The user-friendly resistance software, which is Microsoft Excel compatible, determines the total static pressure resistance for all of ABC Industries' Ducting.  This can be measured at sea level and altitude. You can customize your size selection report by date, customer and project.

To determine static pressure resistance, insert data into these input fields:  

(Blue typeface numbers are input fields. The red typeface numbers are calculated fields.)

CUBIC FEET/MIN (CFM) - consider a possible 10% maximum leakage loss as an add-on

LENGTH OF DUCT (FEET)

DIAMETER OF DUCT (INCHES)

# OF 90 DEG ELBOWS (TURNS)

# OF 45 DEG ELBOWS (TURNS)

K-FACTOR (FRICTION) - reference K-Factors* listed below

ENTRANCE LOSS - include for an added safety factor
EXIT LOSS - include for an added safety factor
ALTITUDE IN FEET - a zero equals sea level

To determine total pressure resistance (loss) for your system, add the velocity pressure fan resistance (loss), based upon the fan being used, to the static pressure resistance (loss) for your ducting specification; which was determined using the software.  Total pressure resistance (loss) must be within the performance curve of the selected fan, for the determined diameter of ducting, to achieve the desired performance.

*The K-Factors are as follows:

      MineVent® Blower Tubing (for Underground Mine) = 20

      MineVent® Blower Tubing (for Tunnels and Straight Taught Lines) = 15

      MineDuct® Wire Re-Enforced (Sewn Construction) = 60

      MineDuct® Wire Re-Enforced (Heat-Sealed Construction) = 35

      RigiDuct® Fiberglass Tubing, AutoFeed™ Cassettes, and Smooth Metal Duct = 13