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Improving volume control & influx detection for less experienced crews

Written by Snorre Lutnes | Feb 13, 2024

Deciphering Volume Control and Influx Detection

Volume control is fundamental in drilling and involves meticulously managing the balance between the amount of fluid entering the well and what's coming out. Think of it as maintaining the perfect equilibrium. When more fluid exits the well than enters, it's a red flag signaling an influx of formation fluids like oil, water, or gas. Conversely, when the well loses drilling mud, it can lead to a cascade of complications.

Challenges Faced by Inexperienced Crews

Volume control and influx detection may sound straightforward, but they are deceptively intricate. Experienced drilling crews can perform these tasks with ease due to years of hands-on experience and an in-depth understanding of drilling dynamics. However, for less experienced teams, several challenges stand in the way:

  1. Complex Flow Measurements: Achieving precise volume control requires measuring the flow of drilling fluids accurately. Inexperienced crews often rely on stroke counters and flow paddle indicators. Converting stroke counts into volume measurements involves pump efficiency calculations, which can be prone to errors.

  2. Volume Fluctuations: Monitoring the volume is a common practice, but it can be misleading. Drilling creates holes in the earth, which increases the volume of the hole. Additionally, drilling generates cuttings that mix with the mud and are carried to the surface. Furthermore, pit volume is affected by volume going in/out of the pit (flowline delay and mud caught all over the place), and pitch and roll effects.

  3. Tripping Pipe Complexity: Tripping pipe in and out of the well involves calculating the amount of displacement the pipe creates. This calculation requires considering factors like the size of the pipe and the bottom hole assembly. The largest error with tripping is X volume of steel in/out does not equal X volume of fluid in/out. There is a delaying factor which is why trip sheets are used. In deep wells with high pressure and temperature, factors such as mud compressibility and temperature-induced volume changes further complicate matters.

  4. Surface Factors and Rig Motion: Offshore drilling rigs often experience vessel motion, causing the mud in the pits to slosh around as the rig pitches and rolls. This motion affects the accuracy of pit volume monitoring and complicates the interpretation of pit sensor readings.

  5. Tripping Complications: When tripping pipe, crews must account for changes in volume due to the pipe's movement, which is further complicated in deep wells. The pressure factor, caused by the movement of the pipe up and down, can lead to surge and swab effects in the well.

These challenges make volume control and influx detection particularly daunting for inexperienced crews. Trendlines on pit volume and flow paddle readings become their guiding lights, but understanding the nuances of these indicators requires on-the-job experience regarding time to interpret and fluctuations of volume.

Read more: How to reduce workload for drilling personnel

Solutions for Enhanced Volume Control and Influx Detection

  1. Advanced Flow Measurement Technology

One solution to empower less experienced crews is the implementation of advanced flow measurement technologies. These technologies provide real-time, precise monitoring of fluid flow in and out of the well. By installing flow meters on the flowline, drilling teams can reduce their reliance on pit readings and flow paddle indicators. This technology offers a clearer, more accurate picture of what's happening downhole.

  1. Surface Back Pressure (SBP) Managed Pressure Drilling (MPD) Systems

SBP MPD systems create a closed-loop system which minimizes the influence of vessel motion. While these systems improve volume control, they often fall short in accurately monitoring the volume during non-circulating operations and are often off-line during tripping operations.

Introducing the EC-Monitor™: Your Solution for Efficient Drilling

The EC-Monitor™ addresses the challenges faced by less experienced drilling crews. It offers a comprehensive solution for volume control and influx detection. Here's how it works:

  • Elimination of External Effects: The EC-Monitor™ neutralizes the impact of rig and slip-joint motion, ensuring highly accurate return volume flow measurements. This means that even when the rig pitches and rolls, the system ensures highly precise return volume flow measurements. Inexperienced crews no longer need to worry about compensating for rig motion, making their jobs much simpler.

  • Inline Trip-Tank Design: Positioned above the telescopic joint, it absorbs volume fluctuations caused by motion, providing reliable measurements. This design feature simplifies volume control by reducing the impact of motion-related variations. Inexperienced crews can trust the system to provide consistent and accurate data.

  • Sensor Utilization and Compensation: Simple sensors measure return flow fluctuations, and the system compensates for these variations. It eliminates the need for crew members to manually adjust measurements, reducing the risk of errors.

  • Centrifugal Pump Integration: Ensures full lines in the system, eliminating vessel motion's influence and ensuring accurate measurements accurate, even in challenging offshore conditions.

  • Advanced Algorithms for Data Processing: Sophisticated algorithms filter out sensor noise and disturbances, which can be overwhelming for less experienced crews.

  • Continuous Volume Monitoring: Offers uninterrupted and accurate volume monitoring throughout all well stages, even during non-circulating operations. Unlike traditional methods that rely on intermittent measurements, the EC-Monitor™ offers uninterrupted and accurate comparisons between flow in and flow out and conducts volumetric measurement directly on the well when not circulating. This real-time monitoring significantly enhances the crew's ability to detect influxes or losses promptly, reducing the likelihood of drilling complications.

Read more: EC-Monitor™ wins best well integrity technology award

Takeaway: Efficiency and Reliability Unlocked

Enhancing volume control and influx detection is paramount for your drilling success, and it's achievable even with less experienced crews. Implementing advanced flow measurement technology and considering SBP MPD systems can significantly improve these processes.

However, for a comprehensive solution that simplifies monitoring and compensates for complex factors, offering a deterministic systemic and thus avoiding interpretation, the EC-Monitor™ can empower less experienced crews, and also ensure the safety and efficiency of your drilling operations.