A “Bottleneck” is the part of the production system that causes the largest pressure loss and limits the flow rate of fluids from the reservoir to surface. Think of a pipeline system as a highway. A bottleneck is like a narrow bridge where traffic slows down, even if the rest of the road is wide and clear.
Key Characteristics of a Bottleneck:
- High pressure drop across a small segment
- Restricts the flow of oil, gas, or water
- Determines the system capacity: The entire production rate is limited by this weakest link.
Why Detect Bottlenecks?
- To optimize production (remove restrictions)
- To prioritize interventions (e.g., acidizing, recompletion, changing tubing)
- To reduce energy loss and improve flow efficiency
How to Locate the bottlenecks?
Locating bottlenecks is one of the most powerful uses of a well model. Here’s a clear, step-by-step method to diagnose where the pressure losses are concentrated, using your calibrated model in software like Pipesim or Prosper:
(1) Build a Fully Calibrated Well Model
Make sure your model matches actual well test data (Pwf, Q, gradient), uses the correct fluid properties and well configuration, and is segmented properly (wellbore, tubing, flowline, choke, separator).
(2) Review the Pressure Drop Profile (Segment by Segment)
Check pressure drop (ΔP) across each section:
- Reservoir → Bottomhole (Inflow)
- Tubing (hydrostatic + frictional + acceleration)
- Choke or Surface Equipment
| Section | Typical Bottleneck Indicators |
| Formation / Sandface | High Drawdown (Damage or low perm) |
| Tubing | Long section, small ID, high liquid holdup, wax or scale buildup |
| Choke | Sudden sharp drop across choke (≥30–40% total ΔP), sand accumulation |
| Surface Line | Long pipeline, scaling, high friction |
| Separator | Undersized, can’t handle high GOR |
(3) Use the Pressure Loss Distribution Plot
In Pipesim or Prosper, look for a pressure vs. depth or distance plot. These plots show where pressure loss is steepest. A flat section means low ΔP (not a bottleneck) and a steep drop = high ΔP → potential bottleneck.
