Page 273 - Practical Well Planning and Drilling Manual

Section 2 revised 11/00/bc 1/17/01 12:04 PM Page 249

2.5.13
Drilling Fluids Program [ ]

back-up services. With regard to engineering, often an inexperienced
or unqualified engineer can make a poor job of a good mud program,
and yet a good engineer can turn around a poor program or succeed
even with a lack of appropriate or high quality materials.
Quality of materials is an important factor. Most reputable major
drilling fluids companies have their own specifications that they apply
in supplying material. The mud companies reputation is more impor-
tant (in regards to repeat business) than any quick short-term gain
from supply of inferior products. However, some mud vendors, espe-
cially in third world countries, can find plenty of ways to make extra
profit at your expense. The basic problem at the tender stage is ensur-
ing that you specify exactly what is acceptable to you. Many major oil
companies have their own “in-house” specifications, which can make
the tendering process easier because they can be included as specifica-
tions in the scope of work. The vendors know exactly the specification
that they are bidding on. It is worthwhile to get a drilling fluids expert
to look at the wells you are likely to drill and write out a tender to
ensure that you have recourse against the vendor if inferior products
are supplied. Following are a few, but by no means all, of the materials
that may be specified:
All barite must meet at least API 13 A specification. The vendor
should state the country of origin and other specifications that
barite will pass. Barite can be tested to ascertain that it will meet the
stated specifications.
Bulk bentonite should meet at least API 13 A specification for
European bentonites if it is to be used in spud muds. Sack bentonite is
recommended to meet API 13 A specification for Wyoming bentonites
if it is used as a component of mud systems other than spud muds. The
vendor should state the country of origin in each case.
Many polymers are supplied in liquid form (as a suspension in a
carrier oil). The percentage activity or purity should be stated,
which will allow you to compare the actual amount of active chem-
ical per dollar.

Polyacrylate deflocculant liquid; state % of activity
PHPA, liquid; state % of activity
HEC, liquid; state % of activity
Salts (such as sodium chloride) should have the degree of purity
stated

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