SU1435758A1 - Method of cementing producing strings of gas wells - Google Patents

Abstract

The invention relates to the oil and gas industry, and may be. used in cementing single-section production casing in wells. The goal is to increase the quality of cementing and protection of the subsoil from intra-shgastov flows. First, the intermediate column (K) is lowered into the well to the absorbing horizon with the planned hydraulic fracture. Then, the production K is lowered to the bottom of the wells and the cement mortar (CR) is pumped by direct casting. First, CRs are pumped into the shoe of an intermediate K direct zapivka, consisting of two portions. The first portion has a slower setting time compared with the second portion. The first portion is pumped lightweight cement slurry, the second portion is a cement slurry of normal flow. In the closest to the Bashmak, the intermediate K absorbing horizon, after the second portion is set, the fracture is performed. It is produced by creating pressure in the annulus due to the injection of drilling mud. The excess of CR from the shoe of intermediate K is wiped back into the nearest absorbing horizon by the drilling fluid before the time of loss of pumpability of the first CR is expired. Then CR is pumped into the annular space. The first portion of the CR contains a clogging additive. 3 il. S (LE 4 CO SP EL 00

Description

The invention relates to the mining industry, and more specifically to the oil and gas production, and can be used in cementing single-section production colonies in wells with a LOW5L gradient of hydraulic fracturing of rocks.

The aim of the invention is to improve the quality of csmented and the protection of the subsoil from in-situ flows,

FIG. isog razhetsa direct cementing scheme; ma 2, 2 — carrying out p-shroking and displacing the tamol solution and s of the intermediate column; FIG. 3 shows a reverse cementing scheme.

Initially, an interstitial column 1 up to. Of the horizon extends down the horizon from Sh.animyu; The operation of the column 2 is lowered in one section: about the bottom of the well. Cementova 11ia promzE5ODT in two stages. First, the cement mortar is applied with an entry into the shoe of the intermediate column by an ealkzku consisting of two portions, the first portion having a slower setting time compared with the second portion, i.e. the first portion is pumped with a lightweight TahinoHa.-ra-aM solution, the second portion is a tampoi-e:; -th solution of a normal fluid; before the pumping time of the first portion expires and after setting the second portion in the nearest - a horizontal fracture is performed by fracturing by creating pressure in the annulus by pumping mud from the mouth into the annulus and removing the cement mortar from the BONDS of the interstitial column: by backfilling into the nearest absorber Ayupday horizon drilling mud, C), about the expiration of the NIN time loss of penetration of the first portion of the cement slurry, after which the cement slurry is pumped into the annular space, the first portion of which contains:

Example. The production string is lowered into the well to a depth of 3000 m into the well. To ensure that the cement slurry rises to the top, the column is cemented in two stages. The first stage is cementing the columns.)

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: Pb by pouring two portions of cement slurry with a calculated rise of the cement slurry to 1,300 m, i.e. 74 m taller than a 245 mm intermediate column. The first portion of the 24 m solution for filling the annular space in the interval 1300-2500 m is prepared with a lightweight density of 1460 kg / m from a mixture of cement and 92% and 8% vermiculite for hot wells, Proc: cement slurry Oriented (. It lasts 4 hours. A second portion of cement mortar with a volume of .12 m to fill the annular prostration in the permafrost of 2500–3000 m. prepares Glotnosti i L20 kg / m,

11 rokachB, 1e; the awnness of the solution is compounded by the - - MZCHN,; iepc,:, with a portion of tampopazhmogog p ;. ; from the procuct solution, consisting of water and about 2% of the 1 single solution: GOTD, LroBALIvA tampy mortar is produced by the drilling raspor Yum with a density of 60 k- / m. After pumping 52.3 m of the drill bit from the stop at a pressure of 13.5.

The first 3 j an Х1емейтиэссван1: finish; article, dylenke pas tse1-: himGtiroBochinoy head reduced to cool,

After 45 kln after the first stage, cementing creates in the ex- :: luatacial colopnz an excess nutrenx pressure; -; 1 ig 10 kPa, eakr: - bilge unxversal: - th pretreatment centr and produce a hydraulic fracturing at 10 MPa pressure the annular space of the drilling fluid cement tyrosine - aggregates In the process of absorption, 2 m of brown mud is injected at npnei i-icTocTH 10 l / s. The pressure during pumping at the bottom of the plant is 6.5 ° C, Remaining a scoop on the PCR for 12 hours. During RFQ, thermometry is performed to determine the cement head as per the column from the direct method of cementing. After 12 hours, the second stage of cementing is carried out by reverse absorption. Inject H, 5 m of cement-cement solution densely — 1460 kg / m (first portion) and

25 M cement mortar density

1820 kg / m.

The pressure during the reverse cementing method on the absorption of 6.5 MPa with a capacity of 10 l / s. The end of injection is determined by increasing the pressure up to 8 MPa. According to ACC measurements, the cement behind the production column is raised to the mouth.

Claims (1)

Invention Formula A method of cementing production columns of gas wells, including running the intermediate column, injecting cement mortar by direct pouring, hydraulic fracturing of absorbing formations with drilling mud by creating pressure in the annulus with injection of the rest of the cement mortar by refilling, characterized in that, c. in order to improve the quality of cementing and the protection of the subsoil from in-situ flows, the injection of cement mortar by direct pouring is carried out in two portions with entering the shoe the first cement slurry has a slower setting time compared with the second batch, hydraulic fracturing is performed in the absorbing horizon closest to the intermediate column shoe after the second batch is set, and excess cement from the intermediate column shoe is displaced by the next absorbent horizon of the drilling fluid to the expiration of the loss of the first portion of cement mortar, after which the cement solution is pumped into the annular space, va portions which comprises kol- matting additive. 7 /// / 7 / /// u / /// 77 // 77/77 / 77/77 9i, 1 IG :. j; g; -; -Ri, gom