Flanged fittings with proximal, central, and distal sections between proximal and distal ends, the proximal section including a flange portion with bolt holes, and the central section including curved or angled surfaces, and which provide enhanced structural integrity and function for use in pipeline operations are described. The fittings can include an inner threaded surface capable of receiving a threaded plug to provide a primary seal in the fitting, and then can be capped with a finishing cap at the flange portion following a pipeline tapping process.