Curing mold for compressive strength of set cement

Abstract

The utility model discloses a cement stone compressive strength maintenance mold, which relates to the technical field of dismounting tools and comprises a mold body formed by encircling two mold pieces in bilateral symmetry. The mold body is provided with a first end cover groove used for installing a first end cover, a second end cover groove used for installing a second end cover, a mold testing cavity located between the first end cover and the second end cover and provided with a containing space, a slurry injection opening communicating with the mold testing cavity and located in the top of the mold body, and a slurry containing groove communicating with the slurry injection opening. Prepared cement paste is injected into the film testing cavity through the grouting opening and overflows to a certain depth of the paste containing groove, the cement paste is placed into a high-temperature and high-pressure thickening instrument to be cured in cooperation with the high-temperature and high-pressure thickening paste cup, the cement paste overflowing into the paste containing groove can supplement the cement paste in the film testing cavity, the shrinkage rate of set cement is reduced, and the cement paste can be recycled. The well cementation cement stone compressive strength maintenance mold can be put into a high-temperature and high-pressure thickening instrument kettle for maintenance so as to simulate the compressive strength of maintenance cement paste under the design pressure of well cementation.

Description

Technical Field

[0001] The utility model relates to the technical field of disassembly tools, in particular to a curing mold for the compressive strength of cement stone. Background Art

[0002] When conducting the compressive strength test of cement slurry according to API "Test Method for Well Cement", the cement stone mold is placed in a curing autoclave, and the cement slurry is cured under a pressure of 20.7 MPa at the final test temperature. In actual well cementing, the designed pressure of the cement slurry is mostly higher than 20.7 MPa. The designed pressure requirement of the cement slurry in Yuan Shen 1 well reaches 165 MPa. In order to better simulate the influence of pressure on the compressive strength of cement stone, it is necessary to cure the strength of the cement slurry under the designed pressure.

[0003] At present, the maximum working pressure of the existing high-pressure curing autoclave is 35 MPa, which cannot well meet the curing requirements under the well cementing designed pressure. The test pressure of the 8040 high-temperature and high-pressure thickening instrument can reach 275 MPa, and the pressure is stable during the test. Using the high-temperature and high-pressure thickening instrument to cure the strength of the cement slurry can more intuitively understand the compressive strength of the cement stone under high temperature and high pressure. However, the size of the existing curing mold for the compressive strength of cement stone fits the inner diameter of the curing autoclave, while the inner diameter of the high-temperature and high-pressure thickening instrument autoclave is smaller than that of the curing autoclave, and the existing curing mold cannot be applied in the high-temperature and high-pressure thickening instrument autoclave.

[0004] In summary, how to design a curing mold applicable to the high-temperature and high-pressure thickening instrument autoclave to simulate the curing of the compressive strength of cement slurry under the well cementing designed pressure has become an urgent problem to be solved by those skilled in the art. Content of the Utility Model

[0005] The purpose of the utility model is to provide a curing mold for the compressive strength of cement stone, which is applicable to the high-temperature and high-pressure thickening instrument autoclave to simulate the curing of the compressive strength of cement slurry under the well cementing designed pressure.

[0006] To achieve the above purpose, the utility model provides a curing mold for the compressive strength of cement stone, including a mold body formed by enclosing two symmetric mold parts on the left and right. The mold body is provided with a first end cover groove for installing a first end cover, a second end cover groove for installing a second end cover, a test mold cavity located between the first end cover and the second end cover and having an accommodation space, a grouting port communicated with the test mold cavity and located at the top of the mold body, and a slurry containing groove communicated with the grouting port.

[0007] Preferably, the top of the mold body includes a top surface, on which there is a first protrusion. The middle part of the first protrusion is recessed inward to form a slurry containing groove. The slurry containing groove is an inverted frustum-shaped groove, and the bottom of the slurry containing groove is communicated with the top of the grouting port.

[0008] Preferably, the first protrusion includes:

[0009] The first abutting surface, which is parallel to the top surface and is at a height higher than the top surface;

[0010] The outer circumferential surface, which is connected to the top surface and the first abutting surface;

[0011] The inner circumferential surface, which is connected to the first abutting surface, and one end of the inner circumferential surface away from the first abutting surface is at a height lower than the top surface.

[0012] Preferably, the first protrusion is further provided with a through-type second groove, and the second groove communicates with the slurry containing groove, and the bottom of the second groove is at a height higher than or equal to the height of the top surface.

[0013] Preferably, the cross-section of the outer circumferential surface perpendicular to the axis of the mold body is circular, and the diameter of the circle gradually increases in the direction from the first abutting surface to the top surface;

[0014] The bottom of the mold body includes a bottom surface parallel to the top surface, and a second protrusion is provided on the bottom surface. The second protrusion includes a second abutting surface parallel to the bottom surface and two second circumferential surfaces connected to the second abutting surface and the bottom surface. The distance between the first abutting surface and the top surface is equal to the distance between the second abutting surface and the bottom surface. The second abutting surface is a ring, and the inner diameter of the ring is greater than or equal to the diameter of the largest circle in the outer circumferential surface, so that the first protrusion and the second protrusion on the opposite sides of two adjacent mold bodies up and down can fit together.

[0015] Preferably, the cross-section of the grouting port perpendicular to the axis of the mold body is rectangular.

[0016] Preferably, both the first end cover and the second end cover include:

[0017] The first cylinder, whose circumferential surface abuts against the first end cover groove or the second end cover groove;

[0018] The second cylinder, which is arranged on the side of the first cylinder away from the test mold cavity. The diameter of the second cylinder is smaller than that of the first cylinder, and the circumferential surface of the second cylinder abuts against the mold part;

[0019] The handle, which is arranged on the side of the second cylinder away from the first cylinder and is located in the middle of the second cylinder.

[0020] Preferably, both mold parts are provided with a plurality of connection holes, and the corresponding connection holes are axially aligned, and the connecting piece can pass through the corresponding connection holes to fixedly connect the two mold parts.

[0021] Preferably, the outer shape of the test mold cavity is a cylindrical structure, and the axis of the cylindrical structure is perpendicular to the axis of the mold body.

[0022] Compared with the above background art, the cement stone compressive strength curing mold provided by the present utility model includes a mold body formed by enclosing two symmetric mold parts on the left and right. The mold body is provided with a first end cap groove for installing a first end cap, a second end cap groove for installing a second end cap, a test mold cavity located between the first end cap and the second end cap and having an accommodation space, a grouting port communicated with the test mold cavity and located at the top of the mold body, and a slurry containing groove communicated with the grouting port.

[0023] Specifically, by fixing two symmetric mold parts on the left and right, the two mold parts jointly form the first end cap groove, the second end cap groove, the test mold cavity, the grouting port and the slurry containing groove. The test mold cavity is a cavity structure with an accommodation space through the first end cap installed on the first end cap groove and the second end cap installed on the second end cap groove. The prepared cement slurry is injected into the test mold cavity through the grouting port and overflows to a certain depth in the slurry containing groove. The cement slurry in the slurry containing groove can supplement the cement slurry in the test mold cavity and reduce the shrinkage rate of the cement stone. The curing mold for the compressive strength of the well cement stone can be placed in the autoclave of the high-temperature and high-pressure thickening instrument for curing. The highest working temperature of the high-temperature and high-pressure thickening instrument is 315 °C, and the highest working pressure is 275 MPa. Therefore, the curing mold can carry out curing tests under the well cementing design conditions (temperature < 315 °C, pressure < 275 MPa) in the autoclave of the high-temperature and high-pressure thickening instrument to simulate the compressive strength of the cement slurry cured under the well cementing design pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0025] Figure 1 It is a schematic structural diagram of the mold body provided by the embodiment of the present utility model;

[0026] Figure 2 It is a partial cross-sectional view of the mold body provided by the embodiment of the present utility model;

[0027] Figure 3 For Figure 1 The left half-sectional view;

[0028] Figure 4 For Figure 1 The top view;

[0029] Figure 5 For Figure 1 The bottom view.

[0030] Wherein:

[0031] 1 - Mold part, 11 - Connecting part;

[0032] 2 - Mold body, 21 - First end - cover groove, 22 - Fitting surface, 23 - Trial - mold cavity, 24 - Grouting port, 25 - Slurry - containing groove, 26 - Top surface, 27 - First protrusion, 271 - First abutting surface, 272 - Outer circumferential surface, 273 - Inner circumferential surface, 274 - Second groove, 28 - Bottom surface, 29 - Second protrusion, 291 - Second abutting surface, 292 - Second circumferential surface, 293 - Third groove;

[0033] 3 - First end - cover, 31 - Handle;

[0034] 4 - Second end - cover. Detailed implementation manners

[0035] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments in the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the protection scope of the present utility model.

[0036] In order to enable those skilled in the art of this technology to better understand the solution of the present utility model, the present utility model will be further described in detail below in conjunction with the accompanying drawings and specific implementation manners.

[0037] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the indicated position or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation of the present utility model.

[0038] The purpose of the present utility model is to provide a curing mold for the compressive strength of cement stone, which is applicable to the autoclave of high - temperature and high - pressure thickening instrument to simulate the compressive strength of cement slurry cured under the designed pressure of well cementing.

[0039] Please refer to Figure 1 、 Figure 2 and Figure 3, To achieve the above object, the utility model provides a curing mold for the compressive strength of cement stone, which includes a mold body 2 formed by enclosing two symmetric mold parts 1 on the left and right. The mold body 2 is provided with a first end cap groove 21 for installing the first end cap 3, a second end cap groove for installing the second end cap 4, a test mold cavity 23 located between the first end cap 3 and the second end cap 4 and having an accommodating space, a grouting port 24 communicated with the test mold cavity 23 and located at the top of the mold body 2, and a slurry containing groove 25 communicated with the grouting port 24.

[0040] Both of the two mold parts 1 are provided with a plurality of connecting holes. Preferably, there are two symmetric internal thread connecting holes on the upper and lower sides of the two mold parts 1 respectively, and the corresponding connecting holes are axially aligned. The connecting piece 11 can pass through the corresponding connecting holes to fixedly connect the two mold parts 1.

[0041] Among them, the two mold parts 1 are each half of the left and right sides of a hollow cylinder. Both of the two mold parts 1 are internally provided with a half of the first end cap groove 21, a half of the second end cap groove, and a half of the test mold cavity 23. The half of the test mold cavity 23 is a semi-cylindrical groove penetrating the mold part 1. The first end cap groove 21 and the second end cap groove are both groove structures further opened on the arc surface of the semi-cylindrical groove. By installing the first end cap 3 in the first end cap groove 21 and the second end cap 4 in the second end cap groove, the two ends of the test mold cavity 23 are sealed, so that the test mold cavity 23 is a cavity structure with an accommodating space. The outer shape of the test mold cavity 23 is a cylindrical structure, and the axis of the cylindrical structure is perpendicular to the axis of the mold body 2. There is a half of the grouting port 24 and a half of the slurry containing groove 25 in the shape of an inverted frustum at the top of both of the two mold parts 1. There is a fitting surface 22 on the side where the two mold parts 1 face each other. When the two mold parts 1 enclose to form the mold body 2, the two fitting surfaces 22 are closely fitted (install the first end cap 3 and the second end cap 4 to the designated positions before the two mold parts 1 enclose).

[0042] It should be noted that the outer shapes of the first end cap groove 21 and the second end cap groove can be the same, and they are only distinguished by naming. The outer shapes of the first end cap 3 and the second end cap 4 need to adapt to the first end cap groove 21 and the second end cap groove to achieve the sealing performance and prevent the cement slurry in the test mold cavity 23 from flowing out along the first end cap groove 21 and the second end cap groove.

[0043] By fixing two symmetric die pieces 1 on the left and right, the two die pieces 1 together form a first end cap groove 21, a second end cap groove, a test die cavity 23, a grouting port 24, and a slurry holding groove 25. The test die cavity 23 is a cavity structure with a containing space by installing a first end cap 3 on the first end cap groove 21 and a second end cap 4 on the second end cap groove. The prepared cement slurry is injected into the test die cavity through the grouting port 24 and overflows to a certain depth in the slurry holding groove 25. The cement slurry in the slurry holding groove 25 can supplement the cement slurry in the test die cavity to reduce the shrinkage rate of the cement stone. The curing mold for the compressive strength of the well cement stone can be placed in the autoclave of the high-temperature and high-pressure thickening instrument for curing. The maximum working temperature of the high-temperature and high-pressure thickening instrument is 315 °C, and the maximum working pressure is 275 MPa. Therefore, the curing mold can conduct curing tests under the well cementing design conditions (temperature < 315 °C, pressure < 275 MPa) in the autoclave of the high-temperature and high-pressure thickening instrument to simulate the compressive strength of the cement slurry cured under the well cementing design pressure.

[0044] For the convenience of understanding the following text, the features of the mold body 2 formed by enclosing the two die pieces 1 are introduced. In fact, each of the two die pieces 1 has half of the features related to the mold body 2.

[0045] Please refer to Figure 4 , in this embodiment, the top of the mold body 2 includes a top surface 26, and a first protrusion 27 is provided on the top surface 26. The middle of the first protrusion 27 is recessed inward to form the above-mentioned slurry holding groove 25. The slurry holding groove 25 is an inverted frustum-shaped groove, and the bottom of the slurry holding groove 25 is communicated with the top of the grouting port 24, so that when there is a containing space in the grouting port 24, the cement slurry at the bottom of the slurry holding groove 25 can all flow into the grouting port 24 to avoid the phenomenon that when the top of the grouting port 24 is higher than the bottom of the slurry holding groove 25, the cement slurry at the bottom of the slurry holding groove 25 cannot flow into the grouting port 24. Preferably, the cement slurry overflows to half of the depth of the slurry holding groove 25.

[0046] Among them, the first protrusion 27 includes a first abutting surface 271, an outer circumferential surface 272, and an inner circumferential surface 273. The first abutting surface 271 is parallel to the top surface 26 and is at a height higher than the top surface 26; the outer circumferential surface 272 is connected to the top surface 26 and the first abutting surface 271; the inner circumferential surface 273 is connected to the first abutting surface 271, and the end of the inner circumferential surface 273 facing away from the first abutting surface 271 is at a height lower than the top surface 26, which is convenient for the slurry holding groove 25 to hold a certain amount of cement slurry, which can supplement the cement slurry in the test die cavity and reduce the shrinkage rate of the cement stone.

[0047] Please refer to Figure 5, in this embodiment, considering that multiple mold bodies 2 need to be stacked vertically in a high-temperature and high-pressure thickening instrument kettle for curing, the cross-section of the outer circumferential surface 272 perpendicular to the axis of the mold body 2 is circular, and the diameter of the circle gradually increases from the first abutting surface 271 to the top surface 26; the bottom of the mold body 2 includes a bottom surface 28 parallel to the top surface 26, and a second protrusion 29 is provided on the bottom surface 28. The second protrusion 29 includes a second abutting surface 291 parallel to the bottom surface 28 and two second circumferential surfaces 292 connecting the second abutting surface 291 and the bottom surface 28. The distance between the first abutting surface 271 and the top surface 26 is equal to the distance between the second abutting surface 291 and the bottom surface 28. The second abutting surface 291 is a ring, and the inner diameter of the ring is greater than or equal to the diameter of the largest circle in the outer circumferential surface 272, so that the first protrusion 27 and the second protrusion 29 on the opposite sides of two adjacent upper and lower mold bodies 2 can fit together. Among them, the first abutting surface 271 of the lower mold body 2 abuts against the bottom surface 28 of the upper mold body 2, the second abutting surface 291 of the upper mold body 2 abuts against the top surface 26 of the lower mold body 2, and the inner second circumferential surface 292 of the upper mold body 2 can fit with the outer circumferential surface 272 of the lower mold body 2, so that two adjacent upper and lower mold bodies 2 can be stacked stably.

[0048] In addition, a through-type second groove 274 is also provided on the first protrusion 27, and the second groove 274 communicates with the slurry-containing groove 25. The height of the bottom of the second groove 274 is higher than or equal to the height of the top surface 26. A through-type third groove 293 is also provided on the second protrusion 29. During the curing process of the cement stone compressive strength mold, pressure can be transmitted to the cement slurry in the test mold cavity 23 through the second groove 274. The third groove 293 is used to ensure that the second groove 274 is always in communication with the outside (each of the two mold parts 1 has half of the second groove 274 and the third groove 293). For the convenience of the cement slurry pouring process, the cross-section of the grouting port 24 perpendicular to the axis of the mold body 2 is set as a rectangle, and each of the two mold parts 1 has half of the grouting port 24.

[0049] In some embodiments, considering the sealing effect of the first end cover 3 and the second end cover 4, both the first end cover 3 and the second end cover 4 include a first cylinder whose circumferential surface abuts against the first end cover groove 21 or the second end cover groove, a second cylinder provided on the side of the first cylinder facing away from the test mold cavity 23, and a handle 31 provided in the middle of the second cylinder on the side of the second cylinder facing away from the first cylinder. Among them, the diameter of the second cylinder is smaller than that of the first cylinder, and the circumferential surface of the second cylinder abuts against the mold part 1.

[0050] In addition, this cement stone compressive strength curing mold for well cementing can also be placed in a curing kettle and a water bath for curing the cement stone compressive strength.

[0051] It should be noted that in this specification, relational terms such as first and second are only used to distinguish one entity from several other entities, and do not necessarily require or imply any actual relationship or order between these entities.

[0052] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other.

[0053] Specific examples are used in this article to elaborate on the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. A curing mold for the compressive strength of hardened cement paste, characterized in that, The invention comprises a mold body (2) formed by two left-right symmetrical mold parts (1), the mold body (2) being provided with a first end cover groove (21) for installing a first end cover (3), a second end cover groove for installing a second end cover (4), a trial mold cavity (23) located between the first end cover (3) and the second end cover (4) and having a containing space, a grouting port (24) connected to the trial mold cavity (23) and located at the top of the mold body (2), and a grouting groove (25) connected to the grouting port (24).

2. The cement stone compressive strength curing mold according to claim 1, characterized in that, The top of the mold body (2) comprises a top surface (26), and a first protrusion (27) is provided on the top surface (26). The middle of the first protrusion (27) is recessed inwards to form the slurry containing groove (25). The slurry containing groove (25) is an inverted truncated cone-shaped groove, and the bottom of the slurry containing groove (25) is connected to the top of the grouting port (24).

3. The curing mold for the compressive strength of hardened cement paste according to claim 2, wherein The first protrusion (27) comprises: A first abutting surface (271) parallel to the top surface (26) and located at a height higher than the top surface (26); An outer circumferential surface (272) connected to the top surface (26) and the first abutting surface (271); The inner circumferential surface (273) is connected to the first abutting surface (271), and the height of an end of the inner circumferential surface (273) that is away from the first abutting surface (271) is lower than the top surface (26).

4. The cement stone compressive strength curing mold according to claim 3, characterized in that, The first protrusion (27) is further provided with a through-type second groove (274), and the second groove (274) is connected to the slurry containing groove (25), and the bottom of the second groove (274) is located at a height higher than or equal to the height of the top surface (26).

5. The curing mold for the compressive strength of hardened cement paste according to claim 3, wherein The cross-section of the outer circumferential surface (272) perpendicular to the axial direction of the mold body (2) is circular, and the diameter of the circle gradually increases along the direction from the first abutting surface (271) to the top surface (26); The bottom of the mold body (2) includes a bottom surface (28) parallel to the top surface (26), and a second protrusion (29) is provided on the bottom surface (28). The second protrusion (29) includes a second abutting surface (291) parallel to the bottom surface (28), and two second circumferential surfaces (292) connected to the second abutting surface (291) and the bottom surface (28). The distance between the first abutting surface (271) and the top surface (26) is equal to the distance between the second abutting surface (291) and the bottom surface (28). The second abutting surface (291) is a circular ring, and the inner diameter of the circular ring is greater than or equal to the diameter of the largest circle in the outer circumferential surface (272), so that the first protrusion (27) and the second protrusion (29) on the opposite side of two adjacent mold bodies (2) can fit together.

6. The cement stone compressive strength curing mold according to claim 1, characterized in that, The cross section of the grouting port (24) perpendicular to the axis of the mold body (2) is rectangular.

7. The curing mold for the compressive strength of hardened cement paste according to claim 1, characterized in that The first end cover (3) and the second end cover (4) both comprise: A first cylinder, a circumferential surface of which abuts against the first end cover groove (21) or the second end cover groove; A second cylinder is disposed on a side of the first cylinder away from the test mold cavity (23). The diameter of the second cylinder is smaller than that of the first cylinder, and the circumferential surface of the second cylinder abuts against the mold member (1). A handle (31) is disposed on a side of the second cylinder away from the first cylinder and is located at the middle of the second cylinder.

8. The curing mold for the compressive strength of hardened cement paste according to claim 1, characterized in that, Each of the two mold members (1) is provided with a plurality of connection holes, and the corresponding connection holes are axially aligned. A connecting member (11) can pass through the corresponding connection holes to fixedly connect the two mold members (1).

9. The cement stone compressive strength curing mold according to claim 1, characterized in that, The outer shape of the test mold cavity (23) is a cylindrical structure, and the axis of the cylindrical structure is perpendicular to the axis of the mold body (2).

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