Machine-made sand quality on-line detection equipment and detection method thereof

Abstract

The invention discloses machine-made sand quality on-line detection equipment and a detection method thereof, and relates to the technical field of machine-made sand quality detection.The machine-made sand quality on-line detection equipment comprises a sample feeding barrel, a solution volume measurer is communicated with the sample feeding barrel, and a sand sample circulating barrel is communicated with a discharging opening of the sample feeding barrel; the filtering mechanism is arranged in the sand sample circulating cylinder and divides the sand sample circulating cylinder into an upper cavity and a lower cavity; the water content can be calculated through the machine-made sand quality online detection equipment in combination with a specific gravity method, and the drying step is omitted. Through classification and partition detection of the stone powder and the stone-powder-removed sand sample, the content of the stone powder is measured by adopting a nephelometry, so that redundant calculation of an image method on extremely fine particles can be reduced, the testing precision of the content of the stone powder is improved, the particle number of sand per unit mass and the turbidity of testing liquid are reduced, and by adopting circular flowing and recognition of the stone-powder-removed sand sample, the detection accuracy of the stone powder content is improved. The reliability and repeatability of sand sample particle detection by an image method are improved, and the measurement precision of the fineness modulus of the sand sample is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of the quality detection of manufactured sand, in particular to an on-line detection device for the quality of manufactured sand and a detection method thereof. Background Art

[0002] As a commonly used material in modern construction projects, the quality detection of manufactured sand is crucial for ensuring the safety and durability of construction projects. However, there are some drawbacks in the existing manufactured sand quality detection technologies:

[0003] 1. Moisture content detection: Traditional moisture content detection methods (such as the drying method) are time-consuming and not suitable for on-line real-time detection. Moreover, the sampling may be inaccurate, resulting in low repeatability and large errors in the detection results. Although some sensors can provide on-line detection, their accuracy is limited. Especially when the moisture content is less than 2%, the detection accuracy will be significantly reduced. In addition, there are various forms of water in manufactured sand, and these sensors generally can only detect a single form of water, which limits the comprehensiveness and scope of application of the detection.

[0004] 2. Stone powder content detection: The stone powder content and particle gradation in manufactured sand have a significant impact on the performance of concrete. However, the existing detection methods are difficult to detect and determine the stone powder content and particle gradation of sand samples in real time. Generally, a series of steps such as drying, grading and screening, weighing and calculation are required to obtain the stone powder content and the fineness modulus parameter of the sand. Moreover, during the test process, the detection results may be inaccurate due to human errors or differences in operation proficiency.

[0005] In view of this, how to provide a manufactured sand quality detection device that can partially or completely solve the above technical problems is an urgent need for those skilled in the art. Summary of the Invention

[0006] The purpose of the present invention is to provide an on-line detection device for the quality of manufactured sand and a detection method thereof to solve the problems existing in the prior art.

[0007] To achieve the above purpose, the present invention provides the following solution: The present invention provides an on-line detection device for the quality of manufactured sand, including:

[0008] A sample feeding cylinder, which has a feeding port for placing wet sand into the sample feeding cylinder and mixing it with the water in the sample feeding cylinder;

[0009] A solution volume measuring device, which is communicated with the sample feeding cylinder for detecting the change amount of the solution volume in the sample feeding cylinder.

[0010] Further, it further includes:

[0011] A sand sample circulating cylinder, which is communicated with the discharge port of the sample feeding cylinder, and a first valve is arranged at the communication part;

[0012] A filtering mechanism, which is arranged in the sand sample circulation cylinder and divides the sand sample circulation cylinder into an upper cavity and a lower cavity. The filtering mechanism can filter the stone powder into the lower cavity;

[0013] A first stirrer, which is arranged in the lower cavity;

[0014] An SS concentration measuring device, which is arranged in the lower cavity and is used to measure the SS concentration in the lower cavity.

[0015] Furthermore, the filtering mechanism is an upper sieve mesh and a lower sieve mesh that are rotatably arranged in the sand sample circulation cylinder. The upper sieve mesh and / or the lower sieve mesh can rotate between a first position and a second position. When the upper sieve mesh and / or the lower sieve mesh are in the first position, the mesh holes of the upper sieve mesh correspond to the mesh holes of the lower sieve mesh; when the upper sieve mesh and / or the lower sieve mesh are in the second position, the mesh holes of the upper sieve mesh are misaligned with the mesh holes of the lower sieve mesh.

[0016] Furthermore, it also includes an inclined vibrating base. The inside of the inclined vibrating base has a vibrator, and its upper surface slopes downward. The lower surface of the sand sample circulation cylinder is fixedly arranged on the upper surface of the inclined vibrating base.

[0017] Furthermore, it also includes:

[0018] A second stirrer, which is arranged in the upper cavity;

[0019] A first sand sample circulation pipeline, one end of which is communicated with the upper cavity, and a second valve is arranged at the communication part;

[0020] An image acquisition and analysis mechanism, whose water inlet end is communicated with the other end of the first sand sample circulation pipeline and is used to acquire sand sample images;

[0021] A second sand sample circulation pipeline, one end of which is communicated with the upper cavity, and the other end is communicated with the water outlet end of the image acquisition and analysis mechanism.

[0022] Furthermore, the image acquisition and analysis mechanism includes:

[0023] A transparent chamber, and the water inlet end and the water outlet end are respectively arranged at the upper and lower ends of the transparent chamber;

[0024] A CCD image acquisition and analysis device, whose acquisition end corresponds to the transparent chamber;

[0025] A light source, and the CCD image acquisition and analysis device and the light source are respectively located on the front and back sides of the transparent chamber.

[0026] Furthermore, a drainage pipeline is communicated with the second sand sample circulation pipeline, a drainage valve is arranged on the drainage pipeline, and a circulation pump is arranged on the first sand sample circulation pipeline and / or the second sand sample circulation pipeline.

[0027] Further, the upper sieve is rotatably arranged on the inner side wall of the sand sample circulation cylinder through a rotary power-off spring resetter. When the rotary power-off spring resetter is powered on, the upper sieve is in the first position, and when the rotary power-off spring resetter is powered off, the upper sieve is in the second position.

[0028] The present invention also provides an on-line detection method for the quality of manufactured sand, which applies an on-line detection device for the quality of manufactured sand and includes the following steps:

[0029] S1: Cleaning: Open the first valve, the second valve and the drain valve, and inject clear water from the feed port of the sample feed cylinder to clean the equipment;

[0030] S2: Close the first valve, the second valve and the drain valve, and take a wet sand sample. The mass of the wet sand is m;

[0031] S3: Fill water in the sample feed cylinder, and record the liquid volume V0 in the feed cylinder through the solution volume measuring device; Add the wet sand into the sample feed cylinder from the feed port, and record the liquid volume V1 in the feed cylinder;

[0032] Calculate the moisture content θ by the specific gravity method:

[0033] m = V s ρ s + V w ρ w

[0034] ΔV = V s + V w

[0035] ΔV = V1 - V0

[0036] m = V w ρ w +(ΔV - V w )ρ s = ΔVρ s + V w (ρ w - ρ s )

[0037]

[0038] Where: m: mass of wet sand, g; V s : volume of sand in wet sand, cm 3 ; V w : volume of water in wet sand, cm 3 ; ρ s : saturated surface dry density of sand, g / cm 3 ; ρ w : density of water, g / cm3 ; V0: The volume of the liquid added into the wet sand feeding cylinder, cm 3 ; V1: The volume of the liquid in the feeding cylinder after adding wet sand, cm 3 ; m s : The mass of sand in the sampled wet sand, g; θ: The moisture content of the wet sand, %.

[0039] S4: Wet sand and water are mixed in the sample feeding cylinder to form a sand sample. Open the first valve and discharge the sand sample into the upper chamber; the upper sieve and / or the lower sieve rotate to the first position so that the meshes of the upper sieve and the lower sieve correspond. Start the vibrator in the inclined vibration base to separate the stone powder and sand in the sand sample. The stone powder passes through the meshes of the upper sieve and the lower sieve and enters the lower chamber, and the sand is retained in the upper chamber. The upper sieve and / or the lower sieve rotate to the second position;

[0040] S5: Turn on the first stirrer, measure the SS concentration in the lower chamber using the SS concentration measuring device, and calculate the stone powder content w p :

[0041] m p =(0.9734SS 2 +139.16SS + 24.044)V

[0042]

[0043] Where: SS: The turbidity value of the lower chamber, mg / l; V: The volume of the lower chamber, l; m p : The mass of stone powder, g; w p : The stone powder content, %.

[0044] S6: After the stone powder and sand are separated, the sand sample becomes a sand sample without stone powder. Turn on the second stirrer, the second valve and the circulation pump, and the sand sample without stone powder circulates in the first sand sample circulation pipeline, the transparent chamber, the second sand sample circulation pipeline and the upper chamber;

[0045] S7: Turn on the light source and the CCD image acquisition and analysis device, obtain the image information of the sand sample without stone powder in the transparent chamber, obtain the quantity and volume of the sand in the particle size range of D1 - D5 according to the image information of the sand sample without stone powder, and record the frequencies (%) ν1 - ν5 in the particle size range of D1 - D5; The particle size ranges (mm) of D1 - D5 are respectively: D1: 4.75 - 2.36; D2: 2.36 - 1.18; D3: 1.18 - 0.6; D4: 0.6 - 0.3; D5: 0.3 - 0.15;

[0046] Calculate the fineness modulus M x :

[0047]

[0048] wherein, f1 = ν1(1 - w p );f2 = ν2(1 - w p );f3 = ν3(1 - w p );f4 = ν4(1 - w p );f5 = ν5(1 - w p );f6 = w p 。

[0049] The present invention discloses the following technical effects:

[0050] 1. By combining the on-line detection equipment for the quality of manufactured sand with the specific gravity method, the moisture content can be calculated, and the drying step is omitted compared with the traditional technology.

[0051] 2. The stone powder less than 0.15 mm is separated from the sand of 0.15 - 4.75 mm through the filtering mechanism, and the turbidity method and the image method are respectively used to measure the stone powder content and the fineness modulus of the sand sample after removing the stone powder. Measuring the stone powder content by the turbidity method can reduce the redundant calculation of the image method for extremely fine particles. Compared with the image method, the test accuracy of the stone powder content is greatly improved; for the sand sample after removing the stone powder, since the stone powder is removed, the number of particles per unit mass of the sand and the turbidity of the test liquid are greatly reduced. Therefore, the quality of the recycled sand sample after removing the stone powder can be improved, and further the reliability and repeatability of the image method can be enhanced, and the measurement accuracy of the fineness modulus can be improved.

[0052] 3. The present invention can greatly improve the detection efficiency, can complete a detection within 5 - 10 minutes (the traditional equipment requires at least 30 minutes), and greatly simplifies the operation process, reduces the detection difficulty. The whole operation is automatically completed by the machine. The prepared detection standard samples have good consistency, ensuring the accuracy of the detection results. More importantly, it can be used for on-line detection at any position of the manufactured sand production line, and the detection application occasions are not limited by processes and positions; the on-line moisture detection equipment for manufactured sand provided by the present invention has a compact structure, occupies a small space, and is convenient for installation, use and maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to these drawings.

[0054] Figure 1 is a schematic structural diagram of the present invention;

[0055] Figure 2 is a schematic diagram when the upper sieve is in the first position;

[0056] Figure 3 Schematic diagram when the upper sieve rotates to the second position;

[0057] Figure 4 Fitting curve of SS concentration and stone powder mass;

[0058] Wherein, 1. Sample feed cylinder; 2. Solution volume measuring device; 3. Sand sample circulation cylinder; 301. Upper cavity; 302. Lower cavity; 4. First valve; 5. First stirrer; 6. SS concentration measuring device; 7. Upper sieve; 8. Inclined vibration base; 9. Second stirrer; 10. First sand sample circulation pipeline; 11. Second sand sample circulation pipeline; 12. Transparent chamber; 13. CCD image acquisition and analysis device; 14. Light source; 15. Drainage pipeline; 16. Drainage valve; 17. Drainage pipe; 18. Second valve. Specific embodiments

[0059] 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. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0060] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0061] Embodiment 1

[0062] As Figure 1 shown, the embodiment of the present invention provides an on-line detection device for the quality of manufactured sand, including: a sample feed cylinder 1, which has a feed port for placing wet sand into the sample feed cylinder 1 and mixing it with the water in the sample feed cylinder 1; a solution volume measuring device 2, which is connected to the sample feed cylinder 1 and is used to detect the change in the solution volume in the sample feed cylinder 1, and the solution volume measuring device 2 adopts a U-shaped tube type.

[0063] In this embodiment, it further includes: a sand sample circulation cylinder 3, which is connected to the discharge port of the sample feed cylinder 1, and a first valve 4 is provided at the connection; a filtering mechanism, which is arranged in the sand sample circulation cylinder 3 and divides the sand sample circulation cylinder 3 into an upper cavity 301 and a lower cavity 302, and the filtering mechanism can filter the stone powder into the lower cavity 302; a first stirrer 5, which is arranged in the lower cavity 302; an SS concentration measuring device 6, which is arranged in the lower cavity 302 and is used to measure the SS concentration in the lower cavity 302; a drainage pipe 17, which is arranged at the bottom of the lower cavity 302 and is used to discharge the liquid in the lower cavity 302, and a drainage valve is provided on the drainage pipe 17.

[0064] The filtering mechanism includes an upper sieve 7 and a lower sieve. The upper sieve 7 is rotatably arranged between a first position and a second position on the inner sidewall of the sand sample circulating cylinder 3 through a rotary power-off spring reset device. When the rotary power-off spring reset device is powered on, the upper sieve 7 is in the first position; when the rotary power-off spring reset device is powered off, the upper sieve 7 is in the second position. The lower sieve is located below the upper sieve 7 and is fixedly arranged on the inner sidewall of the sand sample circulating cylinder 3. When the upper sieve 7 is in the first position, the mesh of the upper sieve 7 corresponds to the mesh of the lower sieve; when the upper sieve 7 is in the second position, the mesh of the upper sieve 7 is misaligned with the mesh of the lower sieve, and the rotation angle between the first position and the second position is 12°.

[0065] In this embodiment, it further includes an inclined vibration base 8. The inclined vibration base 8 has a vibrator inside, and its upper surface is inclined downward. The lower surface of the sand sample circulating cylinder 3 is fixedly arranged on the upper surface of the inclined vibration base 8. The purpose of setting it to be inclined is to facilitate the circulating flow of sand grains and avoid the slowdown of water flow movement in the corner part or the accumulation of some fine sand at the bottom due to self-weight sedimentation during circulation.

[0066] In this embodiment, it further includes: a second stirrer 9, arranged in the upper cavity 301; a first sand sample circulation pipeline 10, one end of which is communicated with the upper cavity 301, and a second valve 18 is arranged at the communication position; an image acquisition and analysis mechanism, the water inlet end of which is communicated with the other end of the first sand sample circulation pipeline 10 for acquiring sand sample images; a second sand sample circulation pipeline 11, one end of which is communicated with the upper cavity 301 and the other end is communicated with the water outlet end of the image acquisition and analysis mechanism.

[0067] In this embodiment, the image acquisition and analysis mechanism includes: a transparent chamber 12, the water inlet end and the water outlet end are respectively arranged at the upper and lower ends of the transparent chamber 12; a CCD image acquisition and analysis device 13, the acquisition end of which corresponds to the transparent chamber 12; a light source 14, and the CCD image acquisition and analysis device 13 and the light source 14 are respectively located on the front and back sides of the transparent chamber 12.

[0068] In this embodiment, a drainage pipeline 15 is communicated with the second sand sample circulation pipeline 11, a drainage valve 16 is arranged on the drainage pipeline 15, and a circulation pump is arranged on the first sand sample circulation pipeline 10 and / or the second sand sample circulation pipeline 11.

[0069] The present invention also provides an on-line detection method for the quality of manufactured sand, which is applied to the on-line detection equipment for the quality of manufactured sand and includes the following steps:

[0070] S1: Cleaning: Open the first valve 4, the second valve 18 and the drainage valve 16, and inject clean water from the feed port of the sample feed cylinder 1 to clean the equipment;

[0071] S2: After the cleaning is completed, close the first valve 4, the second valve 18, and the drain valve 16. Open the liquid discharge valve to empty all the remaining liquid in the sand sample circulation cylinder 3, and then close the liquid discharge valve; take wet sand samples from the belt conveyor, and the mass of the wet sand is m.

[0072] S3: Fill the sample feeding cylinder 1 with water. The amount of water filled should ensure that it does not overflow after adding the wet sand. Record the liquid volume V0 in the feeding cylinder through the solution volume measurer 2; add the wet sand into the sample feeding cylinder 1 from the feeding port, and record the liquid volume V1 in the feeding cylinder.

[0073] Calculate the moisture content θ by the specific gravity method:

[0074] m = V s ρ s + V w ρ w

[0075] ΔV = V s + V w

[0076] ΔV = V1 - V0

[0077] m = V w ρ w +(ΔV - V w )ρ s = ΔVρ s + V w (ρ w - ρ s )

[0078]

[0079] Where: m: mass of wet sand, g; V s : volume of sand in wet sand, cm 3 ; V w : volume of water in wet sand, cm 3 ; ρ s : saturated surface dry density of sand, g / cm 3 ; ρ w : density of water, g / cm 3 ; V0: liquid volume in the feeding cylinder before adding wet sand, cm 3 ; V1: liquid volume in the feeding cylinder after adding wet sand, cm 3 ; m s : mass of sand in the sampled wet sand, g; θ: moisture content of wet sand, %.

[0080] S4: Wet sand and water are mixed in the sample feeding cylinder 1 to form a sand sample. Open the first valve 4 to discharge the sand sample into the upper chamber. Under normal conditions, the upper sieve 7 is in the second position. Rotate the upper sieve 7 by 12° to the first position so that the mesh openings of the upper sieve 7 and the lower sieve correspond. Start the vibrator in the inclined vibration base 8 and vibrate for 30 s to separate the stone powder and sand in the sand sample. The stone powder passes through the mesh openings of the upper sieve 7 and the lower sieve and enters the lower chamber, while the sand is retained in the upper chamber. Then rotate the upper sieve 7 back to the second position;

[0081] S5: Turn on the first stirrer 5. The first stirrer 5 is a low-speed stirrer with a rotation speed of 100 - 120 revolutions per minute. Use the SS concentration measuring device 6 (the SS concentration measuring device 6 is a device used to measure the concentration of suspended solids (SS) in water) to measure the SS concentration in the lower chamber and calculate the stone powder content w p :

[0082] m p =(0.9734SS 2 +139.16SS + 24.044)V

[0083]

[0084] where: SS: turbidity value in the lower chamber, mg / l; V: volume of the lower chamber, l; m p : mass of stone powder, g; w p : stone powder content, %.

[0085] S6: After the stone powder and sand are separated, the sand sample becomes a sand sample without stone powder. Turn on the second stirrer 9, the second valve 18 and the circulation pump. The second stirrer 9 is a high-speed stirrer. The sand sample without stone powder circulates in the first sand sample circulation pipeline 10, the transparent chamber 12, the second sand sample circulation pipeline 11 and the upper chamber;

[0086] S7: After the sand sample without stone powder reaches a stable flow state, turn on the light source 14 and the CCD image acquisition and analysis device 13 to obtain the image information of the sand sample without stone powder in the transparent chamber 12. According to the image information of the sand sample without stone powder, obtain the quantity and volume of the sand in the particle size range of D1 - D5, and record the frequency (%) ν1 - ν5 in the particle size range of D1 - D5; The particle size ranges (mm) of D1 - D5 are respectively: D1: 4.75 - 2.36; D2: 2.36 - 1.18; D3: 1.18 - 0.6; D4: 0.6 - 0.3; D5: 0.3 - 0.15;

[0087] Calculate the fineness modulus M x :

[0088]

[0089] Among them, f1 = ν1(1 - w p ); f2 = ν2(1 - w p ); f3 = ν3(1 - w p ); f4 = ν4(1 - w p ); f5 = ν5(1 - w p ); f6 = w p .

[0090] In the above steps, steps S1 - S3 are for measuring the moisture content of wet sand by the specific gravity method; S4 - S5 are for measuring the stone powder content by the turbidity method, and S6 - S7 are for measuring the fineness modulus by the image method.

[0091] S8: Repeat step S1 to clean the equipment again.

[0092] Example 2

[0093] The difference between this example and Example 1 is that the stone powder mass is further measured.

[0094] The specific method is as follows:

[0095] Weigh 0, 0.1, 0.2, 0.5, 1, 2, 5, 10, 15, 20, 50 g of stone powder and place them into the water in the lower chamber respectively. Use the method disclosed in step S5 of Example 1 to measure the SS concentration in the lower chamber three times. The three SS concentrations are SS1, SS2, and SS3 respectively. Take the average value of the three SS concentrations as the SS value corresponding to this weight of stone powder. The specific parameters are as follows in the table:

[0096] Quality of stone powder SS1 SS2 SS3 SS Variance g / l mg / l mg / l mg / l mg / l mg / l 0 6.8 6.8 6.8 6.80 0.00 0.1 25.4 24.9 24.5 24.93 0.20 0.5 89.5 91.5 90.7 90.57 1.01 1 171.6 173.6 173.3 172.83 1.16 2 350.6 348.5 345.9 348.33 5.54 5 745.1 745.1 744.9 745.00 0.01 10 1490 1530 1534 1518.00 592.00 15 2323 2296 2292 2305.25 199.58 20 3192 3231 3201 3208.00 417.00 50 9410 9390 9447 9415.67 836.33

[0097] Perform polynomial fitting on the SS concentration and the stone powder mass to obtain the fitting curve as Figure 4 shown.

[0098] Compare the SS concentration measured in step S5 of Example 1 with the fitting curve to obtain the mass of the stone powder that has sunk into the lower chamber.

[0099] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention, 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. Therefore, it should not be construed as a limitation to the present invention.

[0100] The embodiments described above are only descriptions of the preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. An on-line detection device for the quality of manufactured sand, characterized in that, Comprising: A sample feed cylinder (1) having a feed port for placing wet sand into the sample feed cylinder (1) and mixing it with water inside the sample feed cylinder (1); A solution volume measuring device (2) communicating with the sample feed cylinder (1) for detecting the change in the volume of the solution inside the sample feed cylinder (1).

2. The on-line detection device for the quality of manufactured sand according to claim 1, characterized in that Further comprising: A sand sample circulation cylinder (3) communicating with the discharge port of the sample feed cylinder (1), and a first valve (4) is provided at the connection; A filtering mechanism, which is arranged inside the sand sample circulation cylinder (3) and divides the sand sample circulation cylinder (3) into an upper cavity (301) and a lower cavity (302), and the filtering mechanism can filter stone powder into the lower cavity (302); A first stirrer (5) arranged in the lower cavity (302); An SS concentration measuring device (6) arranged in the lower cavity (302) for measuring the SS concentration in the lower cavity (302).

3. An on-line detection device for the quality of manufactured sand according to claim 2, characterized in that, The filtering mechanism is an upper sieve mesh (7) and a lower sieve mesh rotatably arranged inside the sand sample circulation cylinder (3), and the upper sieve mesh (7) and / or the lower sieve mesh can rotate between a first position and a second position. When the upper sieve mesh (7) and / or the lower sieve mesh is in the first position, the mesh openings of the upper sieve mesh (7) correspond to the mesh openings of the lower sieve mesh; when the upper sieve mesh (7) and / or the lower sieve mesh is in the second position, the mesh openings of the upper sieve mesh (7) are offset from the mesh openings of the lower sieve mesh.

4. An on-line detection device for the quality of manufactured sand according to claim 3, characterized in that, Further comprising an inclined vibrating base (8) having a vibrator inside, and its upper surface slopes downward, and the lower surface of the sand sample circulation cylinder (3) is fixedly arranged on the upper surface of the inclined vibrating base (8).

5. An on-line detection device for the quality of manufactured sand according to claim 4, characterized in that, Further comprising: A second stirrer (9) arranged in the upper cavity (301); A first sand sample circulation pipe (10) having one end communicating with the upper cavity (301), and a second valve (18) is provided at the connection; An image acquisition and analysis mechanism, whose water inlet end communicates with the other end of the first sand sample circulation pipe (10) for acquiring sand sample images; A second sand sample circulation pipe (11) having one end communicating with the upper cavity (301) and the other end communicating with the water outlet end of the image acquisition and analysis mechanism.

6. The on-line detection device for the quality of manufactured sand according to claim 5, characterized in that The image acquisition and analysis mechanism comprises: A transparent chamber (12) with a water inlet end and a water outlet end respectively arranged at the upper and lower ends of the transparent chamber (12); A CCD image acquisition and analysis device (13) whose acquisition end corresponds to the transparent chamber (12); A light source (14), and the CCD image acquisition and analysis device (13) and the light source (14) are respectively located on the front and back sides of the transparent chamber (12).

7. An on-line detection device for the quality of manufactured sand according to claim 6, characterized in that, A drainage pipe (15) is connected to the second sand sample circulation pipe (11), a drainage valve (16) is provided on the drainage pipe (15), and a circulation pump is provided on the first sand sample circulation pipe (10) and / or the second sand sample circulation pipe (11).

8. An on-line detection device for the quality of manufactured sand according to claim 7, characterized in that, The upper sieve (7) is rotatably arranged on the inner side wall of the sand sample circulation cylinder (3) through a rotary power-off spring reset device. When the rotary power-off spring reset device is powered on, the upper sieve (7) is in the first position, and when the rotary power-off spring reset device is powered off, the upper sieve (7) is in the second position.

9. An online detection method for the quality of manufactured sand, which applies the online detection device for the quality of manufactured sand described in claim 8, is characterized in that, It includes the following steps: S1: Cleaning: Open the first valve (4), the second valve (18) and the drain valve (16), and inject clear water from the feed port of the sample feed cylinder (1) to clean the equipment; S2: Close the first valve (4), the second valve (18) and the drain valve (16), and take a wet sand sample with a wet sand mass of m; S3: Fill water in the sample feed cylinder (1), and record the liquid volume V0 in the feed cylinder through the solution volume measurer (2); Add the wet sand into the sample feed cylinder (1) from the feed port, and record the liquid volume V1 in the feed cylinder; Calculate the moisture content θ by the specific gravity method: m = V s ρ s + V w ρ w ΔV = V s +V w ΔV = V1 - V0 m = V w ρ w +(ΔV - V w )ρ s = ΔVρ s + V w (ρ w - ρ s ) Where: m: mass of wet sand, g; V s : Volume of medium sand in wet sand, cm 3 ; V w : Volume of water in wet sand, cm 3 ; ρ s : saturated surface-dry density of sand, g / cm 3 ; ρ w : Density of water, g / cm 3 ; V0: The volume of the liquid added into the wet sand feed hopper, cm 3 ; V1: The volume of the liquid in the feed cylinder after adding wet sand, cm 3 ; m s : mass of sand in the sampled wet sand, g; θ: moisture content of wet sand, %.

10. The on-line detection method for the quality of manufactured sand according to claim 9, characterized in that, It also includes the following steps: S4: Mix the wet sand and water in the sample feed cylinder (1) to form a sand sample. Open the first valve (4) and discharge the sand sample into the upper chamber; The upper sieve (7) and / or the lower sieve rotate to the first position so that the meshes of the upper sieve (7) and the lower sieve correspond. Start the vibrator in the inclined vibration base (8) to separate the stone powder and sand in the sand sample. The stone powder passes through the meshes of the upper sieve (7) and the lower sieve and enters the lower chamber, and the sand is intercepted in the upper chamber. The upper sieve (7) and / or the lower sieve rotate to the second position; S5: Turn on the first stirrer (5), measure the SS concentration in the lower chamber using the SS concentration measuring device (6), and calculate the stone powder content w p : m p = (0.9734SS 2 + 139.16SS + 24.044)V Where: SS: turbidity value of the lower chamber, mg / l; V: volume of the lower chamber, l; m p : mass of stone powder, g; w p : Stone powder content, %; S6: After the stone powder and sand are separated, the sand sample becomes a sand sample without stone powder. Start the second stirrer (9), the second valve (18) and the circulation pump, and the sand sample without stone powder circulates in the first sand sample circulation pipeline (10), the transparent chamber (12), the second sand sample circulation pipeline (11) and the upper chamber; S7: Turn on the light source (14) and the CCD image acquisition and analysis device (13), obtain the image information of the sand sample without stone powder in the transparent chamber (12), obtain the quantity and volume of the sand within the particle size range of D1 - D5 based on the image information of the sand sample without stone powder, and record the frequency (%) ν within the particle size range of D1 - D5 1- ν5; The particle size ranges (mm) of D1 - D5 are respectively: D1：4.75-2.36； D2：2.36-1.18； D3：1.18-0.6； D4：0.6-0.3； D5：0.3-0.15； Calculate the fineness modulus M x : Where, f1 = ν1(1 - w p ); f2 = ν2(1 - w p ); f3 = ν3(1 - w p ); f4 = ν4(1 - w p ); f5 = ν5(1 - w p ); f6 = w p .

Images