ダクトサイズ一括選定 Pro

Are you manually entering airflow values ​​for each duct to determine its size?

This app is a tool that instantly and automatically selects the size and thickness of low-pressure galvanized steel ducts used in HVAC and ventilation systems based on airflow values. You can paste the airflow values ​​for all selection points together for batch selection, and it works completely offline on-site.

■ For those who:
・Are just starting out in equipment design and lack confidence in duct size selection
・Spend time and effort reading duct measuring tapes
・Feel hesitant to ask senior colleagues if their selected sizes are correct
・Want to process multiple selection points at once to save time on drawing creation

■ Main Features
・Automatically selects round and square duct sizes simply by entering airflow values
・Displays candidates in order of least material (smallest circumference). Choose from economical options
• Automatic plate thickness determination (compliant with the Standard Specifications for Public Building Construction)
• Input and calculate multiple airflow rates at once (copy and paste from Excel, etc.)
• Copy selected size with one tap
• Freely set the criteria for unit pressure loss (Pa/m), wind speed, and aspect ratio
• Operates completely offline (no communication required, data only on the device)
• Save and recall for each project
• Can also be used to "check your answers" for sizes you've selected. It's like having a senior colleague by your side to check your work anytime.

■ About the Developer
30 years of experience in designing air conditioning and sanitary equipment (Building Equipment Engineer/Fire Protection Equipment Engineer Class A Category 1/Second-Class Boiler Engineer). Developed this software to reduce the "work burden" of duct selection, which was a struggle for me as a newcomer, and has made nearly 300 improvements, prioritizing ease of use and readability.

■ Calculation Basis
• Duct size: Selected using the "isobaric method," which is standard in air conditioning design. Calculation results have been verified by comparing them with the friction loss diagram in the Ministry of Land, Infrastructure, Transport and Tourism's "Building Equipment Design Standards."
* Rectangular ducts: Calculated by converting to an "equivalent diameter" that results in the same pressure loss as a circular duct.
* Plate thickness: Complies with the Standard Specifications for Public Building Construction, Mechanical Equipment Construction (2025 edition).

■ Caution
* This assumes galvanized steel ducts for low-pressure, general air conditioning. Smoke exhaust, high-pressure, kitchen ducts, etc., are not covered.
* This application is a design aid tool. Final verification should be done by the designer themselves.