Anode carbon block air permeability detection device and method

Abstract

The invention discloses an anode carbon block air permeability detection device and method, and relates to the technical field of anode carbon block detection.The anode carbon block air permeability detection device comprises a vacuum system, an air supply system and a sample detection body; the sample testing main body comprises a steering engine, a sleeve, a sealing rubber pipe fitting and a fixed piston connected to the supporting platform; the detection method of the anode carbon block air permeability detection device comprises sampling and sample pretreatment. Compared with an existing mode that only one sample can be placed and detected each time, the sample detection device has the advantages that a plurality of samples can be placed at the same time and detected in sequence; in other words, after all the samples are placed on the corresponding sample detection main bodies, the gas supply system controls all the sealing rubber pipe fittings to seal the side walls of all the samples at the same time, then all the samples are detected in sequence by switching all the electromagnetic on-off valves and utilizing the vacuum system, and after one batch of samples are detected, another batch of samples is replaced, so that the detection efficiency is greatly improved; and the labor intensity is reduced.

Description

Technical Field:

[0001] The present invention relates to the technical field of anode carbon block detection, and particularly relates to an anode carbon block air permeability detection device and method. Background Art:

[0002] The anode carbon block for aluminum electrolysis is made from petroleum coke as raw material and coal tar pitch as binder through processes such as petroleum coke calcination, medium crushing, screening, grinding, batching, kneading, forming, roasting, etc.; the quality of the anode carbon block is an important guarantee for the normal production of the electrolytic cell, and the judgment of the quality of the anode carbon block usually requires prior detection of various performance indicators of the anode carbon block, such as the detection of the ash content and air permeability of the anode carbon block, and the detection of harmful impurities such as sodium, vanadium, and iron contained in the anode carbon block.

[0003] For aluminum electrolysis enterprises, the performance indicators of the anode carbon block are a very important part, directly affecting the quality of aluminum. Therefore, the in-plant detection of the anode carbon blocks purchased by aluminum electrolysis enterprises is a very important link. Among them, air permeability is an important indicator reflecting the quality of the anode carbon block and has an important impact on the excessive consumption of the anode during the electrolysis process.

[0004] Currently, when detecting the air permeability of a batch of incoming anode carbon blocks, multiple blocks are sampled proportionally and multiple samples are intercepted from each block. Workers need to perform a large amount of work such as sample preparation, size measurement, and placing on the existing detection device for detection. Among them, during the detection, individual samples need to be placed on the existing detection device for sequential detection until all samples are detected and compared with the qualified standard (≤2 npm); in the existing detection method, in addition to the preliminary sample preparation and size measurement, the taking and placing and detection operations of each sample on the existing detection device in sequence will consume a large amount of time, resulting in low efficiency of the entire detection process and high manual labor intensity. Summary of the Invention:

[0005] The purpose of the present invention is to provide an anode carbon block air permeability detection device and method that are conducive to improving the detection efficiency and reducing the manual labor intensity.

[0006] The present invention is implemented by the following technical solutions: An air permeability detection device for anode carbon blocks, which includes a vacuum system, a gas supply system, and more than one set of sample testing bodies; The sample testing body includes a servo motor, a sleeve, a sealed rubber pipe fitting, and a fixed piston connected to a support platform. A blind hole is coaxially opened at the top end of the fixed piston. A vacuum channel is provided inside the fixed piston. The top end of the vacuum channel communicates with the blind hole, and the bottom end of the vacuum channel communicates with the vacuum system. A U-shaped tube manometer is connected to the vacuum system; The sleeve is slidably sleeved on the fixed piston, and a sliding pin is fixed on the outer wall of the sleeve; The servo motor is fixed on the support platform. The output shaft of the servo motor is connected to a driving arm, and a notch sleeving the sliding pin is opened on the driving arm; A groove is circumferentially opened on the inner wall of the sleeve, and the sealed rubber pipe fitting is embedded and installed in the groove. The air chamber of the sealed rubber pipe fitting communicates with the gas supply system.

[0007] Further, a porous filter paper is laid at the bottom of the blind hole, and a sponge rubber is plugged at the channel opening of the vacuum channel in the blind hole.

[0008] Further, the sealed rubber pipe fitting includes an annular cavity and more than one sealing rubber ring integrally formed with the inner side of the annular cavity. The sealing rubber ring communicates with the air chamber of the annular cavity.

[0009] Further, elastic retaining rings are clamped on the outer walls of the annular cavity on both sides of the sealing rubber ring.

[0010] Further, a horizontally arranged test platform is fixedly connected above the support platform. Through holes corresponding to each sample testing body are opened on the test platform, and the sleeve of the sample testing body movably passes through the corresponding through holes.

[0011] Further, a bracket is connected to the test platform, and a pressing mechanism is correspondingly connected to the bracket directly above each sample testing body; The pressing mechanism includes a top rod and a sleeve slidably sleeved on the top rod coaxially. The top end of the sleeve is fixedly connected to the bracket. The sleeve and the corresponding fixed sleeve are coaxial, and a spring abutting against the top end of the top rod is arranged inside the sleeve.

[0012] Further, the gas supply system includes an air pump, an electromagnetic reversing valve, and a gas supply pipeline. One end of the gas supply pipeline is sealed through the side wall of the sleeve and communicates with the air chamber of the annular cavity. The other end of the gas supply pipeline is connected to an interface of the electromagnetic reversing valve, and the air inlet and exhaust port of the air pump are correspondingly connected to two interfaces on the electromagnetic reversing valve.

[0013] Further, the vacuum system includes a vacuum pump, a vacuum tank, vacuum branch pipes, and a vacuum main pipe. The bottom end of the vacuum channel of each fixed piston is connected to one of the vacuum branch pipes. Each of the vacuum branch pipes is connected to one end of the vacuum main pipe. The other end of the vacuum main pipe is connected to one end of the U-tube manometer. The vacuum main pipe is connected to the inlet of the vacuum tank through a bypass pipe. The outlet of the vacuum tank is connected to the vacuum pump. An electromagnetic on-off valve is installed on the vacuum branch pipe, and an electromagnetic main valve is installed on the bypass pipe.

[0014] A method for detecting the air permeability of an anode carbon block includes sampling and sample pretreatment, and further includes the following steps:

[0015] (1) Lift each ejector rod through the connecting frame, and place a standard sample and each sample to be tested along the inner wall of the sleeve of the corresponding sample testing body on the fixed piston.

[0016] (2) Start the air pump to suck air from the air supply pipeline, causing the sealed rubber pipe fitting to retract.

[0017] (3) Start the servo motor. Under the cooperation of the notch and the sliding pin, the driving arm drives the sleeve to move upward to a high position.

[0018] (4) Release the connecting frame, so that the bottom end of the ejector rod contacts the center of the sample. Under the action of the spring, the bottom end of the sample fits tightly with the fixed piston.

[0019] (5) Switch the electromagnetic directional valve to the right working position. The air pump sucks air from the atmosphere and sends it into the sealed rubber pipe fitting through the air supply pipeline. The sealing rubber ring expands to seal the side wall of the sample.

[0020] (6) Open the electromagnetic main valve and one electromagnetic on-off valve corresponding to the standard sample. The vacuum pump evacuates the air. When the liquid level in the U-tube manometer reaches the position of sensor three, close the electromagnetic main valve. The air flow through the sample reduces the vacuum degree. When the liquid level in the U-tube manometer reaches sensor two, record the time at this moment. When the liquid level reaches sensor one, record the time at this moment again, and then calculate the time difference tc between the two times.

[0021] (7) After the liquid level in the U-tube manometer in step (6) returns to the equilibrium mark line position, close the corresponding electromagnetic on-off valve to complete the detection of the standard sample.

[0022] (8) Repeat steps (6) and (7) to detect the time differences ts of other samples in turn.

[0023] After the detection of each sample is completed, turn off the vacuum pump and the electromagnetic on-off valve; switch the electromagnetic directional valve to the left working position, and the air pump sucks air from the air supply pipeline to retract the sealed rubber pipe fitting, then turn off the air pump; lift each ejector rod upward, and the servo controls the sleeve to move downward to the low position, so that the upper parts of each sample are exposed, facilitating the removal of the samples and replacing them with the next batch of samples to be tested, and then repeat the above steps (1) to (8) for detection;

[0024] (10) Using the known air permeability Dc of the standard sample and the detected time difference tc, calculate the correction factor fc according to formula (1):

[0025]

[0026] In the formula, fc - correction factor, unit: cubic meter per second;

[0027] tc - time difference, unit: second;

[0028] Dc - air permeability of the standard sample, unit: 10 -9 square meter;

[0029] 1963 - cross-sectional area of the sample corresponding to a test sample diameter of 50 mm, unit: square millimeter;

[0030] 20 - height of the corresponding test sample, unit: millimeter.

[0031] (11) Calculate the air permeability Ds of the test sample according to formula (2):

[0032]

[0033] In the formula, Ds - air permeability of the test sample, unit: 10 -9 square meter;

[0034] ts - time difference, unit: second;

[0035] hs - average height of the sample, unit: millimeter;

[0036] A - cross-sectional area of the sample, unit: square millimeter

[0037] Furthermore, during sampling, a cylindrical sample is taken from a predetermined position on the anode carbon block using a hollow drill. The diameter of the sample is 50 mm and the length is 75 mm;

[0038] The sample pretreatment includes the following steps:

[0039] Step 1. Sample preparation: Cut off the ends to obtain a sample with a length of 20 mm and blow off the attachments on it;

[0040] Step 2: Drying: Dry at 110℃±5℃ for 12 hours;

[0041] Step 3: Measure the sample height: Use a caliper to measure the height of the cylindrical sample at 90° intervals along its circumference, with a deviation of no more than 0.02 mm. Calculate the average value hs of the height measurements.

[0042] Step 4. Measure the sample diameter: Use a caliper to measure two sets of diameter data, with an interval of 90° between the two sets. The deviation of each set should not exceed 0.02mm. Each set of diameter data should be measured four times, once at the upper and lower ends of the sample and twice at the middle point of the axis. Calculate the average value ds of the two sets of diameter measurements, and then calculate the cross-sectional area A of the sample.

[0043] Advantages of the present invention:

[0044] (1) Compared with the existing method of placing only one sample for testing at a time, the present invention can place multiple samples at the same time and test them in sequence; that is, after each sample is placed on the corresponding test sample body, the air supply system controls the sealing rubber tubes to seal the side walls of each sample at the same time, and then by switching the electromagnetic on-off valves, the vacuum system is used to test each sample in sequence. After one batch of samples is tested, it is replaced with another batch, which greatly improves the testing efficiency and reduces the labor intensity.

[0045] (2) The pressing mechanism can simultaneously press down each sample placed on the test platform, so that the bottom end of the sample fits tightly with the corresponding fixed piston without the need for staff assistance, thereby ensuring the efficiency and reliability of the test. Description of the drawings:

[0046] Figure 1 It is a structural schematic diagram of the present invention.

[0047] Figure 2 Schematic diagram of the structure of the gas supply system of the present invention.

[0048] Figure 3 This is a schematic structural diagram of the U-tube pressure gauge of the present invention.

[0049] Figure 4 It is a partially enlarged schematic diagram of the sample testing body of the present invention.

[0050] Figure 5 It is a partially enlarged schematic diagram of the sealing rubber tube according to the present invention.

[0051] Figure 6 This is a schematic diagram of the use state of the sleeve of the present invention when it is in the lowest position.

[0052] Figure 7 This is a schematic diagram of the usage state when the sleeve of the present invention is in the highest position.

[0053] Figure 8 This is a partially enlarged schematic view of the pressing mechanism of the present invention.

[0054] The markings of each component in the attached drawings are as follows: air pump 1, electromagnetic reversing valve 2, air supply pipeline 3, vacuum pump 4, vacuum tank 5, vacuum main pipe 6, vacuum branch pipe 7, U-shaped tube manometer 8, sensor one 8.1, sensor two 8.2, sensor three 8.3, bypass pipeline 9, electromagnetic on-off valve 10, electromagnetic main valve 11, sample measurement main body 12, servo motor 12.1, sleeve 12.2, groove 12.21, snap ring 12.22, sealed rubber pipe fitting 12.3, annular cavity 12.31, sealing rubber ring 12.32, elastic retaining ring 12.33, fixed piston 12.4, blind hole 12.41, vacuum channel 12.42, filter paper 12.5, sponge rubber 12.6, sliding pin 12.7, driving arm 12.8, notch 12.81, test platform 13, through hole 13.1, bracket 14, pressing mechanism 15, ejector rod 15.1, sleeve 15.2, spring 15.3, connecting frame 15.4, support platform 16. Specific embodiments:

[0055] 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.

[0056] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "top", "bottom", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the attached drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0057] Example 1: As Figures 1 to 3 shown, this embodiment provides an anode carbon block air permeability detection device, which includes a gas supply system, a vacuum system, and six groups of sample measurement main bodies 12.

[0058] The air supply system includes an air pump 1, an electromagnetic directional valve 2, and an air supply pipeline 3. One end of the air supply pipeline 3 is connected to an interface of the electromagnetic directional valve 2, and the air inlet and outlet of the air pump 1 are correspondingly connected to two interfaces on the electromagnetic directional valve 2. A two-position four-way electromagnetic directional valve 2 is used. When switched to the left working position, the air pump 1 sucks air from the air supply pipeline 3 and then releases it into the atmosphere. When switched to the right working position, the air pump 1 sucks air from the atmosphere and then sends it into the air supply pipeline 3. The left working position is the initial working state of the electromagnetic directional valve 2.

[0059] The vacuum system includes a vacuum pump 4, a vacuum tank 5, vacuum branch pipes 7, and a vacuum main pipe 6. Each vacuum branch pipe 7 is connected to one end of the vacuum main pipe 6. The other end of the vacuum main pipe 6 is connected to one end of a U-shaped tube manometer 8. The vacuum main pipe 6 is connected to the inlet of the vacuum tank 5 through a bypass pipeline 9. The outlet of the vacuum tank 5 is connected to the vacuum pump 4. An electromagnetic on-off valve 10 is installed on the vacuum branch pipe 7, and an electromagnetic main valve 11 is installed on the bypass pipeline 9. The electromagnetic on-off valve 10 and the electromagnetic main valve 11 are opened before the vacuum pump 4 is started, and the vacuum tank 5 plays a role in stabilizing the pressure. Among them, the U-shaped tube manometer 8 is externally equipped with three fork-shaped optical sensors. The lowest sensor three 8.3 is installed at a position 145 mm below the balance mark line, and the other two sensors are installed at positions 30 mm (sensor one 8.1) and 80 mm (sensor two 8.2) below the balance mark line respectively. Each sensor is electrically connected to the input end of the controller, and the output end of the controller is connected to a buzzer alarm for prompting the recording time; or purchase an existing controller that can automatically record time and calculate the time difference.

[0060] As Figures 4 to 7 shown, each sample measurement main body 12 includes a servo motor 12.1, a sleeve 12.2, a sealed rubber pipe fitting 12.3, and a fixed piston 12.4 connected to a support platform 16. A blind hole 12.41 is coaxially opened at the top end of the fixed piston 12.4. A vacuum channel 12.42 is provided inside the fixed piston 12.4. The top end of the vacuum channel 12.42 communicates with the blind hole 12.41. The top end of the fixed piston 12.4 is used to place the anode carbon block sample to be measured. The diameter of the fixed piston 12.4 is the same as the diameter of the anode carbon block. The bottom end of the vacuum channel 12.42 is connected to a vacuum branch pipe 7. A porous filter paper 12.5 is laid at the bottom of the blind hole 12.41. A sponge rubber 12.6 is plugged at the channel opening of the vacuum channel 12.42 in the blind hole 12.41, which allows air to pass through while blocking dust. The porous filter paper 12.5 and the sponge rubber 12.6 play a protective role for the vacuum pump 4 to prevent dust or sample particles from entering the vacuum pump 4 and causing damage.

[0061] The sleeve 12.2 is slidably mounted on the fixed piston 12.4, and a sliding pin 12.7 is fixed to the outer wall of the sleeve 12.2; a servo 12.1 is fixed to the support platform 16, and an output shaft of the servo 12.1 is connected to a driving arm 12.8, and a notch 12.81 is formed on the driving arm 12.8 and is sleeved on the sliding pin 12.7; when the sliding pin 12.7 is placed at one end of the notch 12.81, the sleeve 12.2 is in the lowest position, and the distance between the top end of the sleeve 12.2 and the top end of the fixed piston 12.4 is less than the height of the sample, which is convenient for placing the sample. After the sample is placed, the servo 12.1 drives the driving arm 12.8 to swing, and the notch 12.81 toggles the sliding pin 12.7, so that the sleeve 12.2 moves upward along the fixed piston 12.4 to the highest position. The initial state of the sleeve 12.2 is in the lowest position, such as Figure 6 The outer wall of the sleeve 12.2 is integrally formed with a circumferentially movable snap ring 12.22 connected to the bottom surface of the test platform 13, which plays a further limiting role when the sleeve 12.2 moves upward.

[0062] The inner wall of the sleeve 12.2 is provided with a groove 12.21 along the circumference, and a sealing rubber tube 12.3 is embedded in the groove 12.21. The sealing rubber tube 12.3 includes an annular cavity 12.31 and three sealing rubber rings 12.32 integrally formed with the inner side of the annular cavity 12.31. The sealing rubber rings 12.32 are connected to the air chamber of the annular cavity 12.31. The outer walls of the annular cavity 12.31 on both sides of the sealing rubber rings 12.32 are clamped. There is an elastic retaining ring 12.33, which limits the annular cavity 12.31; the other end of the air supply pipe 3 is sealed and passes through the side wall of the sleeve 12.2 and is connected to the air chamber of the annular cavity 12.31; before the sleeve 12.2 moves upward from the low position, the air supply system is controlled to inhale air from the air supply pipe 3 to retract the sealing rubber tube 12.3 to prevent the sleeve 12.2 from touching and rubbing the sample during the upward movement; when the sleeve 12.2 moves upward to the highest position, as shown in FIG. Figure 7 As shown, the sealing rubber tube 12.3 corresponds to the position of the sample. The air supply system is controlled to supply air to the air supply pipeline 3 to expand the sealing rubber tube 12.3, ensuring that the sealing rubber ring 12.32 fits the side wall of the sample. The sealing rubber rings 12.32 at both ends correspond to the upper and lower ends of the sealed sample.

[0063] like Figure 8As shown in the figure, a horizontally arranged test platform 13 is fixedly connected above the support platform 16. Through holes 13.1 corresponding to each sample body 12 are provided on the test platform 13, and the sleeve 12.2 of the sample body 12 movably passes through the corresponding through holes 13.1; a support 14 is connected to the test platform 13, and a pressing mechanism 15 is correspondingly connected to the support 14 directly above each sample body 12. The pressing mechanism 15 includes a top rod 15.1 and a sleeve 15.2 coaxially and slidably sleeved on the top rod 15.1. The top end of the sleeve 15.2 is fixedly connected to the support 14. The sleeve 15.2 is coaxial with the corresponding fixed sleeve 12.2. A spring 15.3 abutting against the top end of the top rod 15.1 is arranged inside the sleeve 15.2. A limiting edge is integrally formed along the circumferential direction on the inner wall of the bottom end of the sleeve 15.2, and a convex edge clamped on the limiting edge of the corresponding sleeve 15.2 is integrally formed along the circumferential direction on the outer wall of the top end of the top rod 15.1, which plays a limiting role to prevent the top rod 15.1 from disengaging from the sleeve 15.2. The setting of the limiting edge and the convex edge is a conventional technology in the art, and the specific structure is not separately shown in the drawings; the top rods 15.1 of the respective pressing mechanisms 15 are connected through a connecting frame 15.4; before placing the sample, the top rod 15.1 is lifted, and the spring 15.3 is compressed under force. After placing the sample, the top rod 15.1 is released, so that the bottom end of the top rod 15.1 contacts the center of the sample, and under the action of the spring 15.3, it is ensured that the bottom end of the sample is closely attached to the fixed piston 12.4.

[0064] Example 2: The method for detecting the air permeability of an anode carbon block includes the following steps:

[0065] Sampling, using a hollow drill to take a cylindrical sample from the anode carbon block. The diameter of the sample is 50 mm and the length is 75 mm;

[0066] Pre-treatment of the sample includes the following steps: Step 1. Sample preparation: Cut off the ends to take a 20-mm-long sample and blow off the attachments on it; Step 2. Drying: Dry at a temperature of 110°C ± 5°C for 12 hours; Step 3. Measuring the height of the sample: Use a caliper to measure the height of the cylindrical sample every 90° along the circumference, with a deviation not exceeding 0.02 mm, and calculate the average value hs of the height measurement; Step 4. Measuring the diameter of the sample: Use a caliper to measure two groups of diameter data, with an interval of 90° between the two groups. The deviation of each group does not exceed 0.02 mm. The diameter data of each group is measured four times, once at each of the upper and lower ends of the sample and twice at the midpoint of the axis, calculate the average value ds of the two groups of diameter measurements, and then calculate the cross-sectional area A of the sample;

[0067] It further includes the following steps:

[0068] (1) Lift each top rod through the connecting frame, and place a standard sample and each sample to be tested on the fixed piston along the inner wall of the sleeve of the corresponding sample body;

[0069] (2) The air pump is started to suck air from the air supply pipeline, causing the sealed rubber pipe fitting to retract;

[0070] (3) The steering gear is started. Under the cooperation of the notch and the sliding pin, the sleeve is driven by the driving arm to move upward to the highest position;

[0071] (4) The connecting frame is loosened, so that the bottom end of the ejector rod contacts the center of the sample. Under the action of the spring, the bottom end of the sample is closely attached to the fixed piston;

[0072] (5) The electromagnetic directional valve is switched to the right working position. The air pump sucks air from the atmosphere and sends it into the sealed rubber pipe fitting through the air supply pipeline. The sealing rubber ring expands to seal the side wall of the sample;

[0073] (6) The electromagnetic main valve and one electromagnetic on-off valve corresponding to the standard sample are opened. The vacuum pump is used to evacuate. When the liquid level in the U-shaped tube manometer reaches the position of sensor three, the electromagnetic main valve is closed. The air flow through the sample reduces the vacuum degree. When the liquid level in the U-shaped tube manometer reaches sensor two, record the time at this moment. When the liquid level reaches sensor one, record the time at this moment again, and then calculate the time difference tc between the two times;

[0074] (7) When the liquid level in the U-shaped tube manometer in step (6) returns to the equilibrium marking line position, close the corresponding electromagnetic on-off valve to complete the detection of the standard sample;

[0075] (8) Repeat steps (6) and (7) to detect the time differences ts of other samples in turn;

[0076] (9) After all samples are detected, turn off the vacuum pump and the electromagnetic on-off valve; switch the electromagnetic directional valve to the left working position. The air pump sucks air from the air supply pipeline, causing the sealed rubber pipe fitting to retract, and then turn off the air pump; lift each ejector rod upward. The steering gear controls the sleeve to move downward to the low position, so that the upper parts of the samples are exposed, facilitating their removal. Replace the next batch of samples to be tested, and then repeat the above steps (1) to (8) for detection;

[0077] (10) Using the known air permeability Dc of the standard sample and the detected time difference tc, calculate the correction factor fc by formula (1):

[0078]

[0079] In the formula, fc - correction factor, unit is cubic meters per second;

[0080] tc - time difference, unit is second;

[0081] Dc - air permeability of the standard sample, unit is 10 -9 square meters;

[0082] 1963 — The cross-sectional area of the sample corresponding to a test sample diameter of 50 mm, in square millimeters;

[0083] 20 — The height of the test sample, in millimeters.

[0084] (11) Calculate the air permeability Ds of the test sample according to formula (2):

[0085]

[0086] Where Ds is the air permeability of the test sample, in 10 -9 square meters;

[0087] ts is the time difference, in seconds;

[0088] hs is the average height of the sample, in millimeters;

[0089] A is the cross-sectional area of the sample, in square millimeters.

[0090] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. An air permeability detection device for anodes, characterized in that It includes a vacuum system, a gas supply system, and more than one set of sample measurement bodies; The sample measurement body includes a steering gear, a sleeve, a sealed rubber pipe fitting, and a fixed piston connected to a support platform. A blind hole is coaxially opened at the top end of the fixed piston. A vacuum channel is provided inside the fixed piston. The top end of the vacuum channel communicates with the blind hole, and the bottom end of the vacuum channel communicates with the vacuum system. A U-shaped tube manometer is connected to the vacuum system; The sleeve is slidably sleeved on the fixed piston, and a sliding pin is fixed on the outer wall of the sleeve; the steering gear is fixed on the support platform, the output shaft of the steering gear is connected with a driving arm, and a notch sleeved on the sliding pin is opened on the driving arm; A groove is circumferentially opened on the inner wall of the sleeve, and the sealed rubber pipe fitting is embedded and installed in the groove. The air chamber of the sealed rubber pipe fitting communicates with the gas supply system.

2. The air permeability detection device for an anode carbon block according to claim 1, characterized in that, A porous filter paper is laid at the bottom of the blind hole, and a sponge rubber is plugged at the channel opening of the vacuum channel in the blind hole.

3. The air permeability detection device for an anode carbon block according to claim 1, wherein The sealed rubber pipe fitting includes an annular cavity and more than one sealing rubber ring integrally formed with the inner side of the annular cavity. The sealing rubber ring communicates with the air chamber of the annular cavity.

4. The air permeability detection device for an anode carbon block according to claim 3, wherein, Elastic retaining rings are clamped on the outer walls of the annular cavity on both sides of the sealing rubber ring.

5. The air permeability detection device for an anode carbon block according to claim 1, characterized in that, A horizontally arranged test platform is fixedly connected above the support platform. Through holes corresponding to each sample measurement body are opened on the test platform, and the sleeve of the sample measurement body movably passes through the corresponding through holes.

6. The air permeability detection device for an anode carbon block according to claim 5, characterized in that, A bracket is connected to the test platform, and a pressing mechanism is correspondingly connected to the bracket directly above each sample measurement body; the pressing mechanism includes a top rod and a sleeve coaxially slidably sleeved on the top rod. The top end of the sleeve is fixedly connected to the bracket. The sleeve is coaxial with the corresponding fixed sleeve, and a spring abutted against the top end of the top rod is arranged inside the sleeve.

7. An air permeability detection device for anodes as claimed in claim 1, wherein, The gas supply system includes an air pump, an electromagnetic reversing valve, and a gas supply pipeline. One end of the gas supply pipeline is hermetically passed through the side wall of the sleeve and communicates with the air chamber of the annular cavity. The other end of the gas supply pipeline is connected to one interface of the electromagnetic reversing valve. The air inlet and outlet of the air pump are correspondingly connected to two interfaces on the electromagnetic reversing valve.

8. The air permeability detection device for an anode carbon block according to claim 1, characterized in that, The vacuum system includes a vacuum pump, a vacuum tank, vacuum branch pipes, and a vacuum main pipe. One vacuum branch pipe is connected to the bottom end of the vacuum channel of each fixed piston. Each vacuum branch pipe is connected to one end of the vacuum main pipe. The other end of the vacuum main pipe is connected to one end of the U-shaped tube manometer. The vacuum main pipe is connected to the inlet of the vacuum tank through a bypass pipeline. The outlet of the vacuum tank is connected to the vacuum pump; an electromagnetic on-off valve is installed on the vacuum branch pipe, and an electromagnetic main valve is installed on the bypass pipeline.

9. A detection method using the anode carbon block air permeability detection device according to any one of claims 1 to 8, which includes sampling and sample pretreatment, and is characterized in that, It further includes the following steps: (1) Lift each top rod through a connecting frame, and place a standard sample and each sample to be measured along the inner wall of the sleeve of the corresponding sample measurement body on the fixed piston; (2) Start the air pump, inhale air from the gas supply pipeline, and retract the sealed rubber pipe fitting; (3) Start the steering gear, and drive the sleeve to move upward to a high position by the driving arm under the cooperation of the notch and the sliding pin; (4) Loosen the connecting frame so that the bottom end of the ejector rod contacts the center of the sample. Under the action of the spring, the bottom end of the sample fits tightly against the fixed piston. (5) Switch the electromagnetic directional control valve to the right working position. The air pump sucks air from the atmosphere and sends it into the sealed rubber pipe fitting through the air supply pipeline. The sealing rubber ring expands to seal the side wall of the sample. (6) Turn on the main electromagnetic valve and one electromagnetic on-off valve corresponding to the standard sample, and evacuate the air with a vacuum pump. When the liquid level in the U-tube manometer reaches the position of Sensor 3, turn off the main electromagnetic valve. The air flow through the sample reduces the vacuum degree. When the liquid level in the U-tube manometer reaches Sensor 2, record the time at this moment. When the liquid level reaches Sensor 1, record the time again. Then calculate the time difference t between the two times. c ; (7) When the liquid level in the U-tube manometer returns to the equilibrium marking line position in step (6), close the corresponding electromagnetic on-off valve to complete the detection of the standard sample. (8) Repeat steps (6) and (7) to sequentially detect the time difference ts of other samples. (9) After all samples are detected, turn off the vacuum pump and the electromagnetic on-off valve; switch the electromagnetic directional control valve to the left working position. The air pump sucks air from the air supply pipeline to retract the sealed rubber pipe fitting, and then turn off the air pump; lift each ejector rod upward, and the servo motor controls the sleeve to move downward to the low position to expose the upper part of each sample, facilitating the removal of the samples and replacing them with the next batch of samples to be tested, and then repeat the above steps (1) to (8) for detection. (10) Using the known air permeability D of the standard sample c and the detected time difference t c , calculate the correction factor f according to formula (1) c : where f c — correction factor, unit: cubic meter per second; t c — Time difference, in seconds; D c — Air permeability of the standard sample, in units of 10 -9 square meters; 1963—The cross-sectional area of the sample corresponding to a test sample diameter of 50 mm, in square millimeters. 20—The height of the test sample, in millimeters. (11) Calculate the air permeability D of the test sample according to formula (II). s : where D s — air permeability of the test sample, unit: 10 -9 square meters t s — Time difference, in seconds; h s — The average height of the sample, in millimeters; A—The cross-sectional area of the sample, in square millimeters.

10. A method for detecting the air permeability of an anode carbon block according to claim 9, characterized in that, During sampling, a cylindrical sample is taken from a predetermined position on the anode carbon block using a hollow drill. The diameter of the sample is 50 mm and the length is 75 mm. The sample pretreatment includes the following steps: Step 1. Sample preparation: Cut off the ends to obtain a sample with a length of 20 mm and blow off the attachments on it. Step 2. Drying: Dry at a temperature of 110°C ± 5°C for 12 hours. Step 3. Measure the height of the sample: Use a caliper to measure the height of the cylindrical sample every 90° along the circumference, with a deviation not exceeding 0.02 mm, and calculate the average value h of the height measurement s ; Step 4. Measure the diameter of the sample: Use a caliper to measure two sets of diameter data, with an interval of 90° between the two sets. The deviation of each set does not exceed 0.02 mm. The diameter data is measured four times for each set, once at each of the upper and lower ends of the sample and twice at the midpoint of the axis. Calculate the average value d of the two sets of diameter measurements. s , and then calculate the cross-sectional area A of the sample.

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