumption dropped about 30%.
__________________
Where are we going and why am I in this basket?
Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 12:33 PM.


All published comments within these message boards are the opinions of its contributor and does not represent
the opinion(s) of the owner(s) of this website. Please see the Terms of Use file for more details.

Books to Help Artists Avoid Online Scams: Top 10 Email Scams | Social Media Scams

Powered by vBulletin® Version 3.7.2
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
CraftWEB.com. Opportunity Network. 2008. All Rights Reserved.