Nodular cast iron well lid and production device and production method thereof

Abstract

The invention discloses a nodular cast iron well lid and a production device and method thereof, and relates to the technical field of nodular cast iron well lids, the nodular cast iron well lid comprises a workbench, a fixed cylinder and a movable cylinder, and the fixed cylinder is located above the workbench; the movable cylinder is arranged in the fixed cylinder in a penetrating mode and is coaxially connected into the fixed cylinder in a sliding mode, a first stock bin and a second stock bin which are independent of each other are arranged at the positions, on the two sides of the movable cylinder, in the fixed cylinder respectively and used for containing lime or fine sand of different colors respectively, and the bottom end of the movable cylinder is connected with a detection ball in a rolling mode; a first discharging port and a second discharging port are formed in the bottoms of the inner side walls of the first bin and the second bin respectively, the first discharging port is located below the second discharging port, a first communicating port and a second communicating port are formed in the two side walls of the movable cylinder respectively, and when the movable cylinder slides up and down, the first communicating port communicates with the first discharging port, and the second communicating port communicates with the second discharging port. Or the second communicating port is communicated with the second discharging port. The method has the effect of improving the production efficiency of the nodular cast iron well lid.

Description

Technical Field

[0001] The present application relates to the technical field of ductile iron manhole covers, and in particular to a ductile iron manhole cover and a production device and a production method thereof. Background Art

[0002] A manhole cover is a cover used to cover underground facilities such as roads, sewers, and cable wells. It can protect these facilities from damage and prevent debris and garbage from falling in. It can also ensure the flatness of roads and sidewalks, prevent accidents between vehicles and pedestrians due to uneven road surfaces, and make it easy for staff to open it and enter the well for maintenance.

[0003] Ductile iron manhole cover is a type of ductile iron product. Compared with ordinary cast iron manhole covers, ductile iron manhole covers have higher toughness and plasticity, which can effectively improve the strength and durability of the manhole cover. At the same time, ductile iron manhole covers also have good corrosion resistance and can adapt well to various application environments.

[0004] The production of ductile iron manhole covers usually includes processes such as melting, pouring, cooling and forming, surface heat treatment, machining and quality inspection. In the quality inspection process, the cast ductile iron manhole covers will be inspected for quality, such as size, hardness, appearance, flatness, etc. Conventionally, the flatness inspection of the manhole covers is carried out by manually measuring the surface of the manhole covers one by one with a steel ruler. This inspection method is inefficient and will greatly increase the labor intensity of workers, which will affect the production efficiency of the manhole covers. Summary of the invention

[0005] In order to improve the situation where manual inspection of the flatness of manhole covers is inefficient and labor-intensive, which will affect the overall production efficiency of the manhole covers, the present application provides a ductile iron manhole cover and a production device and method thereof.

[0006] On the one hand, the present application provides a ductile iron manhole cover production device, which adopts the following technical solution: A ductile iron manhole cover production device, comprising A workbench, placed horizontally, for placing the manhole cover to be inspected; A fixed cylinder, located above the workbench; The movable cylinder is inserted and coaxially slidably connected in the fixed cylinder. The fixed cylinder is provided with a first material bin and a second material bin independent of each other on both sides of the movable cylinder. The first material bin and the second material bin are used to contain lime or fine sand of different colors respectively. The bottom end of the movable cylinder is connected with a detection ball in a rolling manner. The detection ball is used to contact the manhole cover to be detected. The first material bin and the second material bin are respectively provided with a first discharge port and a second discharge port at the bottom of their respective inner side walls, and the first discharge port is located below the second discharge port. The movable cylinder is respectively provided with a first connecting port and a second connecting port on both side walls, and when the movable cylinder slides up and down, the first connecting port is connected with the first discharge port, or the second connecting port is connected with the second discharge port, and a dropping port connected with the first connecting port and the second connecting port is provided at the bottom of the movable cylinder.

[0007] Optionally, a restoring member is provided inside the fixed cylinder, and the restoring member is vertically placed above the movable cylinder, with one end of the restoring member connected to the inner wall of the fixed cylinder, and the other end connected to the top of the movable cylinder.

[0008] Optionally, the outer wall of the movable cylinder is covered with a seal, and the outer wall of the seal is in close contact with the inner wall of the fixed cylinder, so as to fill the gap between the movable cylinder and the fixed cylinder to achieve a sealed connection.

[0009] Optionally, the bottom walls of the first silo and the second silo gradually slope downward toward the first discharge port and the second discharge port, respectively.

[0010] Optionally, a vertical detection rod is provided at the bottom of the movable cylinder, the detection ball is rollingly connected to the bottom of the detection rod, the outer diameter of the detection rod is smaller than the outer diameter of the movable cylinder, and the blanking port is opened close to the detection rod.

[0011] Optionally, a locking piece is horizontally penetrated through the side wall of the fixed cylinder, and the locking piece can move horizontally. When the locking piece moves, one end of the locking piece located in the fixed cylinder abuts against the bottom of the movable cylinder to limit the upward and downward movement of the movable cylinder.

[0012] Optionally, the locking member includes a locking bolt and a locking block, the locking bolt is penetrated and threadedly connected to the fixed cylinder, the locking block is located at one end of the locking bolt close to the moving cylinder, and is rotatably connected to the locking bolt, and a transition slope is provided on the top surface of the locking block close to the moving cylinder, and the transition slope gradually tilts downward in the direction close to the moving cylinder, and when the end of the locking block contacts the detection rod, the top surface of the locking block abuts against the bottom surface of the moving cylinder.

[0013] Optionally, a plurality of the fixed cylinders are provided, and the plurality of the fixed cylinders are used to be distributed at radial intervals along the manhole cover to be inspected. A support frame is provided on the top of the fixed cylinder, and the support frame is connected to all the fixed cylinders. The support frame is rotatably connected to the workbench to drive all the fixed cylinders to rotate around the center of the manhole cover to be inspected.

[0014] On the one hand, the present application provides a method for producing a ductile iron manhole cover, using the ductile iron manhole cover production device as described above to perform production inspection on the ductile iron manhole cover, comprising the following steps: S1: Place the ductile iron manhole cover to be inspected horizontally on the workbench, and lower all the fixing cylinders until all the inspection balls are in contact with the surface of the manhole cover to be inspected; S2: All the fixed cylinders rotate around the center of the manhole cover to be inspected at the same time, and the detection ball rolls along the surface of the manhole cover to be inspected; When the detection ball rolls to the flat area of ​​the manhole cover to be detected, the movable cylinder does not move relative to the fixed cylinder or the relative movement is small. At this time, the first connecting port is not connected to the first discharge port, and the second connecting port is not connected to the second discharge port. When the detection ball rolls to the area where the manhole cover to be detected is sunken, the movable cylinder moves downward relative to the fixed cylinder, the first connecting port is connected with the first discharge port, and the lime or fine sand in the first silo falls out from the discharge port of the movable cylinder; When the detection ball rolls to the convex area on the manhole cover to be detected, the movable cylinder moves upward relative to the fixed cylinder, the second connecting port is connected with the second discharge port, and the lime or fine sand in the second silo falls out from the discharge port of the movable cylinder; S3: During the rotation of the fixed cylinder, if there is no lime or fine sand on the surface of the manhole cover to be inspected, it indicates that the manhole cover to be inspected is flat; if there is lime or fine sand on the surface of the manhole cover to be inspected, the manhole cover area where the lime or fine sand appears is judged as sunken or convex according to the corresponding color of the lime or fine sand on the manhole cover.

[0015] On the one hand, the present application provides a ductile iron manhole cover, which is produced by a ductile iron manhole cover production method as described above, characterized in that, in terms of weight percentage, it is composed of: C: 3.1-3.45%; Si: 4.8-5.2%; Mo: 0.75-1.45%; P: 0.027-0.032%; S: 0.011-0.015%; Cr: 0.057-0.07%; Ni: 0.2-0.22%; and The balance of Fe.

[0016] In summary, the present application includes at least one of the following beneficial effects: 1. The manhole cover of the present invention is made of ductile iron alloy, and a certain percentage of silicon, molybdenum, nickel, etc. is added to the components of the cast iron alloy, which can significantly improve the corrosion resistance of the cast iron alloy, and at the same time can provide the manhole cover with higher strength and better machining performance, so that the produced manhole cover is of better quality and more environmentally friendly; 2. The ductile iron manhole cover production device of the present invention adopts a method in which a moving cylinder slides up and down in a fixed cylinder. The moving cylinder is equipped with a rolling detection ball through a detection rod at the bottom. During detection, the detection ball contacts the surface of the manhole cover, and the fixed cylinder drives the detection ball to move along the surface of the manhole cover through the detection rod, while the distance between the fixed cylinder and the manhole cover remains unchanged. When the detection ball moves along the surface of the manhole cover, it will roll itself, so that the detection ball always moves along the surface of the manhole cover. When the detection ball moves to a relatively flat surface of the manhole cover, the detection ball always rolls along the flat surface of the manhole cover, and the detection ball will not be displaced or the displacement is very small in the height direction. At this time, the moving cylinder will not be displaced or will be displaced very little in the vertical height direction, the first connecting port is not connected to the first discharge port, and the second connecting port is not connected to the second discharge port, so no lime or fine sand will fall from the moving cylinder; when the detection ball rolls to the area where the manhole cover to be detected is sunken or convex, the detection ball drives the moving cylinder to descend or rise through the detection rod, so the first connecting port is connected to the first discharge port, or the second connecting port is connected to the second discharge port. In both cases, lime or fine sand will fall from the moving cylinder to the surface of the manhole cover. Therefore, whether the manhole cover is flat can be judged from whether lime or fine sand appears on the manhole cover, without manual inspection one by one; 3. By filling the first silo and the second silo with lime or fine sand of different colors, and the first connecting port is opened at the bottom of the first silo, the second connecting port is opened at the bottom of the second silo, and the first connecting port is located below the second connecting port. Therefore, when the moving cylinder descends, the first connecting port is connected with the first discharge port, and when the moving cylinder rises, the second connecting port is connected with the second discharge port. That is, the color of the lime or fine sand falling on the manhole cover when the moving cylinder rises or descends is different. Therefore, it is possible to judge whether the manhole cover is sunken or convex by the color of the lime or fine sand appearing on the manhole cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram showing the overall structure of a manhole cover production device according to Example 2 of the present application; Figure 2 is a cross-sectional schematic diagram showing the internal structure of the fixed cylinder in Example 2 of the present application; Figure 3 yes Figure 2 An enlarged schematic diagram at A; Figure 4 This is a schematic diagram showing the working of the production device for detecting the sinking area of ​​the manhole cover in Example 2 of the present application; Figure 5 This is a schematic diagram of the working of the production device for detecting the convex area on the manhole cover in Example 2 of the present application.

[0018] Explanation of the reference numerals in the accompanying drawings: 1. Workbench; 11. Manhole cover; 12. Lifting rod; 13. First driving member; 14. Fixed frame; 15. Second driving member; 16. Support frame; 2. Fixed cylinder; 21. Detection channel; 22. First silo; 221. First discharge port; 23. Second silo; 231. Second discharge port; 3. Moving cylinder; 31. Detection rod; 32. Detection ball; 33. First connecting port; 34. Second connecting port; 35. Dropping port; 4. Return member; 5. Sealing member; 6. Locking member; 61. Locking bolt; 62. Locking block; 63. Transition slope. DETAILED DESCRIPTION

[0019] The following is combined with Figure 1-5 This application is described in further detail. Example 1

[0020] Example 1 of the present application discloses a ductile iron manhole cover comprising the following components in weight percentage: C: 3.1-3.45%, Si: 4.8-5.2%, Mo: 0.75-1.45%, P: 0.027-0.032%, S: 0.011-0.015%, Cr: 0.057-0.07%, Ni: 0.2-0.22%, and the remainder of Fe.

[0021] The manhole cover provided in Example 1 of the present application is made of ductile iron alloy, and a certain percentage of silicon, molybdenum, nickel, etc. is added to the original cast iron alloy components, for example, C: 3.25%, Si: 5%, Mo: 1.1%, P: 0.03%, S: 0.013%, Cr: 0.064%, Ni: 0.21%, and the rest is Fe. The ductile iron manhole cover provided in Example 1 of the present application has good corrosion resistance, and has higher strength, toughness and better machining performance, so that the produced manhole cover has better quality, and less chromium is added, so it is more environmentally friendly. Example 2

[0022] Embodiment 2 of the present application discloses a ductile iron manhole cover production device, referring to Figure 1 The ductile iron manhole cover production device includes a horizontally placed workbench 1, and the manhole cover 11 to be inspected is horizontally placed on the table top of the workbench 1. A clamp or a positioning block for fixing the position of the manhole cover 11 can be set on the workbench 1, so that the manhole cover 11 can always remain stable and horizontally placed during the production and inspection process.

[0023] A vertical lifting rod 12 is also provided on the workbench 1. The lifting rod 12 is located on one side of the manhole cover 11. A first driving member 13 is provided at the bottom of the lifting rod 12. The first driving member 13 can be a vertically placed hydraulic cylinder. The first driving member 13 is fixed on the top surface of the workbench 1, and the output shaft of the first driving member 13 is vertically upward and coaxially fixed with the lifting rod 12, so that the first driving member 13 can drive the lifting rod 12 to move up and down in the vertical direction. A horizontal fixing frame 14 is fixedly connected to the top of the lifting rod 12. One end of the fixing frame 14 extends above the manhole cover 11. A second driving member 15 is fixed to the bottom of the fixing frame 14 at a position corresponding to the manhole cover 11. The second driving member 15 can be a servo motor. The output shaft of the second driving member 15 is vertically downward and fixedly connected to a horizontal support frame 16. A plurality of fixed cylinders 2 are provided at the bottom of the support frame 16. Each fixed cylinder 2 is placed vertically. The distance between each fixed cylinder 2 and the center of the manhole cover 11 is different. The fixed cylinders 2 extend along the radial direction of the manhole cover 11 and are distributed at intervals.

[0024] When the manhole cover 11 to be inspected is placed on the workbench 1, the first driving member 13 drives the fixing frame 14 to be lifted and lowered in the vertical direction through the lifting rod 12, and the fixing frame 14 drives the second driving member 15 to be lifted and lowered, and the second driving member 15 drives all the fixing cylinders 2 to be lifted and lowered through the supporting frame 16, and finally the second driving member 15 drives all the fixing cylinders 2 to rotate around the central axis of the manhole cover 11 through the supporting frame 16. In the embodiment of the present application, the number of fixing cylinders 2 is set to three, and in other embodiments, the number of fixing cylinders 2 can be increased or decreased according to the actual diameter of the manhole cover 11, so that the rotating fixing cylinders 2 can cover most areas of the manhole cover 11 as much as possible.

[0025] Reference Figure 1 and Figure 2 In order to detect the flatness of the surface of the manhole cover 11, a detection channel 21 is coaxially opened inside the fixed cylinder 2, and the detection channel 21 penetrates downwardly through the bottom surface of the fixed cylinder 2. A vertical moving cylinder 3 is arranged inside the fixed cylinder 2. The moving cylinder 3 is vertically slidably connected in the detection channel 21, and the bottom of the moving cylinder 3 can slide out of the bottom of the fixed cylinder 2 through the detection channel 21.

[0026] A vertical detection rod 31 is coaxially fixed at the bottom of the moving cylinder 3. The outer diameter of the detection rod 31 is smaller than the outer diameter of the moving cylinder 3. The detection rod 31 extends vertically downward, and a detection ball 32 is rollingly connected to the bottom surface of the detection rod 31. The detection ball 32 is used to contact the surface of the manhole cover 11, so that the fixed cylinder 2 drives the detection ball 32 to roll along the surface of the manhole cover 11 through the moving cylinder 3.

[0027] Since the height of the fixed cylinder 2 is fixed, in the process of driving the detection ball 32 to move along the surface of the manhole cover 11, when the detection ball 32 moves to the uneven surface of the manhole cover 11, the detection ball 32 will rise or fall along the surface of the manhole cover 11. In this process, the rising or falling detection ball 32 drives the movable cylinder 3 to rise or fall relative to the fixed cylinder 2 in the detection channel 21 through the detection rod 31.

[0028] In order to keep the detection ball 32 in contact with the surface of the manhole cover 11 during detection, a return member 4 is provided inside the fixed cylinder 2. The return member 4 can be a compression spring. The return member 4 is vertically placed above the moving cylinder 3, and the top of the return member 4 is fixedly connected to the inner wall of the fixed cylinder 2, and the bottom is fixedly connected to the top of the moving cylinder 3. When the detection rod 31 is connected to the moving cylinder 3 and moves downward as a whole, the return member 4 can pull the moving cylinder 3 to prevent the moving cylinder 3 from falling out of the fixed cylinder 2; when the detection rod 31 is connected to the moving cylinder 3 and moves upward as a whole, the moving cylinder 3 compresses the return member 4, and the return member 4 generates a downward return force, which drives the detection ball 32 to always be close to the surface of the manhole cover 11 through the moving cylinder 3 and the detection rod 31. In this process, the return member 4 is stretched or compressed, which can play a buffering role.

[0029] Reference Figure 2 In order to further facilitate the judgment of the flatness of the surface of the manhole cover 11, a first material bin 22 and a second material bin 23 are independently provided on both sides of the movable cylinder 3 inside the fixed cylinder 2. The first material bin 22 and the second material bin 23 surround the movable cylinder 3 from both sides to form a detection channel 21. The first material bin 22 and the second material bin 23 can be symmetrically distributed relative to one of the diameters of the fixed cylinder 2, and the first material bin 22 and the second material bin 23 are respectively used to contain lime or fine sand of different colors.

[0030] The first silo 22 and the second silo 23 are respectively provided with a first discharge port 221 and a second discharge port 231 at the bottom of their respective inner side walls, and in the vertical direction, the first discharge port 221 is provided below the second discharge port 231, and the lime or fine sand contained in the first silo 22 and the second silo 23 can fall out from the first discharge port 221 and the second discharge port 231 respectively by their own gravity. The detection sensitivity of the production device can be determined by controlling the opening positions of the first discharge port 221 and the second discharge port 231. For example, if the allowable error of the surface flatness of the manhole cover 11 is small, the spacing between the first discharge port 221 and the second discharge port 231 can be relatively reduced; otherwise, the spacing between the first discharge port 221 and the second discharge port 231 can be relatively increased.

[0031] To facilitate the falling of the lime or fine sand in the silo, the bottom walls of the first silo 22 and the second silo 23 are gradually inclined downward toward the first discharge port 221 and the second discharge port 231, respectively, that is, the bottom walls of the first silo 22 and the second silo 23 are gradually inclined downward toward the direction close to the moving cylinder 3. The downwardly inclined bottom walls are more conducive to the lime or fine sand sliding out of the corresponding silo under its own gravity.

[0032] Correspondingly, the moving cylinder 3 is provided with a first communication port 33 and a second communication port 34 on both side walls, wherein the first communication port 33 corresponds to the first material bin 22, and the second communication port 34 corresponds to the second material bin 23. In the vertical direction, the first communication port 33 is provided below the second communication port 34, and the distance between the first discharge port 221 and the second discharge port 231 is greater than the distance between the first communication port 33 and the second communication port 34, so that there is a section during the upward and downward sliding process of the moving cylinder 3, in which the first communication port 33 is not connected with the first discharge port 221, and the second communication port 34 is not connected with the second discharge port 231.

[0033] Reference Figures 2 to 5 The moving cylinder 3 slides up and down in the detection channel 21. When the moving cylinder 3 slides down to the first connecting port 33 and is connected to the first discharge port 221, the lime or fine sand contained in the first silo 22 falls into the moving cylinder 3 along the connected first discharge port 221 and the first connecting port 33; when the moving cylinder 3 slides up to the second connecting port 34 and is connected to the second discharge port 231, the lime or fine sand contained in the second silo 23 falls into the moving cylinder 3 along the connected second discharge port 231 and the second connecting port.

[0034] The bottom of the moving cylinder 3 is penetrated by a feeding port 35 corresponding to the first connecting port 33 and the second connecting port 34 respectively. The feeding port 35 can be a funnel shape that gradually shrinks downward. The feeding port 35 is opened around and close to the outer circle of the detection rod 31, so that the fine sand falling from the first silo 22 or the second silo 23 into the moving cylinder 3 can continue to fall from the feeding port 35 respectively, and finally fall to the uneven surface position of the manhole cover 11.

[0035] In order to prevent lime or fine sand from falling from the gap between the moving cylinder 3 and the fixed cylinder 2, the outer wall of the moving cylinder 3 is covered with a seal 5, which can be a rubber seal ring, and the seal 5 has openings at positions corresponding to the first communication port 33 and the second communication port 34, so as to keep the first communication port 33 and the second communication port 34 unobstructed. The outer wall of the seal 5 is in close contact with the inner wall of the fixed cylinder 2, so that the seal 5 can fill the gap between the moving cylinder 3 and the fixed cylinder 2 to achieve a sealed connection.

[0036] Reference Figure 2 and Figure 3In order to prevent the lime or fine sand inside the fixed cylinder 2 from falling out when not in use, a locking member 6 is horizontally penetrated on the side wall of the fixed cylinder 2 near the bottom end, and the locking member 6 includes a locking bolt 61 and a locking block 62, wherein the locking bolt 61 is penetrated and threadedly connected to the fixed cylinder 2, and the locking block 62 is located at the end of the locking bolt 61 near the moving cylinder 3 and is rotatably connected to the locking bolt 61. When an external force is applied to twist the locking bolt 61, the locking bolt 61 will drive the locking block 62 to move toward or away from the detection rod 31.

[0037] The top surface of the locking block 62 near the position of the moving cylinder 3 is provided with a transition slope 63, and the transition slope 63 gradually tilts downward in the direction close to the moving cylinder 3. When the end of the locking block 62 contacts the detection rod 31, the top surface of the locking block 62 abuts against the bottom surface of the moving cylinder 3, thereby achieving the purpose of locking the moving cylinder 3. When the moving cylinder 3 needs to be locked, the locking block 62 moves close to the moving cylinder 3, and the transition slope 63 contacts the bottom of the moving cylinder 3. When the locking block 62 moves horizontally, the transition slope 63 is used to drive the moving cylinder 3 to rise until the top surface of the locking block 62 abuts against the bottom surface of the moving cylinder 3. At this time, the first connecting port 33 is not connected to the first discharge port 221, and the second connecting port 34 is not connected to the second discharge port 231.

[0038] Reference Figures 2 to 5 During the detection, the detection ball 32 contacts the surface of the manhole cover 11, and the fixed cylinder 2 drives the detection ball 32 to move along the surface of the manhole cover 11, while the distance between the fixed cylinder 2 and the manhole cover 11 remains unchanged. When the detection ball 32 moves to a relatively flat surface of the manhole cover 11 (such as Figure 2 ), at this time, the detection ball 32 always rolls along the flat surface of the manhole cover 11, and the detection ball 32 does not move or moves very little in the height direction. At this time, the moving cylinder 3 also does not move or moves very little in the vertical height direction. The first connecting port 33 is not connected to the first discharge port 221, and the second connecting port 34 is not connected to the second discharge port 231. No lime or fine sand falls from the moving cylinder 3. When the detection ball 32 rolls to the sunken or convex area of ​​the manhole cover 11 to be detected (such as Figure 4 , Figure 5 ), the detection ball 32 drives the moving cylinder 3 to descend or ascend correspondingly through the detection rod 31. When the moving cylinder 3 descends to the first connecting port 33 and is connected to the first discharge port 221, or when the moving cylinder 3 ascends to the second connecting port 34 and is connected to the second discharge port 231, both cases will cause lime or fine sand to fall from the moving cylinder 3 to the surface of the manhole cover 11. Therefore, whether the manhole cover 11 is flat can be judged from whether lime or fine sand appears on the manhole cover 11, without manual inspection one by one, effectively reducing the labor intensity of workers.

[0039] At the same time, since the lime or fine sand in the first silo 22 and the second silo 23 are of different colors, when the moving cylinder 3 descends, the first connecting port 33 is connected to the first discharge port 221, and the lime or fine sand in the first silo 22 falls down; and when the moving cylinder 3 rises, the second connecting port 34 is connected to the second discharge port 231, and the lime or fine sand in the second silo 23 falls down, and the two different colors of lime or fine sand can directly fall to the corresponding sunken or convex positions on the manhole cover 11. That is, the colors of the lime or fine sand falling on the manhole cover 11 are different when the moving cylinder 3 rises or falls, so it can be judged whether the manhole cover 11 is sunken or convex by the color of the lime or fine sand on the manhole cover 11, and it can also be directly observed which specific areas on the manhole cover 11 are uneven.

[0040] The implementation principle of a ductile iron manhole cover production device in Example 2 of the present application is as follows: the detection ball 32 rolls along the surface of the manhole cover 11. When the detection ball 32 moves to a position where a depression or convexity appears on the surface of the manhole cover 11, the moving cylinder 3 will follow the detection ball 32 to descend or rise. If the moving cylinder 3 descends to the point where the first connecting port 33 is connected to the first discharge port 221, the lime or fine sand in the first silo 22 will fall from the drop port 35 to the corresponding depressed position of the manhole cover 11; if the moving cylinder 3 rises to the point where the second connecting port 34 is connected to the second discharge port 231, the lime or fine sand in the second silo 23 will fall from the drop port 35 to the corresponding convex position of the manhole cover 11. Therefore, whether the manhole cover 11 is flat can be judged by observing whether lime or fine sand appears on the surface of the manhole cover 11. Also, it is possible to judge which areas of the manhole cover 11 are convex or depressed by observing what color of lime or fine sand appears on the surface of the manhole cover 11. Example 3

[0041] Embodiment 3 of the present application discloses a method for producing a ductile iron manhole cover, which uses the ductile iron manhole cover production device in Embodiment 2 to perform production inspection on the ductile iron manhole cover, including the following steps: S1: Place the ductile iron manhole cover 11 to be inspected horizontally on the workbench 1, and lower all the fixing cylinders 2 until all the inspection balls 32 are in contact with the surface of the manhole cover 11 to be inspected; S2: All the fixed cylinders 2 rotate around the center of the manhole cover 11 to be inspected at the same time, and the detection ball 32 rolls along the surface of the manhole cover 11 to be inspected; When the detection ball 32 rolls to the flat area of ​​the manhole cover 11 to be detected, the movable cylinder 3 does not move relative to the fixed cylinder 2 or moves relatively little. At this time, the first connecting port 33 is not connected to the first discharge port 221, and the second connecting port 34 is not connected to the second discharge port 231. When the detection ball 32 rolls to the area where the manhole cover 11 to be detected sinks, the movable cylinder 3 moves downward relative to the fixed cylinder 2, the first connecting port 33 is connected to the first discharge port 221, and the lime or fine sand in the first silo 22 falls out from the drop port 35 of the movable cylinder 3; When the detection ball 32 rolls to the convex area on the manhole cover 11 to be detected, the movable cylinder 3 moves upward relative to the fixed cylinder 2, the second connecting port 34 is connected with the second discharge port 231, and the lime or fine sand in the second silo 23 falls out from the drop port 35 of the movable cylinder 3; S3: During the rotation of the fixed cylinder 2, if there is no lime or fine sand on the surface of the manhole cover 11 to be inspected, it indicates that the manhole cover 11 to be inspected is flat; if there is lime or fine sand on the surface of the manhole cover 11 to be inspected, the area of ​​the manhole cover 11 where the lime or fine sand appears is judged as sunken or convex according to the color corresponding to the lime or fine sand on the manhole cover 11.

[0042] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A ductile iron manhole cover production device, characterized in that: include A workbench, placed horizontally, for placing the manhole cover to be inspected; A fixed cylinder, located above the workbench; The movable cylinder is inserted and coaxially slidably connected in the fixed cylinder. The fixed cylinder is provided with a first material bin and a second material bin independent of each other on both sides of the movable cylinder. The first material bin and the second material bin are used to contain lime or fine sand of different colors respectively. The bottom end of the movable cylinder is connected with a detection ball in a rolling manner. The detection ball is used to contact the manhole cover to be detected. The first material bin and the second material bin are respectively provided with a first discharge port and a second discharge port at the bottom of their respective inner side walls, and the first discharge port is located below the second discharge port. The movable cylinder is respectively provided with a first connecting port and a second connecting port on both side walls, and when the movable cylinder slides up and down, the first connecting port is connected with the first discharge port, or the second connecting port is connected with the second discharge port, and a dropping port connected with the first connecting port and the second connecting port is provided at the bottom of the movable cylinder.

2. The ductile iron manhole cover production device according to claim 1 is characterized in that: A return member is arranged inside the fixed cylinder, and the return member is vertically placed above the movable cylinder. One end of the return member is connected to the inner wall of the fixed cylinder, and the other end is connected to the top of the movable cylinder.

3. The ductile iron manhole cover production device according to claim 1 is characterized in that: The outer wall of the movable cylinder is covered with a sealing member, and the outer wall of the sealing member is in close contact with the inner wall of the fixed cylinder, so as to fill the gap between the movable cylinder and the fixed cylinder to achieve a sealed connection.

4. The ductile iron manhole cover production device according to claim 1, characterized in that: The bottom walls of the first silo and the second silo are gradually inclined downward toward the first discharge port and the second discharge port, respectively.

5. The ductile iron manhole cover production device according to claim 1, characterized in that: A vertical detection rod is arranged at the bottom of the moving cylinder, the detection ball is rollingly connected to the bottom of the detection rod, the outer diameter of the detection rod is smaller than the outer diameter of the moving cylinder, and the blanking port is opened close to the detection rod.

6. The ductile iron manhole cover production device according to claim 5, characterized in that: A locking piece is horizontally provided on the side wall of the fixed cylinder. The locking piece can move horizontally. When the locking piece moves, one end of the locking piece located in the fixed cylinder abuts against the bottom of the movable cylinder to limit the upward and downward movement of the movable cylinder.

7. The ductile iron manhole cover production device according to claim 6, characterized in that: The locking member includes a locking bolt and a locking block, the locking bolt is penetrated and threadedly connected to the fixed cylinder, the locking block is located at one end of the locking bolt close to the moving cylinder, and is rotatably connected to the locking bolt, and a transition slope is provided on the top surface of the locking block close to the moving cylinder, and the transition slope gradually tilts downward in the direction close to the moving cylinder, and when the end of the locking block contacts the detection rod, the top surface of the locking block abuts against the bottom surface of the moving cylinder.

8. The ductile iron manhole cover production device according to claim 1, characterized in that: There are multiple fixed cylinders, which are distributed at intervals along the radial direction of the manhole cover to be inspected. A support frame is provided on the top of the fixed cylinder, and the support frame is connected to all the fixed cylinders. The support frame is rotatably connected to the workbench to drive all the fixed cylinders to rotate around the center of the manhole cover to be inspected.

9. A method for producing a ductile iron manhole cover, characterized in that: Using the ductile iron manhole cover production device as described in any one of claims 1 to 8 to perform production inspection on the ductile iron manhole cover comprises the following steps: S1: Place the ductile iron manhole cover to be inspected horizontally on the workbench, and lower all the fixing cylinders until all the inspection balls are in contact with the surface of the manhole cover to be inspected; S2: All the fixed cylinders rotate around the center of the manhole cover to be inspected at the same time, and the detection ball rolls along the surface of the manhole cover to be inspected; When the detection ball rolls to the flat area of ​​the manhole cover to be detected, the movable cylinder does not move relative to the fixed cylinder or the relative movement is small. At this time, the first connecting port is not connected to the first discharge port, and the second connecting port is not connected to the second discharge port. When the detection ball rolls to the area where the manhole cover to be detected is sunken, the movable cylinder moves downward relative to the fixed cylinder, the first connecting port is connected with the first discharge port, and the lime or fine sand in the first silo falls out from the discharge port of the movable cylinder; When the detection ball rolls to the convex area on the manhole cover to be detected, the movable cylinder moves upward relative to the fixed cylinder, the second connecting port is connected with the second discharge port, and the lime or fine sand in the second silo falls out from the discharge port of the movable cylinder; S3: During the rotation of the fixed cylinder, if there is no lime or fine sand on the surface of the manhole cover to be inspected, it indicates that the manhole cover to be inspected is flat; if there is lime or fine sand on the surface of the manhole cover to be inspected, the manhole cover area where the lime or fine sand appears is judged as sunken or convex according to the corresponding color of the lime or fine sand on the manhole cover.

10. A ductile iron manhole cover produced by the method for producing a ductile iron manhole cover according to claim 9, characterized in that: In terms of weight percentage, its composition is: C：3.1-3.45％； Si: 4.8-5.2%; Mo: 0.75-1.45%; P：0.027-0.032％； S：0.011-0.015％； Cr：0.057-0.07％； Ni: 0.2-0.22%; and The balance of Fe.

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