High-Pressure Sealing for Large-Diameter Pipelines: A 1500–2300 mm Custom Inflatable Pipe Plug for Water Tightness Testing

The Challenge

Water tightness testing on large-diameter pipelines—especially those above 1500 mm—faces two critical challenges. First, maintaining a stable seal across a wide diameter range. Second, withstanding high hydrostatic backpressure without blowout or leakage.

Standard inflatable pipe plugs typically operate at low inflation pressures of 0.3 to 0.8 bar and narrow diameter ranges, making them unsuitable for demanding large-diameter applications.

adial expansion, ensuring firm contact against the pipe wall even on rough or uneven concrete surfaces. It also delivers higher blowout resistance, preventing the plug from being pushed out by water backpressure exceeding 15 meters of test head. Perhaps most importantly, the plug maintains consistent sealing across the entire 1500–2300 mm range without pressure adjustment. As a result, one high-pressure plug can replace multiple lower-pressure units, significantly reducing inventory requirements.

Application in Water Tightness Testing

The 1500–2300 mm custom inflatable pipe plug is used in a straightforward sequence. First, the deflated plug is inserted at the test section boundary. Second, it is inflated to 2 bar using a suitable air compressor. Third, air pressure is monitored for stability to verify the seal. Fourth, the isolated pipe section is filled with water to the required test head. Fifth, water level or pressure is monitored over the specified period to check for leakage. Finally, the plug is deflated and removed for reuse.

Advantages Over Conventional Methods

Compared to conventional inflatable pipe plugs, which typically cover a narrow diameter range of around 200 mm and operate at 0.3 to 0.8 bar, this custom 1500–2300 mm plug covers a wide 800 mm span with 2 bar inflation pressure. While conventional plugs are limited to test heads below 8 meters, this custom plug can handle test heads exceeding 15 meters. Most significantly, where conventional methods would require four to five different plugs to cover the 1500–2300 mm range, this single plug does the job alone.

Conclusion

For large-diameter pipeline projects requiring reliable, high-pressure water tightness testing, a custom inflatable pipe plug with a 1500 to 2300 mm range and 2 bar inflation pressure offers a robust, efficient, and cost-effective solution. It combines wide diameter coverage with high sealing capability—essential for demanding field conditions.