Gas Lift Unloading Sequence & Mandrel Spacing Design

According to many industry experts, Gas Lift is the least understood artificial lift method, but its complexity is not the reason behind its misunderstanding. Instead, the challenge behind Gas Lift is that after implementing a lousy design, the well will often keep producing, unlike other artificial lift methods (e.g., ESP) that stop producing. Thus, operators fail to recognize design or operating errors that restrain production. Therefore, there is a significant potential to increase production by oil and gas professionals who understand the Gas Lift system and its fundamental and advanced principles.

The gas lift training ‘Gas Lift Unloading Sequence and Mandrel Spacing Design’ covers various topics like gas lift initial unloading, routine start-up of a gas lift well, and how to do a mandrel spacing design for optimal performance of the gas lift system.

This gas lift course starts by detailing the gas lift unloading sequence (evolution of tubing and casing pressure profile, CHP, WHP, and valve status during the gas lift well start-up) with IPO and PPO valves.

The course also provides an excellent platform for operators to gain in-depth knowledge of the challenge of integrity in gas lift wells. It will teach the best industry practices and existing solutions to mitigate the specific risks linked to gas lift.

Students will then be guided to make the gas lift mandrel spacing design of a well (number of gas lift mandrels required and at which depth each should be installed) without using any software. Hence, they will understand the fundamental principles of gas lift and know how to select their gas lift well design parameters properly (e.g., kick-off pressure). Advanced notions like the gas lift equilibrium curve, maximum rate estimation, and temperature models are explained clearly to give every student a high level of autonomy when dealing with gas lift design.

The last part of the training explains how to make such a mandrel spacing design using the nodal analysis software Prosper. Students will be guided within the “Gas Lift Design - NEW WELL” form in Prosper (meaning of each parameter to be filled and recommendations on best industry practice). Hence, with our ‘Gas Lift Unloading Sequence and Mandrel Spacing Design’ course, you will better grasp the different options available in Prosper to control your gas lift design.

This lesson is the 3rd of a series of 5 designed to help you reach an advanced level in gas lift oil production and operations. It follows the 2 courses ‘Forms of Gas Lift’ and ‘Gas Lift Equipment’ and precedes the courses ‘Gas Lift Optimization and Design with Existing Mandrels’, and ‘Gas Lift Troubleshooting’.

Objectives:

Participants will acquire a deep understanding of how the gas lift unloading sequence works. They will be able to connect all well parameters during that production phase. This is key knowledge for gas lift optimization and troubleshooting of any well. They will be explained the concept of gas lift mandrel spacing design through an exercise and will be coached so that they can perform such a design themselves manually or by using nodal analysis software to assist them (Prosper). The integrity in gas lift well will also be covered in detail.

Curriculum:

• Unloading the well basic principle
• Integrity in gas lift well
  
• Initial unloading following a drilling or a WO (how to empty your casing of the mud/brine without damaging your valves)
• Unloading sequence with IPO valves
• Unloading sequence with PPO valves
• Gas lift unloading principle explained by counting bubbles of gas
• Gas gradient formula and rule of thumb to quickly calculate your casing pressure at any depth
• Put it all together with an exercise (inflow/outflow/mandrel spacing design)
• Unloading sequence videos from suppliers
• Why installing a gas lift mandrel in a well portion where deviation is higher than 60°
• Gas lift system (fundamental principles, maximum rate estimation, equilibrium curve)
• Mandrel spacing design principles (where should you install your gas lift mandrels and how to do such design manually)
• Temperature models
• How to choose your kick of pressure
• Guidelines to make a mandrel spacing design with Prosper (how to fill the “GL design new” form in Prosper).

This course is designed for:

• Production, Petroleum or Well Performance Engineers to understand how the GL unloading sequence works and how to make a mandrel spacing design
• Field Production Personnel to understand how their GL well work and respond better to the questions of their support teams in town
• Completion Engineers to understand fully the needs for mandrels in a GL well.

Pre-requisites:

• Understanding of the well production mechanisms (inflow & outlfow)
• Knowledge of the existing forms of GL and GL equipment (especially GL valves)<
• Basic knowledge on well architecture
• Awareness on the oilfield terms.