Reasons for using quality designed and manufactured Pipe Weld Purge Systems instead of Foam Dams
A very interesting quotation from one of our Weld Purging Best Practices Group members has been posted.
This raises additional reasons for not using foam.
Colin's comments are:
"Some pipe welding companies I've worked for buy in sheets of thick foam and the dams then have to be hand made (sometimes badly)."
"The rubber seal type always give a better seal and are more durable to heat." "Burning foam dams release fumes that are not healthy for a high purity weld or the welder. "
"More than once I've seen welders burn their hands whilst hurriedly removing a foam dam which had caught fire." "Masking tape used in their place can often start peeling off whilst the welder is oblivious "
"Foam dams can fall out during welding – a real sickener when you lift your hood to inspect your work. "
In addition to Colin's comments
- Foam is highly porous and will be full of voids containing air, water vapour and maybe even hydrocarbons that will outgas as the dams become warm from the welding process.
- There are return on investment charts available, showing how purging with modern products can save many thousands of dollars in gas costs on large stainless steel construction projects.