Baker Hughes, a GE company, has announced the introduction of its DELTA-TEQ™ low-pressure-impact drilling fluid, a non-aqueous formulation that enables operators working in narrow pressure windows to meet their drilling objectives by significantly reducing the risks associated with this activity.
In challenging wells, like those offshore, pore pressure, fracture gradient, and complex geometry combine to create a narrow operating window. Numerous operational problems such as excessive surge pressures, pressure spikes due to pump initiation pressures, complicated equivalent circulating density (ECD) management, and the inability to effectively control drilling parameters, can result in costly and time-consuming events.
“The typical solution to drilling in narrow pressure windows has been the use of a low-ECD drilling fluid,” said Clive Rayton, vice president, BHGE Drilling and Completion Fluids. “These fluids can mitigate some of the drilling risks, but not enough of the risks to reliably or efficiently meet all drilling objectives. The DELTA-TEQ fluid is the best solution for extending the critical drilling window.”
Featuring an advanced formulation of specialised clay and polymers, the DELTA-TEQ fluid creates a non-progressive gel structure that reduces hydraulic impact with a rapid-set/easy-break profile. This profile maintains fluid integrity if operations are paused, mitigates pressure spikes when circulation resumes, and protects the formation from surge pressures when running casing.
In addition, the DELTA-TEQ fluid has the unique ability to manage hydraulic impact by maintaining the right viscosity in the right areas of the well for optimal hole cleaning and penetration rates without putting excess pressure on the formation. Like a “viscosity clutch,” it engages viscosity at low shear rates and disengages at high shear rates.
Recently, an independent national oil company deployed the DELTA-TEQ fluid in a challenging deepwater project in Brazil. The fluid retained its stability throughout a 655 m interval and enabled the operator to reach the section’s final measured depth at 2822 m — marking the entry into the reservoir with stable borehole conditions and no downhole losses. The DELTA-TEQ fluid allowed the operator to increase flowrate by 14% and rate of penetration by 48% compared to offset wells, without significantly impacting pump pressure, equivalent circulating density, and torque and drag. Furthermore, the system reduced annular pressure variations by 47% compared to offsets, confirming the low-impact characteristics of the fluid.
Read the article online at: https://www.oilfieldtechnology.com/drilling-and-production/09052019/bhge-introduces-low-pressure-impact-drilling-fluid/