Avoiding Top Out on Surface Casing
An operator was having issues with cement fall back on surface casing using their traditional cement supplier. These wells required top out jobs to remediate. On wells without cement returns to surface, the state was requiring bond logs to be run.
Improved Bond Logs on Intermediate Casing in North Dakota
Intermediate casings in the Williston Basin pose unique challenges to providing a quality cement bond log. Top of cement across the Dakota (a permeable, gas producing formation) is required. There are multiple salts, sands and shales, including the depleted Mission Canyon and over pressured Bakken and Three Forks formations. The drilling fluid is typically oil based to prevent washout of the salts. The casing is landed at 90 degrees, in either the Bakken or one of the Three Forks benches. These formations are high pressured, and produce gas and oil, which can lead to higher potential post placement annular fluid influx risk.
Cemented Horizontal Production Liners in Challenging Conditions
With bottom hole temperatures in excess of 250 oF, and total measure depth exceeding 20,000 feet, cementing production liners in the Williston Basin is a challenge. The target producing intervals are the Bakken and Three Forks formations. These wells are drilled underbalanced using brine to optimize penetration rates. Due to the high temperatures, long laterals, and slim hole design; fluid design is critical to the well.
Reducing Cost and Time on Remediation in Wyoming
An operator contacted ALTCem regarding holes in the production casing on an oil producing well in a water flooded field in Wyoming. The severity of the holes would not be known until an injection rate was established. ALTCem recommended a variable density slurry that could be adjusted on location. Once rigged up, the injection rate was identified as 2.5 bpm @ 900 psi. ALTCem recommended a thixotropic 13 lb/gal blend to ensure a good squeeze with adequate pump time.
Cost Savings on Technical Plug and Abandonment in Utah
An operator contacted ALTCem regarding a specialty plug and abandonment on a well in Utah. The well in question had 3.5” casing and 1.5” tubing was to be utilized as the working string. The abandonment procedure called for squeezes as well as cement plugs to be tagged. This required cements to be designed with low friction pressure, extended pump times and rapid compressive strength development. In order to ensure successful placement, ALTCem modeled the friction pressure with CEMPRO+ software and utilized Ultrasonic Cement Analyzers to determine compressive strength development.
40% Improvement in Production with Acid Treatment in Colorado
An operator contacted ALTCem with five wells in northern Colorado. ALTCem worked with the operator to analyze the wells and provide an acid remediation recommendation. Each well had a specific treatment designed to optimize the economics of the project.