Page 22 - Estimators Piping Man Hour Manual
P. 22

Section One-SHOP FABRICATION     5







     Minimum Bending Radii: Man hours shown for pipe bends are based upon a minimum bending radii of 5 nominal
         pipe size diameters, with the exception of large sizes and/or lighter walls which must be bent on longer radii.
         For bends having a radius of less than 5 diameters add 50% to man hours shown.

     Welding Long Bends: When it is  necessary to weld together  two or  more pieces of pipe to produce
        the  length required in the pipe bend, add the  man hours  for welding.

     Compound  Bends:  Man hours  of  pipe  bends  other  than  the  standard  types  illustrated or  with
        bends  in  more  than  one  plane  are  obtained  by adding together  the  man hours  of the  com-
        ponent bends that are  combined to produce the compound bend.

     Bends  Without  Tangents:  For  Pipe  Bends (Sch. 160 and less) ordered  without tangents, add 15%
        to  man hours shown.

     Bends With Long Arcs: For pipe bending with an arc exceeding 10 feet; add 100% to the bending man hours shown
         for each additional  10 feet of arc or part thereof.
     Connecting  Tangents:  No. 5  Offset  Bends  and  No. 7 U-Bends are  to be considered  as  such only
        when  the  bends  are  continuous  arcs  or  if  the tangent between arcs of the same  radius  is
        l'-0" long or less.  If  the  tangent  between arcs  is  longer  than l'-0", the bends should be
        considered as  compound bends, i. e., double angle bends,  double quarter  bends,  etc.

        No. 9  Expansion  U-Bends  are  to be considered  as  such only when  the bends  are  continuous
        arcs  or  if the tangents  between the  "U" and the 90° bends,  of the same radius are  I'-O" or
        less. When  such tangents  are  longer  than I'-O" the bends  should be man houred as  one "U"
        and  two 90° Pipe  Bends.  Bends  from  181°  to  359°  should be  man houred at  the same man
        hours as  a  No. 11 Bend.
     Offset  Bends:  No. 5  Offset  Bends  are  considered  as  such  only when  each angle  is  90° or  less
        and  the  connecting tangents between arcs  are  within  the  maximum  of I'-O" specified  in the
        preceding note.

     Beveled  Ends:  If  Pipe  Bends  are  to  have  the  ends beveled for  welding add the  man  hours  for
        beveling.

     Thread  Ends:  If Pipe  Bends are  to have the  ends threaded only, add the  man hours for threading.
     Flanged  Ends:  if  Pipe  Bends  are  to  have  the  ends  fitted  with  screwed  flanges,  slip-on weld
        flanges, welding neck flanges, or  lap joints  add the  man hours applicable  for  this  operation,

     Preparation  For Intermediate  Field  Welds:  When  Pipe  Bends, particularly  No. 9,10 or  11,  are
        too  bulky  for  transporting  or  handling  and  therefore,  must  be  furnished  in  two or  more
        sections  for  assembly  in the field, an  extra  charge  should  be  made for  the additional cuts
        and  bevels,

     Unlisted  Sizes:  For  unlisted sizes, use  the man hours of the next  larger  shown size.
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