Traditionally, E&P companies employed vertical drilling practices. Simply stated, they would select a site, build a pad, and drill a single vertical well on that pad. Modern drilling technologies – directional or horizontal drilling – have changed this paradigm. Now E&P companies can select a single site, but build a larger pad to house multiple wells, drilling wells in various directions and depths to maximize the opportunities in that area. This practice provides advantages to an operator allowing them to maximize reservoir exposure while minimizing un-drained areas. The practice also introduces new complexities and efficiencies to the various functional disciplines involved along the well planning process:
- Surface and Mineral Land – Since drilling will branch out in multiple directions often the process of securing mineral rights is more difficult, as different wells may branch underneath the surface across property lines and into different formations with different ownership.
- Regulatory – Permits are issued for each well. When multiple wells are drilled on a single pad there are efficiencies in the preparation and submittal of permits. This also increases the likelihood that similar permits from the same pad will be approved in batch, which can expedite the approval process.
- Facilities & Construction – Significant efficiencies and cost savings can be obtained in the areas of construction and facilities when a single pad is shared to support multiple wells.
- Drilling & Rig Scheduling – Multi-well pads and batch drilling practices create both efficiencies and complexities in rig scheduling. For example, it is efficient and significantly reduces rig move time to bring a rig onto a pad and drill all the wells on that pad in sequence.
Conversely, multi-phased batch drilling creates added complexity in scheduling. Often horizontal drilling occurs in phases. First the rig will go around the pad and drill a surface hole for each well on the pad. Often the surface hole is drilled using a smaller rig, sometimes called a “Spudder” rig. Then another “Big Rig” will be moved on to the pad which will go around and drill to an intermediate depth, and then the rig will move around again and drill to production. Since different phases may be drilled by different rigs, and the order they move around the pad may change, the scheduling of rigs can get very complex.
How does WellCycle Well Planning support the batch drilling process?
Most traditional drill scheduling software supports the vertical drilling model with a single well pad. WellCycle Well Planning Version 2.0 is designed to support the complexities of multi-well pads and batch drilling. The system offers the versatility to apply the traditional model – one-pad one-well, or the new trend one-pad multiple wells. The system also supports the assignment and scheduling of different rigs to the different phases of horizontal drilling (surface, intermediate, production).
When scheduling rigs in complex batch drilling environments the potential exists for costly conflicts to creep into the rig schedule which may cause delays or even force a rig or completions crew to sit idle until the conflict is resolved. WellCycle helps E&P companies to identify these conflicts in advance and avoid costly delays. Some of the conflicts that are flagged by the WellCycle solution include:
- Another Rig on the Pad – If a Big Rig is brought to a pad while the Spudder rig is still on the pad.
- Well Clearance – If the Spudder rig is brought out before permits have been approved or pad construction has been completed.
- Stipulations – Many well sites have stipulations for environmental reasons. For example drilling might be delayed because drilling is prohibited during raptor mating season.
- Completions – If a Completions crew is sent out to complete a Well but the rig is still on the pad drilling other wells.
- Must Spud By dates – Many land leases have Must Spud By clauses where their rights expire if they don’t spud the Well by an agreed upon date.
WellCycle Well Planning manages all these complex variables, identifying potential conflicts, and coordinating activities to optimize the drill schedule and the entire well planning lifecycle.
Contact WellCycle for more information