I.P-2 ERH737-6007A16 Tolerance Table.pdf

This document is a fabrication tolerances specification table for welded/fabricated assemblies and machining/general work. The specification establishes dimensional tolerances across three categories: casting, machining/general, and weldment/fabrication operations.

For casting operations, tolerances range from ±0.06 to ±0.26 inches depending on the dimension range, with smaller tolerances applied to smaller dimensions (0.0 to 2.0 inches at ±0.06/-0.06) and larger tolerances for bigger dimensions (15.0 inches at ±0.26/-0.26). Machining/general tolerances are significantly tighter, ranging from ±0.1 inches for dimensions 0.00 to 6.00 inches down to ±0.005 inches for dimensions 18.00 to 38.00 inches, with three precision levels (1PL, 2PL, 3PL) specified. Deck thickness tolerances are set at ±0.2 inches. Fillets and radii specifications range from 0.06 to 0.26 inches. Angular tolerances are defined at ±1° for piping and ventilation ducting, ±0.5° for angle between hanger mounts (with a 60° minimum to 120° maximum constraint), and ±0.5° for all other applications. Additional specifications reference ANSI Y14.36-1978 for surface texture symbols and FED-STD-H28 for thread specifications.