Evaluating the effect of drill string rotation and change in drilling fluid viscosity on hole cleaning

Samuel Bright Olawale,Promise O Longe,Samuel Felix Ofesi

doi:10.1007/s13202-021-01209-y

Samuel Bright Olawale, Promise O Longe + Show 1 more

Open Access

https://doi.org/10.1007/s13202-021-01209-y

Copy DOI

Abstract

The most primitive hole challenge is cleaning the hole, which is more severe in deviated wells. This problem was tackled in this research via experimental analysis and graphical evaluations. To hit this aim, rheological parameters were experimentally obtained, and Noah’s model was used to determine cutting bed erosion time at varying heights. A graphical evaluation was done using a case study of deviated wells X and Y from a Niger Delta field. The result shows that low-viscosity fluid, KCL polymer fluid and high-viscosity fluid take 124, 283 and 342 min, respectively, to erode equal height as graphical evaluation shows that hole cleaning will grow complex on deviation. Thus, the deduction from this work in reducing non-productive time (NPT) related to hole cleaning in drilling operation is first, prior to making a trip, pumping low-viscosity fluid at a high flow rate. Secondly, during drilling, increasing drill string rotation in deviated wells can effectively stir the cuttings into the annulus above the low session of the hole.

Highlights

Hole cleaning, as one of the most important functions of drilling fluid, is defined as the transportation of drilled cuttings from the wellbore to the surface, and at the surface, the drilled cuttings are mechanically separated from the drilling fluid before it is re-circulated
The objective of this study is to functionally evaluate the effect of low-viscosity fluid and drill string rotation on hole cleaning
The effect of change in drilling fluid rheological properties with respect to hole cleaning can be further explained from the results obtained from the three models

Summary

Introduction

As one of the most important functions of drilling fluid, is defined as the transportation of drilled cuttings from the wellbore to the surface, and at the surface, the drilled cuttings are mechanically separated from the drilling fluid before it is re-circulated. As drilling progresses with increasing hole angle, there is a change in the movement of drilled cuttings from vertical to radial, thereby causing Boycott settling effect. As this bed is formed, failure to clear off the cutting bed can cause severe drilling problems such as stuck pipe, bit balling, premature bit wear, drag and excessive torque on the drill string, logging and cementing difficulties.

Objectives

Methods

Results

Conclusion