Testing trunk pipelines

We use hydraulic (including stress) testing and pneumatic methods to test the reliability of pipelines.

The stress-test method is a modern technology for cyclical hydrotesting of gas pipelines during which test pressure is brought to 110 percent of the minimum specified pipe metal yield strength. Such load reveals the largest number of defects in a gas pipeline and removes elastic deformations, significantly improving the pipeline's operational reliability.

We use pneumatic methods of testing when it is impossible to apply hydrotesting to pipelines—when temperatures are below freezing and water is not available.

Working in various natural and climatic conditions has enabled us to develop proprietary all-season methods of pneumatic testing.

When applying all-season technology to test pipelines, we fill the test section of the pipeline with gas, which we draw from an active gas pipeline, and increase the pressure to its testing level using booster units. The flexible characteristics for gas compression that booster pump-compressor units possess ensure that we receive the necessary testing pressure as gas exits the unit. After testing is completed, gas is returned to the active pipeline. In this fashion, all-season technology permits us to reduce negative influence on the environment when compared with traditional technologies.