Insights from David Soyster, PE, Mechanical Engineering Chief
Pipeline systems are designed for specific operating conditions, but according to David Soyster, PE, many long-term performance issues begin when systems evolve beyond those original assumptions.
As flow demands change over time, pumps, valves, and other equipment are often pushed outside their preferred operating ranges, creating reliability, maintenance, and efficiency concerns that may not have existed when the system was first designed.
When System Conditions Change
One of the most common issues David encounters is increased pipeline throughput due to changing market conditions or operational demands.
While the original design itself may still be sound, operating at higher flow rates can force pumps to run outside their preferred range and increase fluid velocity throughout the system. Over time, this can lead to additional wear, maintenance concerns, and reduced reliability.
Low-flow conditions can create similar issues. When pumps consistently operate below their intended range, performance and equipment longevity can also suffer.
To address these challenges, engineering teams may evaluate solutions such as Variable Frequency Drives (VFDs), pump de-staging, or equipment replacement. However, David emphasizes that an accurate hydraulic model is critical before determining the appropriate corrective action.
Using SPS for Surge Analysis & System Modeling
David highlights SPS (Synergy Pipeline Simulator) as a valuable tool for transient and surge analysis within pipeline systems.
“A surge event is caused by an unexpected condition, such as a valve closure or a pump trip,” David explains.
Using SPS, engineering teams can model pipeline geometry, valve characteristics, pump curves, elevation profiles, and fluid properties to simulate how the system responds during upset conditions. The model is then calibrated using SCADA data to reflect real operating behavior.
This process allows engineers to evaluate potential surge scenarios and develop mitigation strategies that help keep system pressures within allowable limits.
While surge events are not planned for, properly modeled systems help operators understand how the infrastructure will respond if one occurs.
Designing Within Real-World Constraints
On projects like Colonial Dulles Airport, David notes that engineering challenges often extend beyond hydraulics alone.
For the project, one of the primary constraints was limited physical space. The objective was to install a utility tank capable of receiving potentially contaminated product from pigging operations while still maintaining access to existing infrastructure.
The project team worked closely with operations personnel to determine volume requirements, optimize tank sizing, and ensure the system maintained operational flexibility for future maintenance activities.
David emphasizes that collaboration across engineering disciplines and operations teams was critical to achieving the best possible design within the project constraints.
Misconceptions That Create Operational Problems
One misconception David frequently encounters is the idea that “bigger is better” when sizing equipment such as control valves, meters, and pumps.
In reality, oversized equipment often creates operational inefficiencies later in a project lifecycle.
Oversized control valves may operate nearly closed during normal conditions, reducing controllability. Flow meters operating outside their preferred range can lose accuracy and reliability. Oversized pumps may require throttling valves to reduce pressure, wasting energy and increasing maintenance demands.
Proper equipment sizing is not simply about maximum capacity. It is about understanding how the system will actually operate over time and ensuring equipment performs within its intended range.
Need support with pipeline systems, hydraulic modeling, or mechanical engineering services? Contact AED Energy Services (AEDES) to discuss your project and learn how our team helps optimize long-term system performance.
