Techniques Cemented Liner Through High-Pressure Salt Section With Narrow Pressure Window, Mitigated Losses
Objectives
Manage well pressure during the entire well program, including drilling, tripping, and running the liner with a narrow operating window, and eliminating losses/influxes through a high-pressured salt section.
Minimize losses and influxes while cementing the 7 1/4-in. liner and improve wellbore integrity.
Our Approach
The Weatherford team deployed the PressurePro system, using a set-point choke, Coriolis flowmeter, and Model 7100 rotating control device (RCD) to enable managed pressure drilling (MPD) and managed pressure cementing (MPC) techniques.
The team was able to develop and execute the first full MPC operation in this field while following the pumping schedule throughout the cement job to navigate between a 0.2 ppg margin of well losses and gains.
Mud weight (MW) was reduced below the normal salt section MW, losses were managed, and adequate surface backpressure was applied to avoid being underbalanced, which can result in salt creep and/or an influx in this section.
Value to Customer
Managed pressure cementing provided the ability to improve zonal isolation by cementing the 7 1/4 –in. liner in an extremely narrow downhole window with a pressure margin of approximately 0.2 ppg.
Application of MPD techniques allowed Weatherford to handle and mitigate significant losses while drilling and cementing, and to obtain a strong shoe for further drilling to total depth (TD).
This technology will be an enabler for the customer in the future, ensuring wells meet specific objectives and minimizing nonproductive time (NPT) events.