A multilateral well is a well with two or more laterals (horizontal, vertical, or deviated) drilled from a main mother well. This allows one well to produce from several reservoirs. Multilateral wells are suitable for complex geology where drilling more new wells to penetrate to those reservoirs is not economical.
How are multilateral wells drilled?
Multilateral drilling is a new technology developed after directional drilling, sidetrack, and horizontal drilling. The technology can increase oil-drainage area, improve oil well production, and greatly reduce reservoir development cost through drilling several lateral wells in one borehole.
Why multilateral wells are better than typical horizontal wells?
In general, multilateral wells perform better than single horizontal wells. The incremental production over single horizontal wells is in general greater than 70%. This advantage is because multilaterals provide greater reservoir contact in low-productivity reservoirs.
What is Multilateral well completion?
Multilateral completion systems allow the drilling and completion of multiple lateral boreholes within a single mainbore. This allows for alternative well-construction strategies for vertical, inclined, horizontal, and extended-reach wells. Multilaterals can be constructed in both new and existing oil and gas wells.
How is a horizontal well drilled?
Most horizontal wells are started by drilling a vertical well. After drilling down to the target rock, the pipe is pulled out of the well and a motor is attached to the drill bit. The motor is fuelled by a flow of drilling mud down the drill pipe, rotating the bit without rotating the entire pipe.
How much does horizontal drilling cost?
3.1 Construction Cost
| Service/Product | Price-Low | Price-High |
|---|---|---|
| Directional Boring – Rural | $6.00 | $7.00 |
| Directional Boring – Urban | $8.00 | $10.00 |
| Directional Boring – Rock | $42.50 | $271.00 |
| Conduit (2” HDPE) | $0.75 | $0.80 |
What are 4 types of wells?
Types of Wells
- Drilled wells. Drilled wells are constructed by either cable tool (percussion) or rotary-drilling machines.
- Driven wells. Driven wells are constructed by driving a small-diameter pipe into shallow water-bearing sand or gravel.
- Dug wells.
Why multilateral well construction and completions?
Multilateral well construction and completions reduce generated and embodied carbon during field development. Drilling rigs that are used to drill the boreholes represent sources of generated carbon of varying intensity based on their power source and consumption.
How do you prepare for a multilateral well bore project?
Prepare selective access and multiple kickoff points for current and future sidetracks and multilateral wellbores. Benefits of multilateral technology can be enormous. Field development plans define well counts required to drain the reservoir―often with significant technical constraints and uncertainty.
What is an ML well and what are its applications?
The most frequent applications of ML wells are in reservoirs that require sand control and in heavy oil reservoirs. In the case of sand control, the reason is often slot management on offshore platforms. More reservoir can be accessed from a single casing string to surface.
Why are laterals not used for injection wells?
Because most junctions do not contain pressure seals across the annulus, laterals are rarely good candidates for injection wells that operate at elevated pressures.
