Drilling Mud and Cement Slurry Rheology Manual

The importance of rheological properties – i.e., of flow properties – of drilling fluids and cement slurries is now considered as self-evident.

During the drilling, the control of the “viscosity”, or the rheological characteristics, of the mud by simple and rapid methods has always been an indispensable guide for the technicians on the worksite, and has remained so to this day. In fact, flow properties directly affect the progress of the operations. Their proper adjustment ensures that the hole will be to gauge and that it will be drilled in the shortest possible time and under the best possible safety conditions.

In a similar manner, the efflciency with which the mud is displaced by cement slurry during cementing depends on the flow properties of the fluids involved.

Attempts at adjustment and optimization of rheological characteristics within the framework of other constraints may obviously involve laborious calculations. However, in recent years the treatment of the data has become much easier due to the use of modern computing techniques, in particular with programmable mini-computers.

The group “Drilling Fluids and Cements” of the French Technical Committee of the Chambre Syndicale de la Recherche et de la Production du Petrole et du Gaz N aturel wanted to compile data on rheology of fluids in a single manual, to be used by members of the profession.

This book is not primarily concerned with theory, regardless of the numerous equations it contains at the risk of discouraging the reader; its basic approach is practical. It has attempted to present a logical treatment which will be easy to apply in practice. As a result, certain computing methods were omitted, and precision sometimes had to be sacriflced to simplicity. However, no apology is made for the use of such approximations; in fact, any attempt at rigor would be doomed to failure, in view of the many inherent factors which do not lend themselves to quantitative treatment.

Chapter 1 deals with fundamental concepts.

Chapter 2 refers to the general principles involved in determining rheological parameters of drilling fluids and cement slurries.

Chapter 3 relates to practical methods for using the results obtained in the flrst two Chapters, in units employed on the worksite. It is primarily intended for technicians called upon to make “hydraulic” computations during drilling.

Chapter 4 contains several examples.