Scope of Application
This technology is suitable for offshore
and onshore formation sand control when sand production is caused by
unconsolidation, high oil and gas drainage pressure, high viscosity crude oil,
depleted zones and incursion of extraneous fluids. For the gravel packing in
the open holes, the size of the hole must exceed 6-1/2"; and for gravel
packing in the screen of casing, the size of the casing must exceed
5-1/2".
Technical Principle
Stand-alone screen sand control mainly
depends on the gap spacing created when the screen was manufactured, which is
able to keep out sand particles bigger
than the gap spacing, however, formation sand particles smaller the gap spacing
can still pass into the well. Different types of screens can be chosen
according to various sand producing tolerance and cost budgeting.
Gravel packing technology is using ceramic
proppants to fill the space between the screens and the formation; therefore,
ceramic proppants with size bigger than the screens’ spacing will not enter
into the shaft while smaller spacing between ceramic proppants will ward off
formation sand with different sizes, so as to build the second filter screen.
And the third filter screen is built by the accumulation of the formation sand
with different sizes outside the ceramic proppant layer to ward off much
smaller formation sand particles.
Diagram of Packer Screen Tools
Assembly Diagram for Gravel Packing Service Tools
Main tools:
① Top packer
assembly – setting pressure: 3500psi.
② Screen – wire
wrapped screen with adjustable wire-winding spacing and big open area which can
be up to 10%.
③ Bottom sump
packer assembly – using hydraulic setting with temperature resistance of 149 ℃;
④ Service
tool assembly – switchable gravel-pack sliding sleeve which can provide 2-3/8"
return passage.
Technical Features:
(1)Effective formation sand control with the period of validity above 180 days;
(3)Safe and reliable with mature technology
application.
Service Ability and Performance:
As of June 2013, the company has completed formation sand control for 72 wells domestically with 100% effective rate. Operations include several formation sand control processes, for example: stand-alone screen sand control, high rate water pack (HRWP) sand control, micro frac-packing sand control, frac-packing sand control and open hole horizontal well gravel-packing sand control.