Back in Oman

January finds me again in Oman, one of my favorite places, and teaching, one of my favorite jobs.

Burney teaching gas lift

This time I'm sharing the load with Larry Peacock of AppSmiths Ventures.

Larry Peacock of AppSmiths Ventures, LLC

The weather was rainy when I first arrived.  Very unusual for rain to continue for several days in this country.  Finally the sun came out and Oman turned into the paradise that it normally is this time of year.

The coast of Muscat, Oman

Larry and I are teaching three classes on the basics of gas lift and how to use WinGLUE.  The participants are a mixture of Production Technologists (aka Production Engineers) and Production Programmers (similar to office-based Operations staff).  

Gas lift class in Oman

Although it has been about 9 years since I taught the course, it helps that I wrote the original course and was the technical advisor on the software development.  Larry reminded me of many things and I taught him some more secrets of gas lift.  Oh, and we are teaching 40 Omani's and expat staff how to do surveillance, analysis, design and optmization on gas lift wells.


This weekend I wrote a draft of a new gas lift test for the course.  Here are a few of the topics covered on the course and the test:


Gas Lift Competency

• Why gas lift is able to increase or sustain production
• What factors increase production into the wellbore through the completion zone
• How pressures in the tubing are influenced changes in produced fluid characteristics and mechanical changes to the well
• How the two primary methods of gas lift work and when to select each
• The three main gas lift objectives for gas lift, in order of importance
• The benefits and problems of gas lift
• The primary operational hazard that causes gas lift valves to fail prematurely and how to avoid this
• The relationships of pressure, volume and temperature on gasses and how to apply these relationships in gas lift analysis and design
• How the density of certain fluids change and how to estimate pressure at depth for various fluids
• How gas is most commonly measured and the most common reasons for poor measurement
• How to calculate the amount of gas that can go through a valve, what factors affect this rate, and how to size valves for a given gas throughput
• How to estimate the lift depth of a well from a flowing survey, from surface pressures, from valve mechanics and/or from valve throughput, 
• The effect of well surging on welltest and pressure survey measurements
• The four main causes of well surging and how to recognize and eliminate each
• The main types of gas lift valves, how each of these types work, how they are installed and retrieved, 
• The primary mechanisms by which gas lift valves fail over time
• The two main kinds of unloading gas lift valves and when to apply each
• How to select, set and size gas lift valves
• How to determine if a gas lift valve is open or closed using valve mechanics
• Two mechanisms for calculating the throughput of gas lift valves and the pros and cons of each
• The mechanisms by which gas lift wells unload and the primary causes of a gas lift string to fail to unload properly 
• How to determine to which depth a string of gas lift valves can unload
• How to space mandrels and the four criteria for a good mandrel spacing
• For a given injection rate, how to quickly determine the tubing pressure at any depth and the associated production rate.  How to use this technique in practice for gas lift design
• What is the surveillance process, why it is especially important for gas lift and tips on performing gas lift surveillance.

WinGLUE Competency

• How to enter a new well into WinGLUE with all the necessary well data in only a few minutes 
• How to determine the optimum amount of gas lift gas to a well and the operating envelope to avoid the four causes of gas lift well instability.  
• How to most efficiently review all the data entered into WinGLUE for a well
• Which models to use and how to calibrate a gas-lifted well tubing pressure model in WinGLUE using three main criteria 
• How various calibration parameters affect the well tubing pressure model
• How to calibrate the well inflow model
• How to perform gas lift well analysis in order to identify problems, estimate gains from improvements
• How to incorporate real-time surface data into a dynamic WinGLUE analysis
• How to redesign gas lift strings for current performance with an existing mandrel spacing for maximum performance and stability
• How to create and adjust a new mandrel spacing for the life of a completion
• How WellTracer works and how to use it improve surveillance and analysis in simple and very complex situations.  How to get WellTracer results even with unreliable data.
• How to use measured valve performance data to improve analysis in WinGLUE
• How to work efficiently with IPM GAP and get the benefits of full network modeling using WinGLUE
• How the Automatic Valve Tester can check gas lift valve quality and improve reliability of gas lift strings