Nov. 12, 2008


Description

The ability to accurately predict the effect of drillpipe rotation on Equivalent Circulating Density (ECD) remains a challenge for those involved in engineering today's complex wells. In many of these challenging wells (extended-reach drilling, deepwater, HPHT, etc.), the safe drilling window between hole collapse and fracturing is often narrow. Accurate prediction of the effect of drillpipe rotational speed could allow better optimization of operational parameters in the drilling process, and hopefully reduce the incidence of violation of the safe drilling window.

Previously ECD results measured at different circulation rates and drillpipe rotational speeds were modeled and presented to the industry in SPE110470, presented at the 2007 SPE ATCE in Anaheim, California. The calculation methods involved several complex factors including estimated drillpipe eccentricity, nonlinear shear rate modeling coefficients, drillpipe geometry correction factors, etc. The presented results constituted the best-available correlation with direct downhole pressure measurements, but still showed improvement was needed.

After a review of the field data in hand, a new approach was taken to try to reduce the complexity of the calculations into a more easily-usable form. In this new predictive model, the diameter ratios and the rotation speed are used to predict pressure drop increase caused by the rotation of the drillpipe. This new calculation method is presented in the discussion. The modeled results show that this calculation technique can produce better prediction of field measurements of downhole pressure changes while rotating and is much simpler to use. Not only can it help in navigating through the safe drilling window, but it also can be used to separate pure rotation effects from other coupled wellbore events, such as hole cleaning and barite sag.


Featured Speakers

Speaker Juan Carlos Rojas / Terry Hemphill
Fluids Environmental Specialist / Global Advisor BP / Halliburton Juan Carlos Rojas Juan serves as the Drilling Fluids Advisor for BP's North and South America operations.  His previous positions include Team Leader for the Fluids group in Colombia and Fluids Specialist in London.  Juan Carlos Received a BS in Petroleum Engineering …

Fluids Environmental Specialist / Global Advisor
BP / Halliburton

Juan Carlos Rojas

Juan serves as the Drilling Fluids Advisor for BP's North and South America operations.  His previous positions include Team Leader for the Fluids group in Colombia and Fluids Specialist in London.  Juan Carlos Received a BS in Petroleum Engineering and Joined BP in 1994 as a Senior Fluids Engineer. Previously Juan Carlos worked six years for Baroid Drilling Fluids in Colombia and Ecuador.

 

Terry Hemphill

Terry serves as a Global Advisor for Halliburton in Houston. He specializes in the areas of drilling fluids rheology and hydraulics, barite sag, and wellbore stability. Terry received a BS in Chemistry from Rice University and has worked in the oilfield drilling fluids business since leaving university. He is a member of the SPE, American Rock Mechanics Association (ARMA), and the American Association of Drilling Engineers (AADE).




Full Description



Organizer

Kevin Brady


Date and Time

Wed, Nov. 12, 2008

11:30 a.m. - 1 p.m.
(GMT-0600) US/Central

Event has ended

Location

Greenspoint Club

16925 Northchase Drive
Houston, TX 77060