Page 52 - Industrial Process Plant Construction Estimating and Man Hour Analysis

Chapter 2

Process piping

2.1 Section introduction—Piping schedules and tables
This section contains schedules and tables that cover the complete labor for the
field fabrication and installation of process piping in an industrial facility. The
direct craft man-hours for handling, welding, and bolting pipe are based on
welding methods, pipe wall thickness, pressure, and temperature. The piping
schedules for large bore pipe units for handling pipe are in diameter inch-feet,
and the units for welding, bolting, and handling valves are in diameter inches.
Piping man-hour tables, for carbon steel piping, are derived from the schedules.
The actual man-hour production units were developed from job cost reports for
process piping installed in the field on construction projects. The projects
involved large crew sizes, a low ratio of regular employees, and a safe work-
place that strives for zero accidents. Each of these factors has a negative effect
on productivity and has been considered in the development of the piping man-
hours. Standardized man-hours are required so that all work is from the same
“baseline” data. The baseline can be modified, and the standard man-hours
can be set up in a computerized estimating system. Man-hours are for direct
craft labor and do not include craft supervision and indirect craft support
man-hours. Refer to Schedule D—alloy and nonferrous weld factors to apply
the percentages for field fabrication and erection of alloy and nonferrous piping.

2.2 Piping section general notes

Handling and erecting pipe—man-hours to unload, store in lay down, haul, rig,
and align in place.
Field handling valves—man-hours to place screwed, flanged, and weld end
valves and expansion joints.
Field handling control valves and specialty items—man-hours are two times
manual valves per valve.
Field erection bolt ups—man-hours per joint to bolt-up valves, expansion
joints, flanged fittings, and spools.
Making on screwed fittings and valves—man-hours for cutting, threading,
handling, and erection per connection.

Industrial Process Plant Construction Estimating and Man-Hour Analysis.
https://doi.org/10.1016/B978-0-12-818648-0.00002-8
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