China
Africa
Explore chapters and articles related to this topic
Impact of the Changes on the IOC-OSC Relationship
Published in Basak Beyazay-Odemis, The Nature of the Firm in the Oil Industry, 2015
As is usually the case on oil fields, several companies were involved in the Macondo well. BP Exploration & Production Inc. was the lease operator of Mississippi Canyon Block 252, which contains the Macondo well. The Macondo prospect is owned jointly by BP (65%), Anadarko Petroleum Corporation (25%) and MOE Offshore, a unit of Mitsui (10%). The rig, namely Deepwater Horizon, is a semi-submersible drilling unit owned and operated by Transocean under contract to BP. Cementing and mud logging services for the well were provided by Halliburton and the drilling fluid was supplied by MI Swaco (a unit of Schlumberger). BOP was manufactured by Cameron and the float collar by Weatherford International. In addition, Schlumberger performed wireline services but left the rig on the day of the accident. Schlumberger was also contracted to do a cement bond log test but BP decided to skip the test. BP as the operator was responsible for the integration of different services and final decisions related to these services, to wit BP defined the drilling programme, designed the drilling unit and chose the type of BOP to be used. As is usually the case on the platform, the decisions were taken by BP but executed by service companies such as Transocean and Halliburton.
Production Well Design, Construction, and Maintenance
Published in Thomas M. Missimer, Ian C. Watson, Water Supply Development for Membrane Water Treatment Facilities, 1994
Thomas M. Missimer, Ian C. Watson
Many wells constructed to feed membrane treatment plants are deep and have a rather complex design. When working in the subsurface, many things can go wrong resulting in either minor or major defects in the well, such as partial joint separation, cracks in the casing, holes in the casing, or defective grouting at the base of the casing. Since most water wells carry only a 1-year warranty, it is necessary to carefully inspect the final constructed well. Some degree of inspection can be obtained by running a caliper log, a cement bond log, or various other geophysical logs to assess major defects. However, the most detailed inspection can be obtained by running a downhole camera survey of the well in either black and white or color. The videotape can be carefully reviewed for defects, and it can be stored for future comparison if the yield of the well changes (see Chapter 13). The cost of a downhole camera survey is quite reasonable, especially if several wells are surveyed at the end of a construction contract. A chemical analysis should be obtained on the water to analyze for any substances not compatible with the membranes. The silt density index should also be measured before placing the well in service.
Cement-casing shear bond strength: a review of the affecting variables and various enhancement techniques
Published in Petroleum Science and Technology, 2023
Sivakumar Pandian, Gaurav Hazarika, Udita Deota, Divya Shah, Rakesh Kumar Vij
The integrity of the cement sheath is evaluated using a sonic tool (cement bond log/variable density log) which gives an exact picture of the cement-casing and cement-formation bonding (Shook, Frisch, and Lewis 2008). A variable density log could predict the precise location of partial bonding and channeling. 2D and 3D computed tomography scanning has also been used to study the bonding between cement-casing and cement-formation (Andrade et al. 2014). The digital image correlation technique is also a novel technique to oversee strain development over the cemented casing surface when it experiences a diametric compression (Nath et al. 2018). The temperature and noise logs are also occasionally used to detect leaks or flow behind the casing (Hartog, Davies, and Stewart 1983). Either of these methods may be used individually or in combination based on the complexity of the oil wells. Numerical simulations and modeling can also be used for simulating the shear-bond strength between cement and casing. Similarly, Lamik et al. (2021) developed a two-test cells procedure to detect the shear strength of the casing-cement and cement-rock interfaces under quasi-static and dynamic axial load. Based on these test results, 3D modeling attempts can be made to predict the lifetime of the cement-bond.