Cement evaluation tool: a new approach to cement evaluation

Journal Article · Sun Aug 01 04:00:00 EDT 1982 · J. Pet. Technol.; (United States)

DOI:https://doi.org/10.2118/10207-PA· OSTI ID:6111467

Froelich, B; Dumont, A; Pittman, D; Seeman, B

Cement bond logging achieves its greatest utility when it provides the production engineer with precise indications of cement strength and distribution around the casing. Zone isolation is of critical importance in production. Previous logging systems have yielded measures of cement bond that were circumferential averages of cement quality. These were difficult to interpret. Additionally, they were sensitive to the degree of shear coupling between pipe, cement, and formation and thus were affected by microannulus. The cement evaluation tool (CET) described here overcomes these difficulties. It provides a measurement of cement presence and strength, which is largely insensitive to microannulus. Its log output is interpreted easily. Tool design allows examination of the casing circumferentially at each depth. Impedance behind casing is measured. Laboratory calibration measurements allow this to be presented in terms of cement compressive strength. Cement channels are distinguished easily, and a zone isolation indicator can be presented. Additionally, casing internal diameter and distortion are displayed. European and North American field tests have been completed, and performance for a variety of well conditions is discussed. The ability of the tool to identify channels is confirmed. Sequential runs with and without excess pressure demonstrate immunity to microannulus in cases where CBL is affected but where microannulus is small enough to prohibit hydraulic communication. Geometrical measurements have been good indicators of casing deformation and have identified casing corrosion and wear.

• OSTI ID: 6111467
• Journal Information: J. Pet. Technol.; (United States), Journal Name: J. Pet. Technol.; (United States) Vol. 34:8; ISSN JPTJA
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
BUILDING MATERIALS
CEMENTS
COMPRESSION STRENGTH
DIMENSIONS
EVALUATION
FIELD TESTS
IMPEDANCE
MATERIALS
MECHANICAL PROPERTIES
PIPES
TESTING
THICKNESS
WEAR
WELL CASINGS