Poly Plug Pan Handle Byers 2308P
Well Information
Canadian, Tx
WBM
9.0 lb/gal
130-150 F
180 min
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. Directional wells
require a different solution. Directional tools do not work well with the LCM used to
seal the dolomite section. The typical LCM is a combination of cotton seed hulls
and very course fiber when losses are large. 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. Engineering decided use 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 is drilled with a mix
of LCM in the mud. Once through the dolomite section they stop. The Poly Plug®
gel is then spotted across the entire dolomite section. Sufficient extra gel is
available to allow squeezing the gel into the formation across the entire zone. After
squeezing and allowing the gel to set, the open hole is cleared and the lower
direction portion completed. The volume of Poly Plug® Pan Handle used varies with
the height of the dolomite section but the procedures are about the same. After
mixing, the Poly Plug® Pan Handle is displaced down the drill pipe and through the
bit. The drill pipe is pulled above the gel and the gel is squeezed into the formation.
Squeeze pressures as high as 500 psi are possible with the cross linked Poly Plug®
Pan Handle gel. The well is 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, usually (6) hours. The cross-linked gel is tested before it is
washed through along with a final FIT prior to drilling ahead. Once through the gel
covered zone, coarse LCM is screened out of the hole and drilling continue using
standard tools and practices.
Results
Noble Energy has found that the procedure saves costly rig days,
allows the well to be put into production sooner and provides extra
days within their drill program to drill additional wells if desired with
both days and money saved.