DI-75 – Drill-In Fluids – A Study of Formation Damage Caused By Drilling at Downhole Temperatures and Pressures

By Drilling at Downhole Temperatures and Pressures”

Date Submitted: November 10, 1997

Technical Area: Production

Sponsor: NA

Title: Drill-In Fluids – A Study of Formation Damage Caused By Drilling at Downhole Temperatures and Pressures

Submitted by: O’Brien-Goins-Simpson & Assoc., Inc. 6430 Hillcroft, Suite 112 Houston, TX 77081 (713) 270-1192

Principal Investigator(s): Jay P. Simpson and Thad O. Walker/ ogsh@aol.com

Business Impact: Protection against formation damage while drilling is of extreme importance in horizontal wells because the open-hole completions provide no perforations to by-pass any near-wellbore blockage. Any mud solids invasion or external mud filter cake must be removed by well flow or by treatments to obtain good productivity. Today much time and expense are being directed toward the design of drill-in fluids with particle sizes to bridge pores at the rock surface to form an external cake and avoid solids invasion. The formulation of the drill-in fluids is based on permeability tests made with exposure of the rock under static and/or flowing conditions but do not include the actual drilling of the rock under downhole conditions of temperature and pressures. Drill-in fluid design without the complete simulation can be misleading, failing to provide the desired protection or even contributing to greater formation damage.

Technical Objectives: It is proposed to build laboratory equipment to study the complete drill-in, filtration (both dyna