venturi burner flame in burner tube

[Mungo Park]

I built a venturi burner and it works fine, I wanted to build another one for a friend and when I put it in the forge and have it running the flame is more in the burner tube than my other one. I can run my old one all day and the burner does not get hot. With the new one the heat creaps back towards the burner, any ideas of how to fix this.
Cheers Ron.

 

[DanGraves]

If the opening for the air intake is bigger that will help. Ventura burners suck air in and if it cant get enough it can cause it to creep up the tube or to much air. Play with the opening but I think it is because its not getting enough air.

 

[Stacy E. Apelt - Bladesmith]

Also, adjust your inlet pipe with the orifice. If it isn't in the sweet spot, it won't create the venturi. Raising the pressure helps sometimes.
Stacy

 

[Mungo Park]

Thank you both I will give it a try.
Cheers Ron.