How To Weld A Pipe Flange. Generally it is used in small bore piping and only suitable for low pressure and temperature application. As the name suggests slip on flanges are placed on pipes by sliding them into place.
The connection with the pipe is done with 1 fillet weld at the outside of the flange. Sliding the slip-on flange onto the pipe. The X measure on the image are approximately.
The pipe schedule and the bore of the socket weld flange has to match so that there is no raised face there is no protrusion on the backside.
This is the most commonly used flange for pipeline. However I have not found solid reference for joining a fitting to greater wall thickness. Currently we recess the pipe about 18 to 14 in from the face of the flange and Tig weld the inside w 18 ER70s2. When welding a flange fitting or a piece of pipe together the gap spacing for welding them is established by the Welding Qualification.