The Conduit Design Calculator automates the Mini-HDD calculations described in PPI TN-48 GUIDELINES FOR CHOOSING WALL THICKNESS FOR HDPE CONDUIT BASED ON “MINI-HDD” (HORIZONTAL DIRECTIONAL DRILLING): USING THE PPI CONDUIT DESIGN CALCULATOR
The Calculator uses input such as directional changes in the bore
path, and other project variables, to determine the Calculated Tensile
Load on the selected HDPE conduit, as compared to the allowable Safe
Pull Strength of the conduit in terms of Diameter Type (IPS, SIDR, or
True-Size), Wall Type (DR, SDR or Schedule), Diameter (nominal size),
and Material (type of HDPE).
Once the User enters the required Input data and clicks Calculate,
several outputs are shown simultaneously, along with a summary of the
User Inputs. Output can be emailed directly from the Calculator, or
printed as a PDF file or as a paper file.
The output of the Calculator can be used to assist the User in
selecting the most appropriate wall thickness of HDPE conduit to be used
for a specific application. A result shown in Green and with a Safety Factor
greater than 1.0 indicates that the displayed wall type will have
sufficient tensile strength to meet the required tensile forces, based
on the User Inputs and the embedded mathematical formulas and values.
In some situations, more than one wall type will have sufficient
tensile strength to meet the required tensile forces, and the User can
select the wall type based on those results and other factors.
For situations with burial depths or bore lengths beyond what the
Calculator allows, users are recommended to review PPI Handbook of PE Pipe - Chapter 12, PPI MAB-7 and/or ASTM
F1962 Standard Guide for Use of Maxi-Horizontal Directional
Drilling for Placement of Polyethylene Pipe or Conduit Under Obstacles,
Including River Crossings.