Shutoff method preventing inflow of formation water
Russian Federation patent № 2127807 granted April 9, 1998. This invention is related to the development of oil and gas fields and may be used to isolate depleted reservoirs in producing wells.
This method permits plugging only the water inflow section of the bed, without decreasing filtration parameters of its productive areas. It works by creating a gas-liquid elastic barrier above the plugged zone.
Well construction completion method
Russian Federation patent № 2134341 granted December 9, 1998. This invention is related to development of oil and gas fields and may be used to open the productive bed and install filters in its intervals in the production strings during well completion.
The use of filters with plugs, which are then destroyed by chemical agents, eliminates perforation operations in the well, controls the quality of the exposure of the productive bed during well completion, and combines the latter with well development.
Well screen
Russian Federation patent № 2143056 granted March 25, 1999. This invention is related to development of oil and gas fields and may be used to equip production casing strings with screens during well completion.
The well screen consists of a tubular body with apertures that have been closed with plugs; each of the plugs contains a bush with a core. The tubular body is fitted with centralizers uniformly arranged along its length. The plugs’ bushes are connected firmly to the body and the cores are similarly connected to the bushes. From the inside, the cores are concave; on the outside of the body’s surface, they are cone-shaped and protruding. The cores of the plugs are made of material that is destroyed when exposed to chemical agents.
Method for after-production opening of productive beds
Russian Federation patent № 2143057 granted March 25, 1999. This invention is related to development of fields containing formation fluids (oil, gas, water, and other) and may be used during exploitation of multihorizon fields.
During well drilling, when intermediate and production strings are lowered and plugged, filters with plugs are fitted opposite each productive bed. These filter-plug elements are later destroyed with chemical agents. The filters are equipped with centralizers and, in the course of plugging the space between the strings of the filter, the intervals are filled with a special non-hardening cement. After-production opening of productive beds is effected by successive destruction of the filter plugs and removal of the non-hardening cement from the space between the strings.
Plugging mixture
Russian Federation patent № 2154729 dated December 2, 1999. This invention is related to oil and gas production, specifically to materials used to stabilize producing formations of oil, gas, gas-condensate, and other wells.
The invention has two objectives: to reduce gas formation when forcing the plugging mixture into the well and to increase the penetrability of the hardened cement when treated with an alkaline media.
The plugging mixture contains Portland cement and an aluminum grit additive; the cement makes up 88 percent to 96 percent of the mass and the balance is aluminum grit.
Plugging material
Russian Federation patent № 2154730 granted December 2, 1999. This invention is related to oil and gas production and may be used to stabilize producing formations of oil, gas, gas-condensate, and other wells.
The invention was conceived as a way to extend the period of pumpability of plugging material and to increase of the penetrability of the hardened cement when treated with an alkaline media.
The plugging material consists of binding material and a siliceous additive – exhaust silica gel. The silica gel is used at the stage of absorption dehydration of natural gas in the following proportions: a binder at 80 percent to 95 percent of the mass and the balance, exhaust silica gel.
