What are the procedures for preparing a metal fuel tank for welding?

The correct procedure for preparing a metal fuel tank for welding involves washing the interior with hot water and detergent, steaming it for thirty minutes, and then filling it with carbon dioxide (CO2). This method is crucial for ensuring safety during the welding process.

Washing the tank with hot water and detergent helps remove any residual fuel, dirt, or contaminants that may be present in the tank. The steaming process further cleanses the interior and displaces any remaining flammable vapors, significantly reducing the risk of explosion or fire when welding. Finally, filling the tank with CO2 serves to create an inert atmosphere that prevents combustion while welding, as CO2 is non-flammable. This step is vital for ensuring the safety of the welder and integrity of the work being performed.

In contrast, other options could pose significant safety risks. For instance, filling the tank with water and sealing it tightly may not effectively eliminate all flammable vapors, as water cannot fully displace air trapped within the tank. Filling the tank with gasoline is extremely dangerous, as it introduces highly flammable material directly into the welding environment. Removing all paint and letting the tank dry completely is necessary for creating a suitable surface for welding, but it does not address the critical issue of eliminating