FI66422C - SNABBT HAERDANDE TORR TAETNINGSBLANDNING FOER ELIMINERING AV PROBLEM I SAMBAND MED BORRHAOL OCH FOERFARANDE FOER FRAMSTAELLNING AV BLANDNINGEN - Google Patents

Description

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(51) egglflmxx2 C 09 K 3/10, C 0 * 4 B 7/35 FINLAND-FINLAND pi) 79211 «m H * ..» », - ,. ·». · ... ·. OH.07.79 (23) AHcapflM —- GHciglwtadag 0 * 4. 07.79 (41) TwBt tutorial - BIMt pffwdlg 07.01.80 «Bssriaasaaa» · <* · «(32) (33) (31) Py ^ Ftty» «» to. B> tfH prtorim 06.07.78 12.07.78 USSR (SU) 2631355, 2631356 (71) Terri torialnoe Geologicheskoe Upravlenie Tsentralnykh Raionov,

Roschinskaya ulitsa 10, Moscow,

Severo-Zapadnoe Territorialnoe Geologicheskoe Upravlenie, ulitsa Gertsena 59, Leningrad, USSR (SU) (72) Viktor Filippovich Rogov, Moscow,

Nikolai Konstantinovich Lipatov, Apatity Murmansk Oblast,

Ruben Armenovich Tatevosian, Moscow,

Mikhail Yakovlevich Titov, Moscow,

Lev Alexandrovich Tereschenko, Leningrad,

Arian Mikhailovich Yakovlev, Leningrad, USSR (SU) (7 * 4) Oy Koi ster Ab (5 * 0 Fast-curing dry sealing compound for the elimination of problems in boreholes and the method for its preparation - for use in the manufacture of foodstuffs for human consumption

The invention relates to the drilling of holes and in particular to a fast-curing sealing mixture for eliminating the difficulties of a borehole and to a method for producing a sealing mixture.

The invention can be used in geological surveys, in the civil engineering, oil and gas production, and drilling and blasting operations to remove disturbances due to soil, including flushing fluid absorption, water inflow, or an unstable intermediate area of holes, by zoning.

A dry sealant composition for removing borehole dents is previously known, which mixture is prepared on the basis of a powdered gypsum-cement binder containing 40 to 50% by weight of alumina cement and 50 to 60% by weight of gypsum or alabaster.

This known mixture must be applied dry to the awkward 2,6422 zones of the borehole and prepared on site on the borehole walls to form a liner.

Once the mixture is made and the liner formed, the drilling tools are pulled out of the hole to feed a new dose of mixture or to continue drilling the hole.

When the drilling tool is pulled out, the so-called piston effect, i.e. a vacuum develops under the tool, causing a pressure drop in the fluid inside or outside the liner, leaving a high hydrostatic pressure outside the liner but dropping inside the liner.

Unilateral pressure contributes to the damage to the liner because the fast-curing alloy from which the liner is made does not have sufficient strength or sufficient bond to the stones that form the walls of the hole.

The piston effect may cause the liner to completely detach from the walls of the hole and crack.

The same can be caused by vibrations or pressure pulses in the medium due to the rotation of the drilling tool and the drill rod when drilling a rapidly curable sealant mixture of known compositions which is not sufficiently strengthened in a few minutes to eliminate borehole disturbances.

In addition, the dry fast-curing sealant mixture soon loses its activity when stored due to the effect of moisture in the ambient air on the cement and gypsum.

The known fast-curing dry sealant mixture is obtained by mechanically mixing powdered cement and gypsum or alabaster in proportion.

However, this said mixing method does not achieve the required uniform distribution of cement and gypsum or alabast & fl throughout the mixture, which results in failure of the structure of the artificial stone lining to be formed, leaching of the lining material and thus rapid loss of tightness (after two or three days).

In addition, the previously used method for preparing a known dry mixture does not offer opportunities for its improvement, as it seems impossible to add the necessary additives in small amounts and distribute them evenly throughout the mixture.

The object of the invention is to provide a fast-curing dry sealant mixture for the elimination of borehole disturbances and a process for preparing the mixture which guarantees the required rate of hardening, strong bonding of the mixture to the rock forming the hole walls and extended storage time even under unfavorable conditions using special evenly distributed additives.

According to the invention, this object is achieved by adding 0.01% by weight of a fast-setting dry sealant mixture based on a powdered gypsum-cement binder using 40-50% by weight of cement and 50-60% by weight of gypsum or alabaster to the above. barium hexapherite powder having a grain size corresponding to the grain size of the binder.

It is preferred to add 5-15% by weight of silica gel to the mixture.

The invention also provides a method for for the preparation of a mixture in which a gypsum-cement binder is obtained by mechanically mixing together powdered cement and gypsum or alabaster in the required proportions and characterized in that said components are mixed together in an alternating electromagnetic field while barium hexferrite powder is added i.e. pellets made on the basis of barium hexapherite.

It is recommended to use pellets made of barium hexferrite alone.

It is equally preferred to use pellets made from barium hexferrite and inert additives.

It is recommended to use at least in part pellets with high shear wear.

The fast-curing dry sealant mixture according to the invention for the elimination of borehole disturbances and the method of its preparation guarantee the desired rate of hardening, good adhesion to the rock forming the walls of the hole and a long storage time even under unfavorable conditions.

Said sealant mixture is prepared on the basis of a gypsum-cement binder, which contains 40-50% by weight of cement and 50-60% by weight of gypsum or alabaster.

In addition, the mixture contains 0.01 to 3.0% by weight of powdered barium hexapherite having a grain size corresponding to the grain size of the binder.

A mixture of less than 0.01% by weight of barium hexferrite does not provide the desired strength and bonding.

If, on the other hand, the mixture contains more than 3% by weight of barium hexa-ferrite, the curing begins substantially more slowly and the strength of the lining decreases.

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An additional 5-15% by weight of silica gel can be added to the mixture, either as a powder or as pellets.

The addition of silica gel prolongs the shelf life of the mixture.

The fast-curing dry sealant mixture according to the invention is prepared as follows. The powdered cement and gypsum or alabaster are mixed in proportion in the chamber in an alternating electromagnetic mechanism. The addition of barium hexapherite to the mixture occurs due to the abrasion wear of the pellets during mixing in the chamber.

Barium hexaferrite pellets can be prepared either from barium hexaferrite alone or from this and inert additives. It has proven advantageous that at least some of the pellets have a high abrasion wear.

The invention is described below with reference to the following illustrative examples. The properties of the mixture are shown in Tables 1-3 of the Examples.

Example 1

The components of the mixture, 50% by weight of cement and 50% by weight of alabaster in an amount of 2 kg, were placed in a 100 mm diameter cylindrical chamber containing 500 g of magnetized barium hexferritite balls, 5 mm in diameter.

Around the chamber was a solenoid of electromagnet, i.e. a solenoid with a cross-sectional height of 80 mm and a width of 45 mm with a twisted copper wire thickness of 2 mm.

When 220 V 50 Hz mains power was connected to the electromagnetic coil, the magnetized balls, i.e. pellets, moved in a chaotic manner and thus mixed the components of the mixture in the chamber.

After a treatment time of 10 seconds, a mixture containing% by weight was obtained.

alabaster 49,995 cement 49,995 barium hexapherite 0.01

Example 2

To increase the barium hexapherite content to the remaining pellets, 497.8 g (Example 1), 100 g of similar pellets with higher abrasion wear (prepared at a temperature below 50 ° C of the recommended 1250 ° C) were added.

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All other parameters of the process remained unchanged. After a treatment time of 10 seconds, the following mixture was obtained containing% by weight: alabaster 49.95 cement 49.95 barium gexferrite 0.1

Example 3 After a treatment period of 2 kg of a mixture containing 50% by weight of cement and 50% by weight of alabaster, the following mixture with the following composition (in% by weight) of cement was obtained: 49.5 alabaster 49.5 barium hexapherite 0.1

All other parameters of the process described in Example 1 were unchanged.

Example 4 After 10 seconds treatment of a mixture of 2 kg of 50% by weight of cement and 50% by weight of alabaster, a mixture was obtained having the following composition in% by weight: alabaster 48.5 cement 48, 5 barium hexapherite 3.0

The curing time and strength of the above mixtures in uniaxial compression were then determined.

The curing time of the mixtures was tested by the Vicat needle method and strength tests in uniaxial compression were performed using 7x7x7 cm cubes. The test results are listed in the following table.

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table 1

Curing time and strength of the sealing mixture in uniaxial compression, 2 kg / cm

For example, the composition of the mixture- 'Kbetting- Strength in uniaxial press: timing, kg / an = c, start end curing conditions alabaster .., _ Ä (min) (min) air hydraulic

Af bariurhexa ferrite = pailK> "% lh 2 h 3 h 4 h 5h 6h 1. Comparative C - 50 sample Λ - 50 6 8 17 26 70 22 20 75 2. Example 1 C - 49.995 Λ - 49.995 H - 0.01 7 9 18 26 70 25 20 75 3. Example 2 g - 49.95 A - 49.95 K - 0.01 14 15 60 148 198 75 70 180 4. Example 3 C- 49.5 A - 49.5 H - 1.0 14 16 27 56 - 5. Example 4 C - 48.5 A - 48.5 K - 5.0 20 25 18 22

As is clear from the table, the best physicochemical properties are in the sealant mixture, which contains 49.94% by weight of cement, 4995% by weight of alabaster and 0.1% by weight of barium hexaferite.

The concentrate work, which contains 49,995% by weight of cement, the same amount of alabaster and 0.01% by weight of barium hexaferrite, differs very little in properties from the control sample, while the concentrate work, which contains 48.5% by weight of cement, 48.5% by weight, -% alabaster and 3.0% by weight barium hexferritite, has a significantly longer curing time and lower strength.

Thus, the additional tests concerned a sealant mixture with the best physicochemical properties, i.e. a mixture containing 49.95% by weight of cement, 49.95% by weight of alabaster and 0.1% by weight of barium hexaferrite.

The results of the tests on the bond strength (tensile strength) of cement stone to rock are listed in Table 2, where C = cement, A = alabaster and H = barium hexaferrite.

Table 2 2

Binding strength of cement stone (tensile strength, g / cm) to rock.

Mixture of basalt quartz listvenite limestone sandstone 'contact time, min. touch time, min. touch time, min.

weight * 5 10 15 20 5 10 15 20 5 10 15 20

Reference mixture C-50 3.18 6.5 14.4 19.0 3.18 6.7 15.4 22.2 3.21 6.9 14.5 24.1 A -50 C-49.95 A-49.95 H- 0.1 1.98 6.3 15.4 40.9 2.4 6.5 17.5 46.0 2.8 7.5 22.1 56.3

Due to the high activity of the sealant mixture according to the invention and the problems associated with its storage during geological exploration trips, some silica gel is added to the mixture in the form of both powder and pellets or a mixture thereof.

The change in properties of the concentrate mixture containing 49.95% cement, equal amounts of alabaster and 0.1% by weight barium hexferrite stored under arctic conditions is reported in Table 3.

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Table 3

Changes in the properties of the sealant mixture stored under Arctic conditions

Example Silica Fragility Compressive strength pro- number in gel additives starting / wt% from 0, 12 24 0 6 12 24 month month month month month month month month

Comparison - good bad bad bad 100 40 1 5 good good fair. bad 100 100 80 30 2 10 good good good fair. 100 100 100 80 3 15 good good good good 100 100 100 100 4 20 good good good good 80 80

The table clearly shows that the mixture containing 5% by weight of silica gel retains its physicochemical properties for up to 1 year, after which they substantially deteriorate.

On the other hand, the addition of 20% of silica gel causes a decrease in the strength of the cement stone, so that the optimum silica gel content must be considered to be 15% by weight.

Claims (6)

66422 A fast-curing dry sealant mixture for removing borehole holes prepared on the basis of a powdered gypsum-cement binder containing 40-50% by weight of cement and 50-60% by weight of gypsum or alabaster, characterized in that it contains 0 .01 to 3.0% by weight of powdered barium hexapherite having a grain size corresponding to the grain size of the binder. Mixture according to Claim 1, characterized in that it contains 5 to 15% by weight of silica gel. A process for preparing a mixture according to claims 1 and 2, wherein the gypsum-cement binder is obtained by mechanically mixing powdered cement and gypsum or alabaster in a desired ratio, characterized in that the mixing is carried out in an alternating electromagnetic field while barium hexapherite-based pellets or spheres. Process according to Claim 3, characterized in that the pellets used are made exclusively of barium hexa-ferrite. Process according to Claim 3, characterized in that the pellets used are made of barium hexapherite and inert additives. Method according to Claim 4 or 5, characterized in that some pellets have a higher abrasion wear than others.