How do you make well design decisions in drilling engineering?

2 Identify the well constraints

The next step in well design is to identify the well constraints, which are the factors that limit the options and performance of drilling a well. These may include the surface location, the subsurface geology, the drilling equipment, the operational costs, the regulatory requirements, and the uncertainty and variability of the data. The well constraints should be assessed and quantified, using reliable sources of information and appropriate tools and models. They should also be prioritized, based on their impact and likelihood of occurrence.

3 Evaluate the well risks

The third step in well design is to evaluate the well risks, which are the potential events or conditions that could adversely affect the objectives or constraints of drilling a well. These may include the formation pressure, the wellbore stability, the fluid loss, the gas kick, the stuck pipe, the blowout, and the environmental damage. The well risks should be identified and analyzed, using risk management techniques and best practices. They should also be mitigated, using preventive or corrective measures, such as well control, casing design, cementing, and contingency planning.

4 Select the well type

The fourth step in well design is to select the well type, which is the configuration and geometry of the wellbore. The well type determines the trajectory, the diameter, the depth, and the completion of the well. The well type should be chosen based on the well objectives, constraints, and risks, as well as the technical and economic feasibility of different options. Some common well types are vertical, directional, horizontal, multilateral, and extended reach wells.

5 Design the well components

The fifth step in well design is to design the well components, which are the elements that make up the well structure and function. The well components include the casing, the tubing, the drill string, the drill bit, the drilling fluid, the wellhead, the blowout preventer, the artificial lift, and the completion equipment. The well components should be designed based on the well type, as well as the mechanical, hydraulic, thermal, and chemical properties and interactions of the materials and fluids. The well components should also be optimized, using engineering calculations and simulations, to ensure the integrity, efficiency, and productivity of the well.

6 Review and revise the well design

The final step in well design is to review and revise the well design, which is the process of checking and improving the quality and validity of the well design. The well design should be reviewed by a multidisciplinary team of experts, who can provide feedback and suggestions on the technical and economic aspects of the well design. The well design should also be revised, based on the results of the review, as well as the changes in the well objectives, constraints, or risks, that may occur during the drilling operation. The well design should be documented and communicated, using standard formats and protocols, to ensure the clarity and consistency of the well design.

7 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?