iOS · Built for fuel technicians

DropTubeBuilder

Cut overfill-prevention drop tubes right the first time. Get exact upper, lower, and total tube lengths for OPW, Franklin Defender, and EMCO valves—plus tank charts and a searchable dispenser & ATG error-code library, all built for the field.

What it does

Practical tools for petroleum service work—no fluff, just the numbers you need on site.

🧮 Precise cut lengths

Enter your tank measurements and get exact upper, lower, and total drop tube lengths for OPW 71SO, Franklin Defender, and EMCO overfill valves.

Why it's accurate

Real 95% math

Shutoff is solved at 95% of tank volume—the way a horizontal tank actually fills—instead of a rough 95% of height. The OPW method matches the 71SO worksheet, and the geometry follows the Georgia EPD drop-tube approach.

📊 Tank volume charts

Build a calibration chart from tank diameter, length, and capacity in 1/8-inch increments to find the level you need.

🔎 Error-code library

Search dispenser and ATG codes for Gilbarco, Wayne, and Veeder-Root TLS-300/350/450/450 Plus/4i—with plain-English causes and troubleshooting.

📄 PDF reports & history

Export a clean calculation report to share or keep on file, and pull up past jobs from your saved history.

🌐 Six languages

English, Spanish, French, German, Hindi, and Chinese—so the whole crew can use it.

Service techs

Fuel-system technicians

Skip the scratch-paper geometry—measure, tap, and cut with the right numbers.

Installers

UST & forecourt installers

Set overfill valves where they belong, with a record you can export and keep.

Compliance-minded

Contractors & inspectors

Shutoff math grounded in the 95%-by-volume standard, not a height shortcut.

Field-ready on iPhone and iPad. Try it on your next drop tube job.

Download on the App Store