Safety First! Can Pipeline Hydraulic Modeling Lower Your Project Risk?

Posted by Matthew Stanton on Wednesday, August 30, 2023

Think about replacing an aging pipeline in your system. The current pipe is 4” and you don’t know what size to use as a replacement. Will the area see an increase in flow due to new development, or are there closures that will cause a decrease in future flow?

What if a service technician wants to shut down a pipeline to repair a regulator or valve? Do you know what the effects would be on the system with this pipeline section out?

What is Hydraulic Modeling?

A Hydraulic Model is a computer-based representation of a pipeline system. It mimics the assets in the field including pipe, valves, regulators, and compressors. A model can be as simple as stick drawings or built using mapping data. The software uses multiple equations to quickly determine calculations across the system and “solves” for a variety of parameters including pressures, flows, temperatures, and gas composition. Models can be run as a steady-state simulation or a time-based transient simulation, and can be used for upstream, midstream, transmission, and distribution systems.

Why is Hydraulic Modeling important?

While it doesn’t control the actual system in the field, it is a very powerful tool engineers can use for various analyses, such as the sizing of pipes and facilities, value closure consequences, determination of the impact of large volume draws, and many other applications. The model provides a simulation tool which allows for changes to be vetted and tested before they are implemented in the field, which results in reduced time and expense and the safer operation of your system.

Real-world applications of Hydraulic Modeling:

Hydraulic Modeling can be useful for many scenarios including but not limited to:

Locating leaks or pipeline blockages Effects of pipeline isolation or valve closures Facility sizing and utilization Pressure uprating or derating Customer outage potential Daily operations and optimization Risk modeling Capacity analysis and system expansion potential

How Hydraulic Modeling Could Affect Your Community:

In September 2018 in Merrimack Valley, Massachusetts, distribution lines were over-pressured and caused a series of fires and explosions, killing or injuring several residents. Low-pressure distribution lines were fed by larger, higher-pressure lines through a series of regulators. As some of the low-pressure lines were replaced, workers did not remove the regulator sensors on the old pipe and install them on the new pipe. This caused the regulators to read zero pressure as the old pipe was shut off and evacuated. The regulators opened to full capacity and fed high-pressure gas to the entire downstream system and the connected residences.

The NTSB determined weak engineering management and an absence of adequate planning, review, and project oversight to be the probable cause. The secondary cause identified was that the system did not have necessary overpressure protection. Since the incident, the NTSB, PHMSA, state, and other federal regulators have adopted new regulations regarding the planning and engineering of gas systems. These regulations draw attention to the importance of hydraulic modeling in the planning, engineering, and work procedures involved in the replacement of pipelines and facilities.

Safety is our top priority, and we know it is yours too! If you think your project can benefit from Hydraulic Modeling, please contact me. Our team of experts are excited to help you use hydraulic modeling to lower project risk, time, and cost.

Categories: Oil & Gas Infrastructure

Tagged: Pipelines  |  Natural Gas  |  Health & Safety