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Cement optimisation
Introduction
Engineering and Cementing Design Practices
Normal design practices involve the preparation of a draft cementing programme by the
Onshore cementing engineering personnel, once the finalised drilling programme is
available.
A typical cementing programme would include:
·  recommended slurries,
·  spacer compositions,
·  and placement procedures.
·  Setting and strengthening times.
Preliminary designs are based on general good oil field practices and experience of
those operating in similar well/down-hole situations and circumstances.
As drilling progresses the slurry design and placement technique must then be further
optimised and tailored to meet the actual well conditions to achieve cementing
requirements. Special reference would be made to design aspects such as to BHST,
hole caliper, mud and formation properties, lost circulation, over pressurised zones,
permeable or salt formations etc.
Computerised simulations are then performed. Normal practices verifying that the
cement slurry properties to be used will meet necessary requirements and if not would
then be adjusted by laboratory testing using location samples of cement, additives and
mixing water. This testing would be completed in the cementing companies laboratory. |
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