Inch Diameter Calculation
How are inches of weld in piping counted?
The number of diametrical inches welded depends on the design and specifications of the piping system.
For example, a piping project typically involves the installation of pipe runs and fittings of different diameters, with each welded joint contributing to the count. It is necessary to consult the piping drawings, specifications or project documentation to determine the exact number.
Here is a typical case of how to count inches of weld using the picture in the book: "Estimator's Piping Man-hours Tool"
Number of Inches of Weld
Diameter Inch Calculation. The illustration above shows a discharge line starting at the discharge flange (2 1/2" diameter) of a centrifugal pump, then connecting through a 2 1/2" x 4" concentric reducer to a 4" diameter line terminating in an NPS 6" manifold.
To count the number of inches, count the welds according to the following table.
We notice that for the number of welds, we only consider the diameters of the components of the section we are considering. In the next entry we will analyze how the thickness (SCH), the tube materials and the external conditions affect the welding times for the same pipe diameter.