UST Inspector Training Webinar

Subtitle

Line Tightness Testing

Line Tightness Testing

Tanknology TLD1 MethodConstant pressure line tightness testing is used by many testing vendors. The principles of the test are very similar from vendor to vendor. Tanknology’s TLD1 test method will be used to illustrate the general principles of a “constant pressure” line tightness test.

Line Tightness Testing

Tanknology TLD1 Method

•Connect test apparatus to the product line

•Add like product until visible in the calibrated site glass

•Apply constant pressure using a bottled inert gas (usually Nitrogen)

•Record site glass levels at uniform intervals

•Calculate leak rate

Line Tightness Testing

The portion of the line to be The portion of the line to be tested must be isolated from tested must be isolated from dispensers, submersible dispensers, submersible pumps or other associated pumps or other associated devices.devices.

••Check ValveCheck Valve

••Ball valveBall valve

••Isolation toolIsolation tool

Impact Impact ValvesValves

Calibrated Site GlassCalibrated Site Glass

Line Tightness Testing

ExampleExample

IFIF

1.1. 1 increment = .005 gallons1 increment = .005 gallons

2.2. We measure a 5 increment change in 10 We measure a 5 increment change in 10 minutesminutes

THENTHEN

1.1. .005 x 5 = .025 Gallon loss .005 x 5 = .025 Gallon loss (10 minute loss)(10 minute loss)

2.2. .025 x 6 = .15 .025 x 6 = .15 GPHGPH loss loss (Projected 60 minute loss)(Projected 60 minute loss)

Line Tightness Testing

• Level Drop may NOT equal a LeakDispenser Impact ValvesPacker “O” RingCrack STP headAir / Vapor trapped in lineProduct contraction

• Technician Training & Experience

• Proper Tools• Understanding Data Trends

Line Tightness Testing

Field Technician Data FormField Technician Data Form

Line Tightness Testing

Field Technician Data FormField Technician Data Form

Line Tightness Testing

Pass / Fail thresholdsPass / Fail thresholds

CFR 40 280.44 Methods of release detection for piping

(b) Line tightness testing. A periodic test of piping may be conducted only if it can detect a 0.1 gallon per hour leak rate at one and one-half times the operating pressure.

Manufacturer Thresholds may Manufacturer Thresholds may be more stringentbe more stringent

Steel +/Steel +/-- .01GPH.01GPH(10 x more stringent)(10 x more stringent)

Fiberglass & Flexible +/Fiberglass & Flexible +/-- .02 GPH.02 GPH(5 x more stringent)(5 x more stringent)

Suction Systems +/Suction Systems +/-- .025 GPH.025 GPH(4 x more stringent)(4 x more stringent)

Line Tightness Testing

Test Data Interpretation

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LeakTight

Line Tightness Testing

Line Tightness Testing