Page 427 - Practical Well Planning and Drilling Manual

Section 3 revised 11/00/bc 1/17/01 12:00 PM Page 403

3.5.6
Cementing [ ]

simple cement bond log/variable density log is run to evaluate casing
to cement and cement to formation bonding. In more critical cases a
cement evaluation tool or ultrasonic indicator tool give more informa-
tion and can show channeling, microannuli, and other problems—but
at a much higher cost.
The job itself should be accurately recorded using chart recorders,
computers, and text reports. See the next topic for ensuring that all
pertinent information is recorded.

3.5.6. Field Cementing Quality Control Procedures

These procedures are designed to meet two objectives. The first
objective is to do everything possible to ensure that cement jobs are
carried out as intended with no problems. The second objective is to
ensure that if problems do arise, the information necessary to analyze
what went wrong is available.
The cement recipe sent to the rig should state quantities of cement,
mix water, and additives in words as well as figures. This simple check
avoids a bad fax from being misread to mix the wrong quantities. The
recipe should also state the total mix fluid when all additives have been
mixed, as a final check.
Ensure that the rig has available proper sample containers with
secure screw-top lids and labels. Pilot tests on the rig site should be
done with whatever equipment is available to you.

Pre-job actions.

1. Send in samples of mud, potable, and drill water to the cementing
laboratory every two weeks and additional samples as requested.
2. When the recipe fax is received from town, carry out the following:
a) Check that all quantities to be used are clear in the fax, clarify
with the drilling office if any are not clear
b) Calculate estimated material requirements and ensure that they
are available on the rig site, normally with 100% excess available
c) Check the total mix fluid requirement from your calculations
against the recipe (this is given automatically in the “well-
calc.xls” spreadsheet [you can copy this from the web site
library page at http://www.drillers.com])

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