Introduction
Surge analysis plays a vital role in ensuring the mechanical integrity and operational safety of condensate transport pipelines, particularly during flushing operations and emergency shutdown scenarios. This study focused on evaluating transient pressure behavior in a condensate-based flushing system for a crude export pipeline, simulating pump trips and valve closures under varying operational states.
Key Observations
- Standards Applied: The surge evaluation was performed in accordance with ASME B31.3 (Process Piping) and ASME B31.4 (Pipeline Transportation Systems for Liquid Hydrocarbons).
- Simulation Tools: The PIPENET Vision Transient Module was used for steady-state and dynamic surge modeling, enabling accurate prediction of pressure fluctuations and flow behavior.
- Scenarios Modeled: Key events such as the sudden closure of ball valves and tripping of booster/export pumps were simulated.
- Equipment Analyzed: Simulations included pipelines, ball valves, emergency shutdown valves (ESVs), PLEM piping, and hoses rated to burst pressures.
Conclusion
Surge analysis for condensate pipeline flushing systems ensures safe and reliable pipeline operations under upset conditions. By adhering to ASME standards and using high-fidelity simulation tools, this analysis confirms pipeline adequacy without the need for costly surge protection hardware. The study reinforces the value of early surge modeling in optimizing pipeline design and operational strategies.
1. Surge Analysis for export pumping pipelines for transporting Condensate to coastal refineries from Bhogat to SPM for Vedanta,Rajasthan – Petrocil Engineers & Consultant
Introduction
A detailed surge analysis was conducted for a condensate-based flushing system designed to support a condensate export pipeline. The objective was to evaluate transient hydraulic conditions caused by rapid pump shutdowns and valve operations, ensuring pipeline safety and compliance with international design standards. The analysis focused on minimizing the risk of overpressure events during routine and emergency operations.
Methodology and Standards
The surge study followed a structured simulation approach using the PIPENET Transient Module, modeling both steady-state and dynamic conditions. The analysis adhered to the following standards:
- ASME B31.3 – Process Piping, applicable to on-plot process sections
- ASME B31.4 – Pipeline Transportation of Liquid Hydrocarbons, applicable to off-plot and transfer lines
- Transient pressure acceptance limit set at 110% of pipeline design pressure, as per industry best practice
Key Equipment and Pipeline Details
The analysis incorporated a range of components and flow paths across the condensate flushing system:
- Export Pumps (Booster and Mainline)
- Ball Valves
- Emergency Shutdown Valves (ESVs)
- PLEM Piping and 6” Marine Hoses
- 24”, 30”, and 36” Carbon Steel Pipelines, with varying elevation profiles
- Design pressure ratings evaluated against maximum surge values with burst ratings of connected hoses.
Key Observations
- Surge pressures in all simulated events remained within allowable limits; the maximum recorded surge pressure was well below the design burst capacity of the weakest connected component.
- No requirement for additional surge protection devices such as accumulators or rupture discs was identified.
- Simulation results validated the mechanical integrity of the system across all critical locations and scenarios, including pump trip and valve closure sequences.
- Transient flow behaviors confirmed that optimized pump shutdown procedures and valve timing were effective in mitigating surge risks.