ASME B16.14 pdf download Ferrous Pipe Plugs, Bushings, and Locknuts With Pipe Threads 3 PRESSURE–TEMPERATURE RATINGS (a) Pressure–temperature ratings for plugs and bush- ings shall be in accordance with ASME B16.4 if made of cast iron, or ASME B16.3 if made of malleable iron, ductile iron, or steel. Use of cored plugs or hexagon head bushings should be limited to...