Page 80 - Estimator's Piping Man-Hour Manual 5E
P. 80
Section One-SHOP FABRICATION 63
FULL FURNACE STRESS RELIEVING AND
HEATING TREATMENT
Carbon Steel and Alloy Materials
NET MAN HOURS
Fahrenheit Temperature Per Hundred Pounds
0° to 1250° Inclusive 0,3
1251° to 1400° Inclusive 0.4
1401° to 1700° Inclusive 0,7
1701° to 2200° Inclusive 1.1
Exposed sections of pieces too large to be placed entirely within the furnace will be included in
subsequent furnace heat or heats until all parts of the piece have been stress relieved or heat
treated. To calculate the man hours for this operation use: total weight of fabricated piece times
man hours per pound depending on temperature, times total number of times piece must be heated
to get full coverage.
Quenching is included in the above man hours. Materials to be quenched after annealing must
not exceed over-all furnace dimension.
