TLD-2500 Tube Leak Detector Test Guns
Pressure test heat exchanger tubes with air in 5 to 10 seconds per tube. A matched pair of guns, an air injection gun and a plugging gun, seals both ends so any pressure drop shows the leak. Tube IDs 0.28" to 1.23". Find your seal size ›
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- Complete kit, or replacement seals
- Tube IDs to be tested (choose 3 seal sizes)
- Seal material, if cleaning chemicals are a concern
- Quantity and date needed
| Specification | Details |
|---|---|
| Test Method | Air pressure decay, monitored on gauges at both guns |
| Tube IDs | 0.28" – 1.23" (7.1 – 31.3 mm; larger IDs, call us) |
| Air Supply | 40 – 125 psi (2.7 – 8.6 bar), 5 CFM minimum |
| Small Tubes | 0.28" – 0.48" ID: regulator required, 40 – 60 psi |
| Test Time | About 5 – 10 seconds per tube |
| Seal Stems | I: 0.28" – 0.48" • II: 0.49" – 0.83" • III: 0.84" – 1.23" |
| Seal Sizing | Seal and washer OD 0.02" – 0.06" smaller than tube ID |
| Seal Life | About 100 – 500 tubes per seal and washer set |
| Seal Materials | Rubber, elastomer, or inert seals available (match to tube cleaning chemicals) |
| Kit Includes | Air injection gun • Plugging gun • 3 seal sizes of your choice • Seal stems for all tube sizes • Carrying case |
What Is the TLD-2500?
A pair of air-powered test guns that pressure test one heat exchanger tube at a time. The air injection gun, with its air control and bleed valves, pressurizes the tube from one end. The plugging gun seals the other end automatically. If pressure holds, the tube is good. If it drops, the tube is leaking.
Leaking tubes cost you product, energy, and reliability, and can lead to contamination or equipment failure. The TLD-2500 finds them fast during preventive maintenance and turnarounds.
How to Test a Tube
Prep & Size
Clean the tubes of loose scale. Fit both guns with seals and washers sized for the tube ID, and connect air to the injection gun.
Seat the Guns
Insert the injection gun in one end and the plugging gun in the other. Press each washer firmly against the tube end and hold.
Pressurize
Hold the air control valve until the gauge is steady, then release. The valve closes automatically, isolating the tube under pressure.
Read the Gauges
Both operators watch their gauges. Falling pressure means a leak. Bleed off the pressure, mark any leaking tube, and move on.
What's in the Kit
Replace seals and washers on both guns at the same time. Seal stems swap out by tube ID range, and replacement seals can be made for any ID from 0.28" to 1.23".
TLD-2500 Seal Sizing Chart
Choose the seal kit whose range covers your tube ID. Seal and washer ODs run 0.02" to 0.06" under the tube ID. For tubes larger than 1.23" ID, call (800) 456-8721.
| Part Number | Tube ID Range | Seal OD | Washer OD | Comp. Tube |
|---|---|---|---|---|
| TLD-C-SK-0300 | 0.300" – 0.405" (7.6 – 10.3 mm) | 0.295" | 0.287" | 1 |
| TLD-C-SK-0375 | 0.375" – 0.475" (9.5 – 12.1 mm) | 0.354" | 0.346" | 1 |
| TLD-C-SK-0480 | 0.480" – 0.540" (12.2 – 13.7 mm) | 0.457" | 0.449" | 1 |
| TLD-C-SK-0445 | 0.445" – 0.515" (11.3 – 13.1 mm) | 0.425" | 0.417" | 2 |
| TLD-C-SK-0500 | 0.500" – 0.570" (12.7 – 14.5 mm) | 0.480" | 0.472" | 2 |
| TLD-C-SK-0563 | 0.563" – 0.630" (14.3 – 16.0 mm) | 0.543" | 0.535" | 2 |
| TLD-C-SK-0626 | 0.626" – 0.685" (15.9 – 17.4 mm) | 0.606" | 0.598" | 2 |
| TLD-C-SK-0670 | 0.670" – 0.735" (17.0 – 18.7 mm) | 0.649" | 0.642" | 2 |
| TLD-C-SK-0728 | 0.728" – 0.795" (18.5 – 20.2 mm) | 0.708" | 0.701" | 2 |
| TLD-C-SK-0795 | 0.795" – 0.845" (20.2 – 21.5 mm) | 0.775" | 0.768" | 2 |
| TLD-C-SK-0815 | 0.815" – 0.866" (20.7 – 22.0 mm) | 0.791" | 0.783" | 2 |
| TLD-C-SK-0690 | 0.690" – 0.755" (17.5 – 19.2 mm) | 0.669" | 0.611" | 3 |
| TLD-C-SK-0752 | 0.752" – 0.810" (19.1 – 20.6 mm) | 0.732" | 0.724" | 3 |
| TLD-C-SK-0874 | 0.874" – 0.935" (22.2 – 23.7 mm) | 0.854" | 0.846" | 3 |
| TLD-C-SK-0922 | 0.922" – 0.980" (23.4 – 24.9 mm) | 0.901" | 0.894" | 3 |
| TLD-C-SK-0937 | 0.937" – 1.001" (23.8 – 25.4 mm) | 0.917" | 0.909" | 3 |
| TLD-C-SK-1010 | 1.010" – 1.070" (25.7 – 27.2 mm) | 0.992" | 0.984" | 3 |
| TLD-C-SK-1065 | 1.065" – 1.120" (27.1 – 28.4 mm) | 1.055" | 1.047" | 3 |
| TLD-C-SK-1100 | 1.100" – 1.160" (27.9 – 29.5 mm) | 1.082" | 1.075" | 3 |
| TLD-C-SK-1160 | 1.160" – 1.206" (29.5 – 30.6 mm) | 1.149" | 1.142" | 3 |
Tube Leak Detector FAQ
How does the TLD-2500 find a leaking tube?
The plugging gun seals one end of the tube and the air injection gun pressurizes it from the other. Once the air valve closes, both operators watch their gauges. If pressure holds, the tube is good. If it drops, the tube is leaking.
What tube sizes can it test?
Tube IDs from 0.28" to 1.23" (7.1 to 31.3 mm), using three interchangeable seal stems. For larger tubes, call us.
What air supply does it need?
40 to 125 psi (2.7 to 8.6 bar) at 5 CFM minimum. For tube IDs from 0.28" to 0.48", attach the regulator and keep pressure between 40 and 60 psi.
How do I choose the right seal?
Pick the seal kit from the sizing chart whose range covers your tube ID. Seals and washers should be 0.02" to 0.06" smaller than the tube ID. Seals that are too small wear quickly and can stick or eject the gun.
How long do the seals last?
About 100 to 500 tubes per seal and washer set, depending on conditions and the operator. Replace them on both guns at the same time.
Should I use the TLD-2500 or the VLD-2500?
The TLD-2500 tests with air pressure using two guns, one at each end. The VLD-2500 Vacuum Leak Detector tests with vacuum from one end, with the far end plugged. Call us and we'll help you choose.
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