Page 80 - Estimators Piping Man Hour Manual
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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.
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