High Pressure High Temperature (HPHT) Well Design

• Main Author: Mohd Sukri, Eskandar
• Format: Final Year Project
• Language: English
• Published: Universiti Teknologi Petronas 2013
• Subjects: T Technology (General)
• Online Access: http://utpedia.utp.edu.my/10704/1/Dissertation%20%28Final%29.pdf; http://utpedia.utp.edu.my/10704/
• Institution: Universiti Teknologi Petronas

The depletion of existing fields & scarcity of easier reservoir targets in Malaysia have forced the National Oil Company (NOC) to explore new plays such as deepwater drilling, high pressure high temperature (HPHT) drilling & reopen onshore exploration block in Malaysia. These strategies have proven to be successful especially by recent onshore discovery after 24 years by an international operator. However, it must be emphasised that the operator is unable to drill to deeper HPHT sand pays that may have high hydrocarbon quantity due to limitations associated with HPHT conditions such as: • Narrow drilling window margin between pore & fracture pressures • Reduced kick tolerance • Higher probability of operational problems such as lost circulation, stuck pipe & well control issue Due to these limitations, HPHT wells often have higher non-productive time (NPT) committed in resolving operational problems particularly lost circulation & well control issue in narrow drilling window margin compared to conventional wells that result in higher economic risk. Thus, there is a requirement to have proper HPHT well planning & design to maximize safety, eliminate NPT & increase efficiency. This paper presents the approach in planning & designing optimum onshore HPHT well design using well design package software based on real field data. Within this approach, a refined kick tolerance calculation used in casing shoe setting depth selection is introduced by incorporating the effect of temperature which is dominant in HPHT well. In addition to that, this paper also presents the optimization of casing design & wellbore hydraulics that complies with NOC drilling standards to ensure that this well is able to reach its objective target depth safely & fulfil all of its objectives. It must be noted that this paper is limited to elements present in typical Basis of Well Design (BOWD).