Scientific Contributions Oil and Gas
Vol 48 No 3 (2025)

One Phase Well Design for Minimum Drilling Cost at ZAZ Field

Kharisma Idea (Faculty of Mineral Technology and Energy, Universitas Pembangunan Nasional Veteran Yogyakarta)
Yaumil Hasbiyallah (Faculty of Mineral Technology and Energy, Universitas Pembangunan Nasional Veteran Yogyakarta)
Kesuma Ardhana Oerika (Faculty of Mineral Technology and Energy, Universitas Pembangunan Nasional Veteran Yogyakarta)
Muhammad Yusrin (Faculty of Mineral Technology and Energy, Universitas Pembangunan Nasional Veteran Yogyakarta)



Article Info

Publish Date
29 Oct 2025

Abstract

Drilling cost components including rig, casing and accessories, well surface equipment, drilling mud, bits, cementing, and casing installation substantially influence the overall drilling cost. The One Phase Well (OPW) design is implemented by eliminating the surface casing, which is conventionally applied in casing designs for wells in the ZAZ Field. This study evaluates drilling parameters such as well data, well trajectory, pore pressure–fracture gradient, drilling time, material usage, and drilling costs. A well profile analysis is conducted to compare the Three Phase Well (TPW) and One Phase Well (OPW) designs. Analysis of drilling time, materials, and drilling costs is carried out to evaluate the cost reduction difference between the Three Phase Well (TPW) method and the One Phase Well (OPW) method.The OPW design reduces rig rental costs by 34.9%, bit costs by 53.9%, casing costs by 20.5%, wellhead costs by 8.7%, and mud costs by 3.7%. In contrast, cementing costs increase by 0.7%, and casing installation incurs an additional cost of USD 24,017. Overall, the total drilling cost difference between OPW and TPW amounts to USD 68,633, with OPW achieving a 12.7% reduction in overall drilling costs compared to TPW.

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Journal Info

Abbrev

SCOG

Publisher

Subject

Chemical Engineering, Chemistry & Bioengineering Energy

Description

The Scientific Contributions for Oil and Gas is the official journal of the Testing Center for Oil and Gas LEMIGAS for the dissemination of information on research activities, technology engineering development and laboratory testing in the oil and gas field. Manuscripts in English are accepted from ...