Welding tube question

[ACEGOLFCARTGUY]

When welding both ends of a tube shut, should you have a vent hole drilled into it for pressure release? I've always wondered about this. It seems like if the tube is welded shut, pressure will build up inside from the heat and have no where to go. I doubt this would result in a big explosion but can it cause the weld puddle to blow out?

 

[fatboy99]

Ive Never Had Any Problem Welding End's On A Tube By Not Having A Vent Hole .You wont Build That Much Pressure Unless Your Filling It 1/2 Way With Water And Letting It Come In Contact With The Weld Area During Welding .
Brad

 

[FBJR]

Big or small tube, just seal it up. In fact a vent would allow rust to do its work faster!!

FB