Raw material proportioning process and equipment for low-density oil well cement production

Abstract

The invention relates to the field of cement production, in particular to a raw material proportioning process and equipment for low-density oil well cement production.The proportioning equipment comprises a feeding frame, storage bins, a proportioning barrel and a stirring box, the storage bins are evenly installed at the top end of the feeding frame, and the bottom end of the feeding frame is fixedly connected with the stirring box through a supporting frame; the proportioning barrel is arranged between the bottom of the feeding frame and the top of the stirring box, a fixed material disc is fixedly arranged in the feeding frame, a plurality of discharging cavities are evenly formed in the bottom of the fixed material disc, feeding ports in one-to-one correspondence with the discharging cavities are formed in the upper end of the fixed material disc, and different numbers of feeding holes are formed in the feeding ports in a penetrating mode according to the proportion of each raw material. And a first feeding plate is rotationally mounted in the fixed charging tray. According to the invention, the blanking amount of each raw material and the proportion of each raw material can be accurately detected by using the distance change and the change difference value, the accurate proportioning process of different raw materials is realized, and the proportioning efficiency and the proportioning precision are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of cement production, and particularly to a raw material proportioning process and equipment for the production of low-density oil well cement. Background Art

[0002] Oil well cement is specifically used for the cementing work of oil wells and gas wells, also known as plugging cement. Its main function is to cement and seal the casing with the surrounding rock formations, isolate the oil, gas, and water layers in the formation to prevent cross-interference, so as to form a good oil flow channel that flows from the oil layer to the ground and is well isolated in the well. Oil well cement is a special type of cement, which is made by grinding Portland cement clinker mainly composed of hydraulic calcium silicate, adding appropriate amount of gypsum and grinding aids.

[0003] During the production process of oil well cement, it is necessary to strictly proportion the raw materials according to the proportion components of each raw material. Most of the current proportioning methods are to manually weigh the specified weight of raw materials using weighing equipment, and then add all the raw materials into the mixing tank for mixing. However, when weighing and proportioning, it is impossible to precisely control the feeding amount of each raw material, and it is also impossible to calibrate the weight proportion of the raw materials after weighing, so the proportioning accuracy still needs to be improved. Summary of the Invention

[0004] The purpose of the present invention is to provide a raw material proportioning process and equipment for the production of low-density oil well cement, aiming to solve the above technical problems.

[0005] The purpose of the present invention can be achieved through the following technical solutions: A raw material proportioning equipment for the production of low-density oil well cement, including a feeding rack, a storage bin, a proportioning cylinder, and a mixing tank. The storage bins are evenly installed at the top of the feeding rack. The bottom of the feeding rack is fixedly connected to the mixing tank through a support frame. The proportioning cylinder is arranged between the bottom of the feeding rack and the top of the mixing tank. A fixed material tray is fixedly arranged inside the feeding rack. A number of feeding cavities are evenly arranged at the bottom of the fixed material tray. Feeding ports corresponding to the feeding cavities one by one are arranged at the upper end of the fixed material tray. Different numbers of feeding holes are penetrated through the feeding ports according to the proportion of each raw material. A first feeding plate is rotatably installed inside the fixed material tray, and a second feeding plate is rotatably installed inside the first feeding plate. The first feeding plate is used to control the feeding of all feeding ports simultaneously, and the second feeding plate is used to feed a single feeding port separately.

[0006] The inside of the proportioning cylinder is evenly divided into a number of quantitative cavities by partitions. The quantitative cavities are communicated with the corresponding feeding cavities through feeding pipes. A sliding baffle is hermetically and slidably installed inside the quantitative cavity. The bottom of the sliding baffle is fixedly connected to a discharge pipe. The bottom of the discharge pipe slidably penetrates through the proportioning cylinder and extends into the mixing tank. A displacement sensor is fixedly arranged at the bottom of the discharge pipe. Inductive pads corresponding to the displacement sensors one by one are fixedly arranged at the bottom of the proportioning cylinder.

[0007] As a further solution of the present invention: a return spring is provided between the bottom of the sliding baffle and the proportioning cylinder, an electric valve for controlling the opening and closing of the discharge pipe is provided at the upper end of the sliding baffle, and the displacement sensor is communicatively connected to the corresponding electric valve.

[0008] As a further solution of the present invention: a first motor is fixedly provided at the center of the upper end of the feeding rack, the output end of the first motor is fixedly connected to the first feeding plate, a plurality of first feeding holes are uniformly penetrated through the first feeding plate, and the first feeding holes are arranged in one-to-one correspondence with the feeding ports.

[0009] As a further solution of the present invention: an activity cavity is arranged inside the first feeding plate, a pivot shaft is fixedly provided at the center of the activity cavity, the second feeding plate is rotatably installed in the activity cavity, the pivot shaft is rotationally matched with the center of the second feeding plate, a synchronous gear is provided at the upper end of the second feeding plate, a second motor is fixedly provided at the upper end of the first feeding plate, a driving gear is connected to the output end of the second motor, and the driving gear is meshed with the synchronous gear.

[0010] As a further solution of the present invention: a plurality of discharging parts are uniformly penetrated through the second feeding plate, a blocking part is formed between two adjacent discharging parts, the discharging part is used for opening and communicating the first feeding holes, the blocking part is used for blocking and closing the first feeding holes, and a second feeding hole is penetrated through one of the blocking parts.

[0011] As a further solution of the present invention: an avoidance opening is provided at the upper end of the fixed material tray, and the second motor rotates in the avoidance opening along with the first feeding plate.

[0012] As a further solution of the present invention: a stirring motor is fixedly provided at the bottom of the stirring tank, a stirring shaft is connected to the output end of the stirring motor, a plurality of stirring rods are uniformly arranged on the side wall of the stirring shaft, and stirring fan blades are arranged at intervals along the axial direction on the outer wall of the stirring rod.

[0013] As a further solution of the present invention: one end of the stirring rod is rotationally matched with the stirring shaft through a rotating shaft, induction magnetic blocks are fixedly provided on the upper and lower two sides of the other end of the stirring rod, and the magnetic poles of the two induction magnetic blocks are opposite.

[0014] As a further solution of the present invention: a plurality of driving seats are uniformly arranged at equal intervals on the inner wall of the stirring tank, the induction magnetic blocks pass through the driving seats, driving magnetic blocks are fixedly provided at the upper and lower ends of the driving seats, the magnetic poles of the two driving magnetic blocks are opposite, and the magnetic poles of the driving magnetic blocks at the upper and lower ends of adjacent two driving seats are also opposite.

[0015] The present invention also provides a raw material proportioning process for the production of low-density oil well cement. Using the above-mentioned raw material proportioning equipment for the production of low-density oil well cement, it includes the following steps: Step 1: Prepare raw materials. According to the different numbers of feeding holes in each feeding port, add the corresponding proportion of raw materials into different storage bins according to the raw material ratio, and start preparing for feeding.

[0016] Step 2: Preliminary feeding and proportioning. Control the rotation of the first feeding plate to open all the feeding holes. Different raw materials enter the metering chamber through the feeding pipes respectively and press down the sliding baffle. Monitor the change in the distance between the displacement sensor and the induction pad, so as to accurately detect the feeding amount of each raw material and the proportion of each raw material.

[0017] Step 3: Fine-tune the proportion. According to the detected proportion between raw materials, when a certain raw material is lacking, control the rotation of the second feeding plate to make this raw material feed separately until it reaches the proportion component.

[0018] Step 4: Discharge and stir. The proportioned raw materials are fed into the stirring tank through the discharge pipe and are fully stirred and mixed in the stirring tank.

[0019] Advantages of the present invention: (1) By setting the fixed tray, the first feeding plate and the second feeding plate, since the ratio of the number of feeding holes in different feeding ports corresponds to the ratio of different raw materials, when feeding, add the corresponding proportion of raw materials into different storage bins. When controlling the rotation of the first feeding plate to start feeding simultaneously, the feeding rate of different raw materials through the feeding holes will also be proportional to the proportion of each raw material. Thus, the feeding amount of each raw material can be initially controlled by controlling the feeding speed, and the feeding time of each raw material entering the metering chamber is kept consistent, which is beneficial to the accurate proportioning of raw materials.

[0020] (2) By setting the proportioning cylinder, when the raw material enters the inside of the metering chamber, the sliding baffle will carry the raw material, and the sliding baffle will press down the discharge pipe to make it slide down. Use the displacement sensor to monitor the change in the distance between the displacement sensor and the induction pad in real time. The detected displacement distances of raw materials with different weight ratios will also form corresponding ratios. Thus, the feeding amount of each raw material and the proportion of each raw material can be accurately detected by using the distance change and the change difference. When a certain raw material is lacking, control the rotation of the second feeding plate to make this raw material feed separately until it reaches the specified proportion, realizing the accurate proportioning process of different raw materials, and effectively improving the proportioning efficiency and proportioning accuracy.

[0021] (3)When the proportioned raw materials enter the mixing box, the mixing motor starts, driving the mixing rod to rotate circumferentially through the mixing shaft. During this process, the induction magnetic block at the end of the mixing rod will pass through the driving seat. Using the repulsion of like magnetic poles and the attraction of opposite magnetic poles, the mixing rod will flip within the driving seat. When it continues to pass through the next driving seat, since the magnetic poles of the driving magnetic blocks at the upper and lower ends of adjacent driving seats are opposite, it can drive the mixing rod to flip again. As the mixing rod continuously rotates horizontally, it will achieve a flip around the axis every time it passes through a driving seat, so that the mixing rod can continuously rotate around its own axis while revolving around the axis. Coupled with the mixing fan blades, it will greatly improve the mixing effect of the raw materials, enabling the raw materials to be fully and evenly mixed. Description of the Drawings

[0022] The present invention will be further described below in conjunction with the drawings.

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0024] Figure 2 It is a schematic diagram of the bottom structure of the feeding rack in the present invention.

[0025] Figure 3 It is a schematic diagram of the internal structure of the feeding rack in the present invention.

[0026] Figure 4 It is a schematic diagram of the structure of the fixed material tray in the present invention.

[0027] Figure 5 It is a schematic diagram of the structure of the first feeding plate in the present invention.

[0028] Figure 6 It is a schematic diagram of the structure of the second feeding plate in the present invention.

[0029] Figure 7 It is a schematic diagram of the structure of the proportioning cylinder in the present invention.

[0030] Figure 8 It is a schematic diagram of the internal structure of the proportioning cylinder in the present invention.

[0031] Figure 9 It is a schematic diagram of the internal structure of the mixing box in the present invention.

[0032] Figure 10 It is a schematic diagram of the structure of the mixing rod in the present invention.

[0033] In the figure: 1. Loading rack; 11. Support frame; 12. Fixed material tray; 121. Lowering cavity; 122. Feeding port; 123. Feeding hole; 124. Avoidance port; 13. First loading plate; 131. Activity cavity; 132. Pivot; 133. First lowering hole; 14. Second loading plate; 141. Synchronous gear; 142. Discharge part; 143. Blocking part; 144. Second lowering hole; 15. First motor; 16. Second motor; 161. Driving gear; 2. Storage bin; 3. Mixing cylinder; 31. Partition board; 32. Quantitative cavity; 321. Lowering pipe; 33. Sliding baffle; 331. Return spring; 332. Electric valve; 34. Discharge pipe; 341. Displacement sensor; 342. Inductive pad; 4. Stirring tank; 41. Stirring motor; 42. Stirring shaft; 43. Stirring rod; 431. Stirring fan blade; 432. Rotating shaft; 433. Inductive magnetic block; 44. Driving seat; 441. Driving magnetic block. Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0035] Please refer to Figures 1-4 As shown in the figure, the present invention is a raw material proportioning device for the production of low-density oil well cement, including a loading rack 1, a storage bin 2, a mixing cylinder 3 and a stirring tank 4. The storage bin 2 is evenly installed at the top of the loading rack 1. The bottom of the loading rack 1 is fixedly connected to the stirring tank 4 through a support frame 11. The mixing cylinder 3 is arranged between the bottom of the loading rack 1 and the top of the stirring tank 4. A fixed material tray 12 is fixedly arranged in the loading rack 1. A plurality of lowering cavities 121 are evenly arranged at the bottom of the fixed material tray 12. Feeding ports 122 corresponding to the lowering cavities 121 one by one are arranged at the upper end of the fixed material tray 12. Different numbers of feeding holes 123 are arranged through the feeding ports 122 according to the proportion of each raw material. A first loading plate 13 is rotatably installed in the fixed material tray 12. A second loading plate 14 is rotatably installed in the first loading plate 13. The first loading plate 13 is used to control the simultaneous feeding of all the feeding ports 122, and the second loading plate 14 is used for the individual feeding of a single feeding port 122.

[0036] Specifically, by setting the fixed tray 12, the first feeding plate 13, and the second feeding plate 14, since the ratio of the number of feeding holes 123 in different feeding ports 122 corresponds to the ratio of different raw materials, when feeding, raw materials with corresponding proportions are added into different storage bins 2. When controlling the first feeding plate 13 to rotate to start feeding simultaneously, the feeding rate of different raw materials through the feeding holes 123 will also be proportional to the proportion of each raw material. Thus, the feeding amount of each raw material can be initially controlled by controlling the feeding speed, and the feeding time for each raw material to enter the metering chamber 32 is kept consistent, which is beneficial to the precise proportioning of raw materials.

[0037] As Figure 7 and Figure 8 shown, the inside of the proportioning cylinder 3 is evenly divided into several metering chambers 32 by a partition plate 31. The metering chambers 32 are communicated with the corresponding discharging chambers 121 through discharging pipes 321. A sliding baffle 33 is hermetically and slidably installed in the metering chamber 32. The bottom of the sliding baffle 33 is fixedly connected with a discharging pipe 34. The bottom of the discharging pipe 34 slidably penetrates through the proportioning cylinder 3 and extends into the mixing tank 4. A displacement sensor 341 is fixedly arranged at the bottom end of the discharging pipe 34. An induction pad 342 corresponding to the displacement sensor 341 is fixedly arranged at the bottom of the proportioning cylinder 3.

[0038] Specifically, by setting the proportioning cylinder 3, when the raw material enters the inside of the metering chamber 32, the sliding baffle 33 will carry the raw material, and the sliding baffle 33 will press down the discharging pipe 34 to make it slide downward. The displacement sensor 341 is used to monitor the change in the distance from the induction pad 342 in real time. The detected displacement distances of raw materials with different weight ratios will also form corresponding ratios. Thus, the discharging amount of each raw material and the proportion of each raw material can be accurately detected by using the distance change and the change difference. When a certain raw material is lacking, the second feeding plate 14 is controlled to rotate to make the raw material feed alone until the specified proportion is reached, realizing the precise proportioning process of different raw materials, and effectively improving the proportioning efficiency and proportioning accuracy.

[0039] As Figure 1 and Figure 8 shown, a return spring 331 is arranged between the bottom of the sliding baffle 33 and the proportioning cylinder 3. An electric valve 332 for controlling the opening and closing of the discharging pipe 34 is arranged at the upper end of the sliding baffle 33. The displacement sensor 341 is communicatively connected with the corresponding electric valve 332.

[0040] Specifically, during the feeding process, the raw materials on the sliding baffle 33 continuously increase, causing the sliding baffle 33 to slide downward and compress the return spring 331. During this process, the electric valve 332 remains in the closed state to prevent raw material leakage. When the downward movement distance of all the discharge pipes 34 reaches the specified value, it indicates that all the raw materials have reached the specified feeding amount and the proportion of each raw material meets the mixing ratio standard. At this time, the displacement sensor 341 sends a control signal to the electric valve 332 to open it, and the raw materials in the metering chamber 32 will enter the mixing tank 4 through the discharge pipes 34.

[0041] It should be noted that after the feeding is completed, the sliding baffle 33 will slide upward and reset under the elastic force of the return spring 331. To ensure the accuracy of quantitative mixing, all the sliding baffles 33 should be kept on the same horizontal plane in the initial state. The displacement sensor 341 is used to monitor whether the initial distance from the induction pad 342 remains consistent, so as to detect and correct the initial position of the sliding baffle 33.

[0042] As Figure 3 、 Figure 4 and Figure 5 shown, a first motor 15 is fixedly arranged at the center of the upper end of the feeding rack 1. The output end of the first motor 15 is fixedly connected to the first feeding plate 13. A plurality of first discharging holes 133 are uniformly arranged through the first feeding plate 13, and the first discharging holes 133 are arranged in one-to-one correspondence with the feeding ports 122.

[0043] Specifically, when the first motor 15 is started, it drives the first feeding plate 13 to rotate until the first discharging holes 133 are aligned with the corresponding feeding ports 122. At this time, the raw materials in the feeding ports 122 can be communicated with the first discharging holes 133 through the feeding holes 123 to achieve the synchronous feeding process.

[0044] As Figure 3 、 Figure 5 and Figure 6 shown, an activity cavity 131 is arranged inside the first feeding plate 13. A pivot shaft 132 is fixedly arranged at the center of the activity cavity 131. The second feeding plate 14 is rotatably installed in the activity cavity 131. The pivot shaft 132 is rotationally matched with the center of the second feeding plate 14. A synchronous gear 141 is arranged at the upper end of the second feeding plate 14. A second motor 16 is fixedly arranged at the upper end of the first feeding plate 13. The output end of the second motor 16 is connected with a driving gear 161, and the driving gear 161 is meshed with the synchronous gear 141.

[0045] As Figure 5 and Figure 6As shown, a number of discharge parts 142 are evenly and penetratingly arranged on the second loading plate 14. A blocking part 143 is formed between two adjacent discharge parts. The discharge part 142 is used to open and connect the first discharge hole 133, and the blocking part 143 is used to block and close the first discharge hole 133. A second discharge hole 144 is penetratingly arranged on one of the blocking parts 143.

[0046] Specifically, when the first discharge hole 133 is discharging normally, at this time each discharge part 142 is aligned with the corresponding first discharge hole 133, so that the discharge hole is open and connected. When the second motor 16 drives the synchronous gear 141 to rotate through the driving gear 161, the synchronous gear 141 will drive the second loading plate 14 to rotate until the blocking part 143 blocks and closes the first discharge hole 133. At this time, the feed inlet 122 and the first discharge hole 133 still remain in a connected state, and the second discharge hole 144 will be connected to one of the first discharge holes 133, and the remaining first discharge holes 133 will be blocked by the blocking part 143, so as to realize the separate discharging process of a certain raw material.

[0047] As Figure 4 shown, an avoidance opening 124 is arranged at the upper end of the fixed material tray 12, and the second motor 16 rotates in the avoidance opening 124 along with the first loading plate 13.

[0048] Specifically, when the first loading plate 13 rotates inside relative to the fixed material tray 12, the avoidance opening 124 provides enough rotating space for the second motor 16, so that the second motor 16 can rotate freely along with the first loading plate 13.

[0049] As Figure 9 and Figure 10 shown, a stirring motor 41 is fixedly arranged at the bottom of the stirring tank 4. The output end of the stirring motor 41 is connected with a stirring shaft 42. A number of stirring rods 43 are evenly arranged on the side wall of the stirring shaft 42. Stirring fan blades 431 are arranged at intervals along the axial direction on the outer wall of the stirring rod 43.

[0050] Furthermore, one end of the stirring rod 43 is rotationally matched with the stirring shaft 42 through a rotating shaft 432. Induction magnetic blocks 433 are fixedly arranged on the upper and lower two sides of the other end of the stirring rod 43, and the magnetic poles of the two induction magnetic blocks 433 are opposite.

[0051] Even further, a number of driving seats 44 are evenly arranged at equal intervals on the inner wall of the stirring tank 4. The induction magnetic blocks 433 pass through the driving seats 44. Driving magnetic blocks 441 are fixedly arranged at the upper and lower ends of the driving seats 44. The magnetic poles of the two driving magnetic blocks 441 are opposite, and the magnetic poles of the driving magnetic blocks 441 at the upper and lower ends of adjacent two driving seats 44 are also opposite.

[0052] Specifically, when the proportioned raw materials enter the mixing box 4, the mixing motor 41 starts, driving the mixing rod 43 to rotate circumferentially through the mixing shaft 42. During this process, the induction magnetic block 433 at the end of the mixing rod 43 will pass through the driving seat 44. Utilizing the repulsion of like magnetic poles and the attraction of opposite magnetic poles, the mixing rod 43 will flip within the driving seat 44. When it continues to pass through the next driving seat 44, since the magnetic poles of the driving magnetic blocks 441 at the upper and lower ends of adjacent driving seats 44 are opposite, the mixing rod 43 can be driven to flip again. As the mixing rod 43 continuously rotates horizontally, it will achieve an axis-around flip every time it passes through a driving seat 44, enabling the mixing rod 43 to continuously rotate around its own axis while revolving around the axis. Together with the mixing fan blades 431, this will greatly improve the mixing effect of the raw materials, ensuring that all raw materials are fully and evenly mixed.

[0053] The working principle of the above device is as follows: As Figures 1-10 shown, when in use, first, according to the different numbers of feeding holes 123 on each feeding port 122, the corresponding proportion of raw materials is added to the different storage bins 2 according to the raw material ratio. The first motor 15 drives the first feeding plate 13 to rotate until the first discharging hole 133 is aligned with each corresponding feeding port 122, and feeding starts simultaneously. The feeding rate of different raw materials through the feeding holes 123 is also proportional to the proportion of each raw material. Thus, the feeding amount of each raw material can be initially controlled by controlling the feeding speed, and the feeding time for each raw material to enter the metering chamber 32 is kept consistent. When the raw materials enter the interior of the metering chamber 32, the sliding baffle 33 will carry the raw materials, and the sliding baffle 33 will press down the discharging pipe 34 to make it slide downward. The displacement sensor 341 is used to continuously monitor the change in the distance between it and the induction pad 342. The detected displacement distances of raw materials with different weight ratios will also form corresponding ratios. Therefore, the feeding amount of each raw material and the proportion of each raw material can be accurately detected by using the distance change and the change difference. When a certain raw material is lacking, the second motor 16 drives the synchronous gear 141 to rotate through the driving gear 161. The synchronous gear 141 will drive the second feeding plate 14 to rotate until the blocking portion 143 blocks and closes the first discharging hole 133. At this time, the feeding port 122 is still in communication with the first discharging hole 133, while the second discharging hole 144 will be in communication with one of the first discharging holes 133, and the remaining first discharging holes 133 will be blocked by the blocking portion 143, thus controlling the separate feeding of a certain raw material until the specified proportion is reached, realizing the precise proportioning process of different raw materials. When the proportioned raw materials enter the mixing box 4, the mixing motor 41 starts, and the mixing rod 43 can continuously rotate around its own axis while revolving around the axis. Together with the mixing fan blades 431, this will greatly improve the mixing effect of the raw materials, ensuring that all raw materials are fully and evenly mixed.

[0054] The present invention also provides a raw material proportioning process for the production of low-density oil well cement. Using the above-mentioned raw material proportioning equipment for the production of low-density oil well cement, it includes the following steps: Step 1: Prepare raw materials. According to the different numbers of feeding holes 123 on each feeding port 122, corresponding proportioned raw materials are respectively added into different storage bins 2 according to the raw material ratio, and start to prepare for feeding.

[0055] Step 2: Preliminary feeding and proportioning. Control the rotation of the first feeding plate 13 to open all the feeding holes 123. Different raw materials respectively enter the metering chamber 32 through the feeding pipes 321 and press down the sliding baffle 33. The displacement sensor 341 monitors the change in the distance between the induction pad 342, so as to accurately detect the feeding amount of each raw material and the proportion of each raw material.

[0056] Step 3: Fine-tune the proportion. According to the detected proportion between each raw material, when a certain raw material is lacking, control the rotation of the second feeding plate 14 to feed the raw material alone until the raw material reaches the proportion component.

[0057] Step 4: Discharge and stir. The proportioned raw materials are passed into the stirring tank 4 through the discharge pipe 34 and are fully stirred and mixed in the stirring tank 4.

[0058] It should be noted that the proportion of low-density oil well cement needs to be adjusted according to the specific application scenario, well depth and performance requirements. The following is a specific description: Low-density oil well cement is a special cement used for well cementing operations in oil, natural gas, etc. Its production raw materials are as follows: Cement clinker: It is mainly formed by high-temperature calcination of raw materials such as limestone, clay, iron ore and coal, and is the main cementitious component of cement; Mineral admixtures: Commonly used ones include fly ash, slag, silica fume, etc. They can reduce the density of cement and improve the performance of cement at the same time, such as increasing the later strength of cement stone and increasing the fluidity of cement slurry; Gypsum: Its main function is to adjust the setting time of cement. Generally, natural gypsum or industrial by-product gypsum is used.

[0059] Its raw material ratio is as follows: Cement clinker usually accounts for about 60%-80%, the dosage of mineral admixtures is generally 20% - 40%, among which fly ash can account for 30%-70% of the total amount of mineral admixtures, slag accounts for 20%-50%, silica fume accounts for 5%-15%, and the dosage of gypsum is generally 3%-5% of the cement quality.

[0060] The production of low-density oil well cement includes raw material preparation, raw meal preparation, clinker calcination, cement grinding and packaging. Each component of various raw materials is accurately metered according to the design formula and put into an efficient mixing equipment for full stirring and mixing to ensure the mixing uniformity. Among them, the raw materials are pretreated, proportioned and ground, homogenized and packaged, and finally the finished low-density oil well cement is made. During the whole production process, the product quality of each link needs to be strictly detected and controlled.

[0061] The above is the general situation of the production of low-density oil well cement. In actual production, the raw material ratio and production process may vary due to factors such as production manufacturers and product performance requirements.

[0062] The above has described in detail an embodiment of the present invention, but the content described is only a preferred embodiment of the present invention and cannot be considered as limiting the scope of implementation of the present invention. All equivalent changes and improvements made according to the scope of the application of the present invention should still fall within the scope covered by the patent of the present invention.

Claims

1. A raw material proportioning device for the production of low-density oil well cement, comprising a feeding rack (1), a storage bin (2), a proportioning cylinder (3) and a mixing tank (4), characterized in that, The storage bin (2) is evenly installed at the top of the feeding rack (1). The bottom end of the feeding rack (1) is fixedly connected to the mixing tank (4) through a support frame (11). The proportioning cylinder (3) is arranged between the bottom of the feeding rack (1) and the top of the mixing tank (4). A fixed material tray (12) is fixedly arranged inside the feeding rack (1). A number of feeding cavities (121) are evenly arranged at the bottom of the fixed material tray (12). Feeding ports (122) corresponding to the feeding cavities (121) one by one are arranged at the upper end of the fixed material tray (12). Different numbers of feeding holes (123) are arranged through the feeding ports (122) according to the proportion of each raw material. A first feeding plate (13) is rotatably installed inside the fixed material tray (12). A second feeding plate (14) is rotatably installed inside the first feeding plate (13). The first feeding plate (13) is used to control the feeding of all the feeding ports (122) simultaneously. The second feeding plate (14) is used to feed a single feeding port (122) separately; The inside of the proportioning cylinder (3) is evenly divided into a number of quantitative cavities (32) by a partition plate (31). The quantitative cavities (32) are communicated with the corresponding feeding cavities (121) through feeding pipes (321). A sliding baffle (33) is hermetically and slidably installed inside the quantitative cavity (32). A discharge pipe (34) is fixedly connected to the bottom of the sliding baffle (33). The bottom of the discharge pipe (34) slidably penetrates through the proportioning cylinder (3) and extends into the mixing tank (4). A displacement sensor (341) is fixedly arranged at the bottom end of the discharge pipe (34). Induction pads (342) corresponding to the displacement sensor (341) one by one are fixedly arranged at the bottom of the proportioning cylinder (3).

2. The raw material proportioning equipment for producing low-density oil well cement according to claim 1, characterized in that A return spring (331) is arranged between the bottom of the sliding baffle (33) and the proportioning cylinder (3). An electric valve (332) for controlling the opening and closing of the discharge pipe (34) is arranged at the upper end of the sliding baffle (33). The displacement sensor (341) is communicatively connected to the corresponding electric valve (332).

3. The raw material proportioning equipment for producing low-density oil well cement according to claim 1, characterized in that, A first motor (15) is fixedly arranged at the center of the upper end of the feeding rack (1). The output end of the first motor (15) is fixedly connected to the first feeding plate (13). First feeding holes (133) are evenly arranged through the first feeding plate (13). The first feeding holes (133) are arranged corresponding to the feeding ports (122) one by one.

4. A raw material proportioning device for producing low-density oil well cement according to claim 3, characterized in that, An activity cavity (131) is arranged inside the first feeding plate (13). A pivot shaft (132) is fixedly arranged at the center of the activity cavity (131). The second feeding plate (14) is rotatably installed inside the activity cavity (131). The pivot shaft (132) is rotationally matched with the center of the second feeding plate (14). A synchronous gear (141) is arranged at the upper end of the second feeding plate (14). A second motor (16) is fixedly arranged at the upper end of the first feeding plate (13). The output end of the second motor (16) is connected with a driving gear (161). The driving gear (161) is meshed with the synchronous gear (141).

5. A raw material proportioning device for producing low-density oil well cement according to claim 4, characterized in that, A plurality of discharge parts (142) are uniformly arranged through the second feeding plate (14). A blocking part (143) is formed between two adjacent discharge parts. The discharge part (142) is used to open and connect the first blanking hole (133), and the blocking part (143) is used to block and close the first blanking hole (133). A second blanking hole (144) is arranged through one of the blocking parts (143).

6. The raw material proportioning device for producing low-density well cement according to claim 4, characterized in that, An avoidance opening (124) is arranged at the upper end of the fixed material tray (12). The second motor (16) rotates in the avoidance opening (124) along with the first feeding plate (13).

7. A raw material proportioning device for producing low-density oil well cement according to claim 1, characterized in that, A stirring motor (41) is fixedly arranged at the bottom of the stirring tank (4). The output end of the stirring motor (41) is connected with a stirring shaft (42). A plurality of stirring rods (43) are uniformly arranged on the side wall of the stirring shaft (42). Stirring fan blades (431) are arranged at intervals along the axial direction on the outer wall of the stirring rod (43).

8. The raw material proportioning device for producing low-density oil well cement according to claim 7, characterized in that, One end of the stirring rod (43) is rotationally matched with the stirring shaft (42) through a rotating shaft (432). Induction magnets (433) are fixedly arranged on the upper and lower surfaces of the other end of the stirring rod (43). The magnetic poles of the two induction magnets (433) are opposite to each other.

9. A raw material proportioning device for producing low-density oil well cement according to claim 8, characterized in that, A plurality of driving seats (44) are uniformly arranged at equal intervals on the inner wall of the stirring tank (4). The induction magnet (433) passes through the driving seat (44). Driving magnets (441) are fixedly arranged at the upper and lower ends of the driving seat (44). The magnetic poles of the two driving magnets (441) are opposite to each other, and the magnetic poles of the driving magnets (441) at the upper and lower ends of two adjacent driving seats (44) are also opposite to each other.

10. A raw material proportioning process for producing low-density oil well cement, using a raw material proportioning device for producing low-density oil well cement as described in claim 1, characterized in that, Including the following steps: Step 1: Prepare raw materials. According to the different numbers of feeding holes (123) at each feeding port (122), add the corresponding proportion of raw materials into different storage bins (2) according to the raw material ratio, and start preparing for feeding. Step 2: Preliminary feeding ratio. Control the rotation of the first feeding plate (13) to open all the feeding holes (123). Different raw materials respectively enter the metering cavity (32) through the feeding pipes (321) and press down the sliding baffle (33). Monitor the change of the distance between the displacement sensor (341) and the induction cushion block (342), so as to accurately detect the feeding amount of each raw material and the ratio of each raw material. Step 3: Fine-tune the ratio. According to the detected ratio between the raw materials, when a certain raw material is lacking, control the rotation of the second feeding plate (14) to feed the raw material alone until the raw material reaches the proportion component. Step 4: Discharge and stir. The proportioned raw materials are introduced into the stirring tank (4) through the discharge pipe (34) and are fully stirred and mixed in the stirring tank (4).

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