Poly Plug Texas Panhandle
Well Information
Operator: Noble Energy
Location: Texas Panhandle
Challenge
The brown dolomite in the Texas panhandle area varies in depth and the degree of losses. The dolomite section can be more than 3500 ft. and losses can range from seepage to complete loss of returns. Operators use different types of LCM and concentrations to prevent losses while drilling vertical wells. When losses are large, the typical LCM is a combination of cottonseed hulls and very coarse fiber.
Directional wells require a different solution, as directional tools do not work well with the LCM used to seal the dolomite section. Noble Energy looked for a solution that would seal the dolomite section, reduce the LCM type and concentration to allow directional tools to work efficiently and not require cement or an added casing string.
Solution
Poly Plug® PH
Engineering decided to use Poly Plug® PH, a cross linked polymer gel with a combination of solids, to seal the dolomite section. With the dolomite section sealed, directional drilling could be done with a minimum of small sized LCM and a minimum of time fighting lost circulation and cleaning tools.
The dolomite section was drilled with a mix of LCM in the mud. Once through the dolomite section drilling operations were halted and Poly Plug® PH was spotted across the entire dolomite section. Sufficient extra gel was available to allow squeezing the gel into the formation and across the entire zone. After squeezing and allowing the gel to set, the open hole was cleared and the lower direction portion of the well was completed.
After mixing, the Poly Plug® PH was displaced through an open-ended drill pipe as a balanced pill while on bottom. The drill pipe was pulled above the gel and the gel was squeezed into the formation. Squeeze pressures as high as 500 psi are possible with the cross-linked Poly Plug® PH gel. The well was shut in, allowing the pressure to bleed off to the formation. After several squeezes to allow good penetration into the formation and time for the gel to set, the LCM was screened out of the system and the drill string POOH.
The new BHA was picked up and RIH. Prior to further drilling, a successful FIT test was performed and the well was completed with standard tools and practices.
Results
Using Poly Plug® PH saved Noble Energy costly rig days, allowed the well to be put into production sooner and provided extra days within their drill program to drill additional wells.