A four-eccentric blind plate quick switching device

Abstract

This invention discloses a four-eccentric blind flange quick-change device, comprising: a lower valve body assembly, an upper valve body assembly, a sliding plate assembly, a four-eccentric synchronous clamping mechanism, a central positioning sliding guide mechanism, a drive mechanism, and a safety lock mechanism. The lower and upper valve body assemblies have essentially the same structure, with a flange on one side for docking with the flange of the installed pipeline, and a sealing surface on the other side. The sealing surfaces of the lower and upper valve body assemblies are installed opposite each other. The sliding plate assembly is located between the lower and upper valve body assemblies, with a through hole at the center of one section and the other section used to cut off the medium. The four-eccentric synchronous clamping mechanism clamps the lower and upper valve body assemblies; the central positioning sliding guide mechanism is located around the sliding plate assembly, ensuring that the working position of the sliding plate assembly is coaxially aligned and limited; the safety lock mechanism prevents accidental operation. This invention has the advantages of simple operation, good sealing performance, rapid switching, small size, and light weight.

Description

Technical Field

[0001] This patent relates to a four-eccentric blind flange quick switching device, and in particular to a blind flange device with strict control over installation dimensions and weight, belonging to the field of pipeline connection and disconnection technology. Background Technology

[0002] A blind flange device is a pipeline shut-off device used to completely isolate the production medium, preventing production disruptions or even accidents caused by incomplete valve closure. CN 114110191 A describes a blind flange device comprising a left valve body, a right valve body, a sliding plate with a sealing structure, an eccentric linkage actuator, and a drive mechanism. The sliding plate is half open and half solid; the eccentric linkage and drive mechanism allow for the opening and clamping of the sliding plate, switching between open and blind positions without removing the pipeline connection bolts. However, this invention has shortcomings: the pipeline flange and the flange with the sealing surface are connected by a section of pipeline without integrated machining; the presence of a pressure block and shaft in the middle area results in a large overall size and weight; and currently, the blind flange only serves to isolate and conduct the medium, limiting its functionality.

[0003] Currently, low-pressure operating conditions such as oil and gas valve devices, acetaldehyde recovery devices, atmospheric pressure storage tank devices, and maleic anhydride heat exchanger devices all have strict controls on the weight of blind flanges. If the weight of the blind flange is too heavy, it may put a heavy burden on the supporting pipelines in low-pressure operating conditions, making it impossible to put them into safe use. Summary of the Invention

[0004] The technical problem solved by the present invention is to overcome the shortcomings of the prior art and provide a four-eccentric blind plate quick switching device. The device uses a drive mechanism to drive a clamping mechanism to clamp or release the slide plate assembly, enabling it to quickly switch between the open end and the blind end, thereby achieving rapid isolation and connection of media under low-pressure conditions.

[0005] The technical solution of this invention is: a four-eccentric blind plate quick switching device, comprising: a lower valve body assembly, an upper valve body assembly, a slide plate assembly, a four-eccentric synchronous clamping mechanism, a center positioning sliding guide mechanism, a drive mechanism, and a safety lock mechanism; wherein:

[0006] The lower valve body assembly and the upper valve body assembly have the same shape and structure. The main body is a rectangular plate structure with a through hole in the middle. A flange is set on one side of the through hole to connect with the flange of the installed pipeline, and the other side is a sealing surface. The lower valve body assembly and the upper valve body assembly are installed with the sealing surface facing each other.

[0007] The slide plate assembly is located between the sealing surfaces of the lower valve body assembly and the upper valve body assembly and can slide. It is divided into two sections: one section has a through hole in the center, and the other section does not have a hollowed-out center, which is used to cut off the medium.

[0008] The four-eccentric synchronous clamping mechanism is located on both sides of the lower valve body assembly and the upper valve body assembly, and is used to clamp the lower valve body assembly and the upper valve body assembly.

[0009] The central positioning sliding guide mechanism is located around the slide plate assembly. It is used to make the working positions of the lower valve body assembly, the upper valve body assembly and the middle slide plate assembly coaxially aligned, and at the same time, it enables the slide plate assembly to slide and be positioned quickly along the predetermined track.

[0010] The drive mechanism is located on the four-eccentric synchronous clamping mechanism, which drives the four-eccentric synchronous clamping mechanism to clamp the lower valve body assembly and the upper valve body assembly.

[0011] The safety lock mechanism is fixed to one side of the four-eccentric synchronous clamping mechanism. When the lower valve body assembly and the upper valve body assembly are clamped, the safety lock mechanism can prevent the drive mechanism from operating and prevent misoperation.

[0012] Preferably, the lower valve body assembly includes a lower valve body and a lower pressure block, and the upper valve body assembly includes an upper valve body and an upper pressure block;

[0013] The through-hole of the lower valve body assembly has the same diameter as the tubular structure;

[0014] Four lower pressure blocks with through holes are set at the four corners of the rectangular plate structure of the lower valve body, and four upper pressure blocks with through holes are set at the four corners of the rectangular plate structure in the middle of the upper valve body. The axial direction of the through holes is perpendicular to the sliding direction of the slide plate assembly.

[0015] Preferably, the skateboard assembly includes a blind plate, a perforated plate, and a sealing ring, specifically:

[0016] The slide plate assembly has one half of the through hole as an orifice plate and the other half used to cut off the medium as a blind plate. The through hole size is the same as that of the lower valve body assembly and the upper valve body assembly.

[0017] The blind flange is only provided with a sealing ring groove with the same size as the through hole on the upper valve body assembly and the lower valve body assembly, and a sealing ring is installed in the sealing ring groove;

[0018] The blind plate and the orifice plate are connected together by a mounting pin. After removing the pin, the blind plate and the orifice plate can be used separately.

[0019] Preferably, the four-eccentric synchronous clamping mechanism includes: four eccentric shafts, four concentric shafts, and four shaft connecting rods. These structures ensure the clamping characteristics of the four-eccentric synchronous clamping mechanism, wherein:

[0020] Each eccentric shaft corresponds to a through hole in a lower pressure block. Each eccentric shaft is divided into four sections, each with a different shaft diameter, numbered from thickest to thinnest as section 1, section 2, section 3, and section 4. The section 1 of the eccentric shaft mates with the lower pressure block. The thickest section has a groove at its end for installing a retaining ring. The second section of the eccentric shaft has a pin hole.

[0021] Four concentric shafts pass through the through holes of the four upper pressure blocks respectively. The concentric shafts are divided into two sections. The thicker section of the concentric shaft mates with the upper pressure block. Grooves are provided at the ends of both the thicker and thinner sections for installing retaining rings.

[0022] The connecting rod is in the shape of a channel steel, with a through hole at each end. The diameter of one through hole is the same as the diameter of the second section of the eccentric shaft, and the size of the other through hole is the same as the thinner section of the concentric shaft. Each connecting rod connects a set of corresponding eccentric shafts and concentric shafts. The relative position of the concentric shaft and the upper valve body assembly is kept fixed by the action of the connecting rod, the upper pressure block, and the retaining rings at the end grooves of the thicker and thinner sections of the concentric shaft. The lower valve body assembly and the upper valve body assembly are connected by the eccentric shaft, the concentric shaft, and the connecting rod in the four-eccentric synchronous clamping mechanism. At the same time, the relative position of the first eccentric shaft, the second eccentric shaft, and the lower valve body assembly is kept fixed by the action of the pin and the retaining ring installed at the end of the thickest section of the shaft.

[0023] Preferably, the four-eccentric synchronous clamping mechanism further includes: a first crank, a second crank, two third cranks, a crankshaft welded to the cranks, two crank connecting rods, and a crank synchronous connecting rod, to ensure the synchronous characteristics of the four-eccentric synchronous clamping mechanism; wherein:

[0024] On one side parallel to the sliding direction of the sliding assembly, a first crank is connected to a shaft connecting rod, one end of which is connected to one end of the crank connecting rod via a crankshaft, and the other end of the crank connecting rod is connected to a third crank via a crankshaft. The third crank is connected to another shaft connecting rod on the same side.

[0025] The first crank has a through hole for welding the crankshaft, a through hole with keyways at both ends, a square hole, and a conventional through hole, the conventional through hole engaging with the second section of the corresponding eccentric shaft; one end of the drive mechanism is located in the square hole; the third crank has a through hole for welding the crankshaft and a conventional through hole, the conventional through hole engaging with the second section of the corresponding eccentric shaft.

[0026] Similarly, on the other side parallel to the sliding direction of the sliding component, the second crank is connected to a shaft connecting rod, one end of which is connected to one end of the crank connecting rod through a crankshaft, and the other end of the crank connecting rod is connected to the third crank through a crankshaft. The third crank is connected to another shaft connecting rod on the same side.

[0027] The second crank is provided with a through hole for welding the crankshaft, a through hole with keyways at both ends, and a conventional through hole that mates with the second section of the corresponding eccentric shaft. The third crank on this side is also provided with a through hole for welding the crankshaft and a conventional through hole that mates with the second section of the corresponding eccentric shaft.

[0028] The crank synchronizing connecting rod has four keyways at both ends and threaded holes on both end faces. The crank synchronizing connecting rod passes through the keyway through holes of the first and second cranks and is connected to the first and second cranks by a flat key. Both ends are fixed by screws fastening the shaft end retaining rings.

[0029] Preferably, the center positioning sliding guide mechanism includes a limiting plate, a flanged bushing, a valve body guide post, and a handle, specifically:

[0030] The limiting plate is fastened to both ends of the slide plate assembly with bolts. When the slide plate assembly slides to the position where the blind plate or perforated plate is concentric with the through holes of the lower valve body and the upper valve body, the limiting plate is attached to the side of the upper valve body to limit the extreme sliding of the slide plate assembly.

[0031] The flanged bushing is installed on the lower valve body and the upper valve body, parallel to both sides of the slide plate assembly, forming two slide rails. The flanged bushing restricts the sliding direction of the slide plate assembly.

[0032] One end of the valve body guide post is a smooth shaft, and the other end is threaded. It is located between the lower valve body and the upper valve body, parallel to the axial direction of the through hole of the lower valve body and the upper valve body, restricting the lower valve body and the upper valve body to move only along the axial direction of its upper through hole.

[0033] The handle is mounted on the limit plate and is used to push or pull the skateboard assembly.

[0034] Preferably, the drive mechanism is a square rod-shaped wrench with a bent end to fit into the square hole of the first crank. By rotating the wrench, the first crank is rotated, and then the four eccentric shafts are rotated synchronously through the combined action of the crank connecting rod and the crank synchronous connecting rod.

[0035] Of the two sides parallel to the sliding direction of the skateboard assembly, the eccentric shaft corresponding to the side of the wrench is designated as the first eccentric shaft, and the eccentric shaft on the opposite side is designated as the second eccentric shaft. The only difference between the first and second eccentric shafts is the angle between the center line of the pin hole used to connect the crank and the line connecting the centers of each segment of the eccentric shaft.

[0036] If the angle between the center line of the first eccentric shaft pin hole and the line connecting its segments is α, then the angle between the center line of the second eccentric shaft pin hole and the line connecting its segments is -α. This ensures that when the wrench rotates on one side, the direction and distance of displacement generated by the rotation of the first and second eccentric shafts on both sides are the same. The displacement is transmitted to the concentric shaft through the four shaft connecting rods, and the direction and distance of displacement are also the same. This causes the lower valve body and the upper valve body to move closer or further apart, thereby achieving the loosening and clamping of the slide plate assembly.

[0037] Preferably, the safety lock mechanism consists of a lock plate and a snap ring, and is mounted on the crank connecting rod near the third crank.

[0038] The locking plate has a notch, a through hole, and a threaded hole. A hexagonal headstock shoulder screw is used to pass through the through hole and mate with the threaded hole on the crank connecting rod. A knurled headstock screw is installed at the threaded hole of the locking plate. A flexible cylindrical pin is provided in the blind hole on the crank connecting rod near the locking plate. The two rings of the retaining spring are respectively fitted onto the hexagonal headstock shoulder screw and the flexible cylindrical pin on the crank connecting rod, and the other end abuts against the knurled headstock screw.

[0039] When the four-eccentric synchronous clamping mechanism clamps the skateboard assembly, the notch of the locking plate can engage the fourth segment of the eccentric shaft furthest from the wrench, thereby restricting the movement of the wrench. When releasing the skateboard assembly, the snap ring must be activated first so that the notch of the locking plate no longer engages the thinnest segment of the eccentric shaft before the wrench can be operated.

[0040] Compared with the prior art, the present invention has the following advantages:

[0041] (1) The present invention has made lightweight treatment of parts such as valve body, blind plate assembly, pressure block and shaft, making its structure more compact and reducing the overall size and weight, so that it can be applied to the use environment where there are strict requirements on the overall weight of the blind plate device.

[0042] (2) The present invention has made a special design for the four-eccentric synchronous clamping mechanism. Two short eccentric shafts are set at one end of the upper and lower valve body components, and two short eccentric shafts are also set at the same position at the other end. Under the action of the crank synchronous connecting rod, these four short eccentric shafts replace the function of the two long eccentric shafts of the traditional four-eccentric synchronous clamping mechanism. Through this design, the volume of the middle part of the long eccentric shaft can be avoided from conflicting with the position of the upper and lower valve body flanges, and there is no need to increase the valve body size and thus bring extra weight.

[0043] (3) The present invention features a special design for the slide plate assembly, which consists of a blind plate and a perforated plate. The slide plate assembly can be assembled together for easy and rapid plugging; it can also be used independently to reduce the overall weight of the device. Threaded holes are provided on the side of the blind plate to facilitate air source access and enable online detection and other applications. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the overall structure of the device of the present invention;

[0045] Figure 2 This is a front view of the overall structure of the device of the present invention;

[0046] Figure 3 This is a rear view of the overall structure of the device of the present invention;

[0047] Figure 4 This is a side view of the overall structure of the device of the present invention;

[0048] Figure 5This is a cross-sectional view of the overall structure of the device of the present invention;

[0049] Figure 6 (a) is a sectional view of the pin hole of the eccentric shaft; (b) is a sectional view of the pin hole of the first eccentric shaft;

[0050] Figure 7 This is a cross-sectional view of the skateboard assembly of the present invention. Detailed Implementation

[0051] The technical solution of this invention is:

[0052] A four-eccentric blind plate quick-change device includes upper and lower valve body assemblies, a slide plate assembly, a four-eccentric synchronous clamping mechanism, a central positioning sliding guide mechanism, a drive mechanism, and a safety lock mechanism. The upper valve body assembly consists of an upper valve body and an upper pressure block. The lower valve body assembly consists of a lower valve body and a lower pressure block. The slide plate assembly consists of a blind plate, a perforated plate, and sealing rings embedded in grooves on both sides of the blind plate and perforated plate. The blind plate has threaded holes on its side for easy air supply access, enabling online detection and other applications. The four-eccentric synchronous clamping mechanism consists of an eccentric shaft, a concentric shaft, a connecting rod, and a crank. Operating the drive mechanism allows the four-eccentric synchronous clamping mechanism to quickly clamp or release the slide plate assembly. The central positioning sliding guide mechanism consists of a valve body guide post, a flanged bushing, a limiting plate, and a handle. It ensures that the valve bodies on both sides and the blind plate or perforated plate in the middle are coaxially aligned, and that the slide plate assembly can quickly slide and be positioned along a predetermined track. The drive mechanism is a wrench. The safety lock device includes a locking plate and a snap ring.

[0053] The technical solutions for achieving the main functions are as follows:

[0054] (1) The present invention provides sealing ring grooves on both sides of the blind plate and the orifice plate. After the sealing ring is installed, the eccentric clamping mechanism is driven by the pull-out slide assembly and the operation drive mechanism to quickly clamp and release the blind plate assembly, which can realize the rapid connection and isolation of the medium.

[0055] (2) The upper and lower valve bodies of the present invention have basically the same shape. Both ends are tubular structures, and the middle part is a rectangular plate structure. The plate structure is provided with a through hole with the same diameter as the tubular structure. One side of the tubular structure is a pipe flange, which is connected to the flange of the process system pipe to be connected; the other side of the tubular structure is a middle flange with a sealing surface, which is clamped with the sliding plate assembly to form a sealing ring.

[0056] (3) The present invention has made a special design for the four-eccentric synchronous clamping mechanism. Two short eccentric shafts are set at one end of the upper and lower valve body components, and two short eccentric shafts are also set at the same position at the other end. Under the action of the crank synchronous connecting rod, these four short eccentric shafts replace the function of the two long eccentric shafts of the traditional blind plate quick switching device. Through this design, the volume of the middle part of the long eccentric shaft can be avoided from conflicting with the position of the upper and lower valve body flanges, and there is no need to increase the valve body size and thus bring extra weight.

[0057] (4) The blind plate and the perforated plate of the present invention can be assembled together or used separately. A portion of the cylinder is removed from the center of the blind plate, and a threaded hole is provided on its side with a through hole at the center of the threaded hole, connecting to the centrally hollowed-out portion to facilitate the connection of the air source and realize online detection and other uses.

[0058] (5) The process of clamping and releasing the slide plate assembly can be completed by only one operator, which effectively reduces time and labor costs.

[0059] like Figure 1 As shown, the device mainly consists of a lower valve body assembly 1, an upper valve body assembly 2, a slide plate assembly 3, a four-eccentric synchronous clamping mechanism 4, a center positioning sliding guide mechanism 5, a drive mechanism 6, and a safety lock mechanism 7.

[0060] The lower valve body assembly 1 and the upper valve body assembly 2 have basically the same shape and structure. One side is equipped with a flange to connect with the flange of the installed pipeline, and the other side is a sealing surface. The sealing surfaces of the lower valve body assembly 1 and the upper valve body assembly 2 are installed facing each other. The sliding plate assembly 3 is located between the sealing surfaces of the lower valve body assembly 1 and the upper valve body assembly 2. It can be divided into two sections. One section has a through hole in its center, and the center of the other section is partially removed but not completely hollowed out, which can serve as a medium cutoff function. The four-eccentric synchronous clamping mechanism 4 is located on both sides of the lower valve body assembly 1 and the upper valve body assembly 2, and is used to clamp the lower valve body assembly 1 and the upper valve body assembly 2. The center positioning sliding guide mechanism 5 is located around the slide plate assembly 3, which can ensure that the working positions of the lower valve body assembly 1, the upper valve body assembly 2 and the middle slide plate assembly 3 are coaxially aligned, and that the slide plate assembly 3 can slide and be positioned quickly along a predetermined track. The drive mechanism 6 is located at the edge of the four-eccentric synchronous clamping mechanism. In this invention, the drive mechanism 6 is a square bar wrench, which cooperates with the square hole of the four-eccentric synchronous clamping mechanism 4 to drive the four-eccentric synchronous clamping mechanism 4 to clamp the lower valve body assembly 1 and the upper valve body assembly 2. The safety lock mechanism 7 is fixed to one side of the four-eccentric synchronous clamping mechanism by screws and elastic cylindrical pins. When the lower valve body assembly 1 and the upper valve body assembly 2 are clamped, the safety lock mechanism 7 can lock the eccentric shaft. At this time, the drive mechanism 6 cannot be operated, which effectively prevents the occurrence of misoperation.

[0061] like Figure 1 and Figure 4As shown, the lower valve body assembly 1 includes a lower valve body 101 and a lower pressure block 102, and the upper valve body assembly 2 includes an upper valve body 201 and an upper pressure block 202. The lower valve body 101 and the upper valve body 201 have basically the same shape, with the main body being a rectangular plate structure. The rectangular plate structure has tubular structures on both sides. The plate structure has through holes with the same diameter as the tubular structures. One side of the tubular structure with the through hole is a pipe flange, connected to the flange of the process system pipeline; the other side of the tubular structure is a middle flange with a sealing surface. The pipe flange of the lower valve body 101 has through threaded holes at both ends. On the sealing surface side, the rectangular plate has four threaded holes with a depth equal to the thickness of the rectangular plate. The pipe flange of the upper valve body 201 has through holes at both ends. On the sealing surface side, the rectangular plate has eight threaded holes with a depth equal to the thickness of the rectangular plate. Four lower pressure blocks 102 with through holes are welded to the four corners of the rectangular plate structure of the lower valve body 101. Four upper pressure blocks 202 with through holes are welded to the four corners of the rectangular plate structure in the middle of the upper valve body 201. The axial direction of the through holes on the pressure blocks is perpendicular to the sliding direction of the slide plate assembly 3.

[0062] like Figure 7 As shown, the slide plate assembly 3 includes a blind plate 301, a perforated plate 302, and a sealing ring 303. The perforated plate 302 has a through hole of the same diameter as the tubular structure of the upper valve body 101 and the lower valve body at its middle position. A sealing ring groove is provided at the edge of the through hole, and a sealing ring is installed in the sealing ring groove. The blind plate 301 has only a sealing ring groove of the same diameter as the tubular structure of the upper valve body assembly and the lower valve body assembly at its middle position, and a sealing ring is installed in the sealing ring groove. The blind plate 301 and the perforated plate 302 are connected together by a mounting pin. After the pin is removed, the blind plate 301 and the perforated plate 302 can be used independently.

[0063] like Figure 2 and Figure 3As shown, the four-eccentric synchronous clamping mechanism 4 includes a first eccentric shaft 401, a second eccentric shaft 402, a concentric shaft 403, a shaft connecting rod 404, a first crank 405, a second crank 406, a third crank 407, a crank shaft 408 welded to the crank, a crank connecting rod 409, and a crank synchronous connecting rod 410. For the lower valve body assembly 1, it has two symmetrical planes; the symmetrical plane perpendicular to the through hole direction of the lower pressure block 102 is selected as the reference plane. The reference plane divides the lower valve body assembly 1 into two sides. The drive mechanism 6, in this device, is a wrench 601, which can be located on either side. On the side where the wrench 601 is located, the first eccentric shaft 401, closer to the wrench, passes through the through hole of the lower pressure block 102, and the first eccentric shaft 401, farther from the wrench, also passes through the through hole of the lower pressure block 102. On the opposite side of the wrench 601, the second eccentric shaft 402, closer to the wrench, passes through the through hole of the lower pressure block 102, and the second eccentric shaft 402, farther from the wrench, also passes through the through hole of the lower pressure block 102. The first eccentric shaft 401 and the second eccentric shaft 402 are divided into four sections, each with a different shaft diameter. The thickest section of the first eccentric shaft 401 and the second eccentric shaft 402 mates with the lower pressure block 102. The end of the thickest section has a groove for installing a retaining ring. The second thickest sections of the first eccentric shaft 401 and the second eccentric shaft 402 are provided with pin holes. The only difference between the two is the angle between the center line of the pin hole used to connect the crank and the line connecting the centers of the different sections of the eccentric shaft. Otherwise, they are identical.

[0064] Four concentric shafts 403 pass through the through holes of the four upper pressure blocks respectively. The concentric shafts 403 are divided into two sections. The thicker section of the concentric shaft 403 cooperates with the upper pressure block 202. Grooves are provided at the ends of both the thicker and thinner sections, so that retaining rings can be installed.

[0065] The shaft connecting rod 404 is shaped like a channel steel, with a through hole at each end. One through hole is the same size as the thicker section of the first eccentric shaft 401 and the second eccentric shaft 402, and the other through hole is the same size as the thinner section of the concentric shaft 403. The through holes of the four shaft connecting rods 404 connect to: the first eccentric shaft 401 and the concentric shaft 403 near the wrench, the first eccentric shaft 401 and the concentric shaft 403 away from the wrench, the second eccentric shaft 401 and the concentric shaft 403 near the wrench, and the second eccentric shaft 401 and the concentric shaft 403 away from the wrench, respectively. Through the action of the shaft connecting rods 404, the upper pressure block 202, and the retaining rings at the end grooves of the thicker and thinner sections of the concentric shaft 403, the relative position of the concentric shaft 403 and the upper valve body assembly 2 is kept fixed. The lower valve body assembly 1 and the upper valve body assembly 2 are connected by the first eccentric shaft 401, the second eccentric shaft 402, the concentric shaft 403 and the shaft connecting rod 404 in the four eccentric synchronous clamping mechanism 4.

[0066] like Figure 2 , Figure 3 , Figure 4 , Figure 5 The first crank 405 shown has a through hole for welding the crankshaft 408, a through hole with keyways at both ends, a square hole, and a conventional through hole; the second crank 406 has a through hole for welding the crankshaft 408, a through hole with keyways at both ends, and a conventional through hole; the third crank 407 has a through hole for welding the crankshaft 408 and a conventional through hole. All three cranks 405, 406, and 407 are drilled from the side to form a pin hole, the axis of which intersects perpendicularly with the axis of the conventional through hole. In this design, the conventional through hole of the first crank 405 mates with the second thicker section of the first eccentric shaft 401 near the wrench; the conventional through hole of the second crank 406 mates with the second thicker section of the second eccentric shaft 402 near the wrench; the conventional through hole of the third crank 407 on one side of the wrench 601 mates with the second thicker section of the first eccentric shaft 401 away from the wrench 601; and the conventional through hole of the third crank 407 on the opposite side of the wrench 601 mates with the second thicker section of the second eccentric shaft 402 away from the wrench 601. Four pins are used, passing through the pin holes of the cranks and shafts, to keep their axial relative positions fixed. The relative positions of the first eccentric shaft 401, the second eccentric shaft 402, and the lower valve body assembly 1 are kept fixed by the action of retaining rings installed at the thickest ends of the pins and shafts. The cranks and crank shafts can also be integral; in this invention, all welded components can be integrally formed.

[0067] The device contains two crank connecting rods 409, each with through holes at both ends, as well as a blind hole and a bolt hole. The two through holes of one crank connecting rod 409 mate with the crankshaft 408 welded to the first crank 405 and the third crank 407 on the wrench side, respectively. The rectangular protrusion on the crank connecting rod 409 is close to the first crank 405 and faces downwards. A flexible cylindrical pin is installed in the blind hole of this crank connecting rod 409. The two through holes of the other crank connecting rod 409 mate with the crankshaft 408 welded to the second crank 406 and the third crank 407 on the opposite side of the wrench, respectively. The rectangular protrusion is close to the second crank 406 and faces downwards. The crank synchronizing connecting rod 410 has four keyways at both ends and threaded holes on both end faces. The crank synchronization connecting rod 410 passes through the keyway through the first crank 405 and the second crank 406, and is connected to the first crank 405 and the second crank 406 by a flat key. Both ends are fixed by screws fastening the shaft end retaining rings.

[0068] like Figure 2As shown, the center positioning sliding guide mechanism 5 includes a limiting plate 501, a flanged bushing 502, a valve body guide post 503, and a handle 504. The limiting plate 501 is fastened to both ends of the slide plate assembly 3 by bolts. When the slide plate assembly 3 slides to the position where the blind plate 301 or the perforated plate 302 is concentric with the lower valve body 101 and the upper valve body 201, the limiting plate 501 is attached to the side of the upper valve body 201, limiting the extreme sliding position of the slide plate assembly 3. The flanged bushing 502 is installed at the threaded holes of the rectangular plates of the lower valve body 101 and the upper valve body 201 by bolts and nuts, forming two slide rails. The flange restricts the axial position of the slide plate assembly 3, positioning the slide plate assembly 3 in the middle of the sealing surfaces of the middle flanges of the lower valve body 101 and the upper valve body 201. One end of the valve body guide post 503 is a smooth shaft, and the other end is threaded. It is engaged with the threaded hole of the lower valve body 101 and the through hole of the upper valve body 201 respectively. It is located between the lower valve body 101 and the upper valve body 201, parallel to the axial direction of the inner hole of the lower valve body 101 and the upper valve body 201, restricting the lower valve body 101 and the upper valve body 201 to move only along the axial direction. The handle 504 is installed on the limit plate 501, which can push or pull the slide plate assembly 3. The design of the center positioning sliding guide mechanism 5 can ensure that the lower valve body 101, the upper valve body 201 and the blind plate 301 or the perforated plate 302 are coaxially aligned. During the push and pull operation, the slide plate assembly 3 can slide quickly and accurately along the predetermined track.

[0069] like Figure 1 As shown, the drive mechanism 6 in this device is a wrench 601. The wrench 601 is a square rod with a bent end that engages with the square hole of the first crank 405. Rotating the wrench rotates the first crank 405. Through the combined action of the crank connecting rod 409 and the crank synchronous connecting rod 410, the first eccentric shaft 401 near the wrench, the first eccentric shaft 401 away from the wrench, the second eccentric shaft 402 near the wrench, and the second eccentric shaft 402 away from the wrench rotate synchronously. The difference between the first eccentric shaft 401 and the second eccentric shaft 402 lies only in the angle between the center line of the pin hole used to connect the crank and the line connecting the centers of the different segments of the eccentric shaft. Figure 6 As shown, if the angle between the center line of the pin hole of the first eccentric shaft 401 and the line connecting the centers of each segment of the eccentric shaft is α, then the angle between the center line of the pin hole of the second eccentric shaft 402 and the line connecting the centers of each segment of the eccentric shaft is -α. With this design, it can be ensured that when the wrench 601 rotates on one side, the direction and distance of displacement generated by the rotation of the first eccentric shaft 401 and the second eccentric shaft 402 on both sides are the same. The direction and distance of displacement transmitted to the concentric shaft 403 through the four shaft connecting rods 404 are also the same, thereby causing the lower valve body 101 and the upper valve body 201 to move closer or further away from each other, realizing the loosening and clamping of the slide assembly 3.

[0070] like Figure 2As shown, the safety locking mechanism 7 consists of a locking plate 701 and a retaining ring 702. The locking plate 701 has a notch, a through hole, and a threaded hole. A hexagonal headstock shoulder screw passes through the through hole and mates with the threaded hole on the crank connecting rod 409. A knurled headstock screw is installed at the threaded hole of the locking plate 701. The two rings of the retaining ring 702 are respectively fitted onto the hexagonal headstock shoulder screw and the elastic cylindrical pin on the crank connecting rod, while the other end abuts against the knurled headstock screw. When the four-eccentric synchronous clamping mechanism 4 clamps the slide plate assembly 3, the notch of the locking plate 701 can engage the thinnest section of the first eccentric shaft 401, which is farthest from the wrench, thereby restricting the movement of the wrench 601, preventing it from being operated, preventing accidental operation, and ensuring safety. When it is necessary to release the skateboard assembly 3, the snap ring 702 must be moved first to prevent the notch of the locking plate 701 from engaging the thinnest part of the first eccentric shaft 401, which is far from the wrench, before the wrench 601 can be operated.

[0071] When the medium is in a connected state, the four-eccentric synchronous clamping mechanism 4 clamps the orifice plate 302 to form a seal. When it is necessary to isolate the medium, the blind plate 301 and the orifice plate 302 can be assembled together by installing the pin. Then, the snap ring 702 is moved first to prevent the notch of the locking plate 701 from locking the thinnest section of the first eccentric shaft 401 away from the wrench. Then, the wrench 601 is operated counterclockwise to drive the four-eccentric synchronous clamping mechanism 4, so that the lower valve body 101 and the upper valve body 201 move away from each other, releasing the slide plate assembly 3. When the four-eccentric synchronous clamping mechanism 4 completes the release step, the slide plate assembly 3 is smoothly moved in a direction perpendicular to the pipeline under the guidance of the flanged bushing 502 by pushing and pulling the handle 504. The movement of the slide plate assembly 3 moves the orifice plate 302 out, along with the blind plate 301, until the limiting plate 501 of the blind plate 301 is attached to the side of the upper valve body 201. At this time, it indicates that the blind plate 301 has moved to the correct position. Turning the wrench 601 clockwise drives the four blind plates 301 of the four-eccentric synchronous clamping mechanism to clamp and form a seal, thus achieving media isolation.

[0072] like Figure 5 and Figure 7 As shown, a portion of a cylinder is removed from the center of the blind flange 301. The diameter of the cylinder is the same as the diameter of the through hole, and the height of the cylinder determines the thickness of the thinnest part of the blind flange, which only needs to meet the strength requirements. Threaded holes are provided on the side of the blind flange 301, and a through hole is provided at the center of each threaded hole, which directly connects to the hollowed-out part in the center of the blind flange, facilitating the connection of the air source and enabling online detection and other applications.

[0073] The sealing ring 303 in this invention can also be a spiral wound gasket, sealing block, non-metallic gasket, metallic gasket, or other sealing components such as a combination of double seals.

[0074] The attached diagram is labeled as follows: 1-lower valve body assembly, 2-upper valve body assembly, 3-slide plate assembly, 4-eccentric parallel linkage clamping mechanism, 5-center positioning sliding guide mechanism, 6-drive mechanism, 7-safety lock mechanism;

[0075] 101-Lower valve body, 102-Lower pressure block, 201-Upper valve body, 202-Upper pressure block, 301-Blind plate, 302-Orifice plate; 303-Sealing ring, 401-First eccentric shaft, 402-Second eccentric shaft, 403-Concentric shaft, 404-Shaft connecting rod, 405-First crank, 406-Second crank, 407-Third crank, 408-Crankshaft, 409-Crank connecting rod, 410-Crank synchronous connecting rod, 501-Limiting plate, 502-Flanged bushing, 503-Valve body guide post, 504-Handle, 601-Wrench, 701-Lock plate, 702-Snap ring;

[0076] Taking an atmospheric pressure storage tank as a typical application example, the device involved in this invention is installed between the tank top flange and the breather valve of the atmospheric pressure storage tank, enabling rapid isolation between the tank and the breather valve. The device is equipped with an interface for connecting testing instruments and a testing gas source. After isolation, connecting a portable breather valve testing device enables online testing of the breather valve. Compared with traditional offline testing methods for breather valves, this reduces the processes of hoisting, disassembling, transporting, and returning the breather valve for hoisting and installation, offering significant advantages in safety, convenience, environmental friendliness, and economy, with even more pronounced advantages in large-scale testing. Compared with online testing methods with a detection auxiliary valve, this reduces the isolation time of the breather valve from tens of minutes to only 3-5 seconds, greatly reducing the time for the medium inside the atmospheric pressure storage tank to leak into the atmosphere, providing a significant safety advantage and representing the best solution to meet the compliance requirements of annual breather valve inspection. Therefore, it is necessary to provide a lightweight blind flange device that can quickly switch between pipeline conduction and blind sealing states while also possessing online testing capabilities, to meet the current requirements of industrial pipelines for lighter, smaller, and more functional blind flange devices.

[0077] This invention provides a four-eccentric blind flange quick-change device, which has the advantages of simple operation, good sealing performance, rapid switching, and light weight. It can be widely used in oil and gas valve devices, acetaldehyde recovery devices, atmospheric pressure storage tank devices, maleic anhydride heat exchanger devices, and other working conditions where the weight of the blind flange is strictly controlled. Compared with traditional figure-eight blind flanges, this device eliminates the cumbersome process of disassembling bolts and nuts, and only one person is needed to easily and quickly complete the switching between the open and blind ends. It has obvious advantages in terms of economy, safety, and convenience.

[0078] The contents not described in detail in this specification are existing technologies known to those skilled in the art.

Claims

1. A four-eccentric blind plate rapid switching device, characterized in that... include: The structure comprises: a lower valve body assembly (1), an upper valve body assembly (2), a slide plate assembly (3), a four-eccentric synchronous clamping mechanism (4), a center positioning sliding guide mechanism (5), a drive mechanism (6), and a safety lock mechanism (7); wherein: The lower valve body assembly (1) and the upper valve body assembly (2) have the same shape and structure. The main body is a rectangular plate structure with a through hole in the middle. A flange is provided on one side of the through hole to connect with the flange of the installed pipe, and the other side is a sealing surface. The lower valve body assembly (1) and the upper valve body assembly (2) are installed with their sealing surfaces facing each other. The sliding plate assembly (3) is located between the sealing surfaces of the lower valve body assembly (1) and the upper valve body assembly (2) and can slide. It is divided into two sections: one section has a through hole in the center and the other section does not have a hole in the center, which is used to cut off the medium. The four-eccentric synchronous clamping mechanism (4) is located on both sides of the lower valve body assembly (1) and the upper valve body assembly (2) and is used to clamp the lower valve body assembly (1) and the upper valve body assembly (2); the four-eccentric synchronous clamping mechanism (4) includes: four eccentric shafts, four concentric shafts (403), two crank connecting rods (409), and one crank synchronous connecting rod (410) to ensure the synchronous characteristics of the four-eccentric synchronous clamping mechanism; The central positioning sliding guide mechanism (5) is located around the slide plate assembly (3) to make the working positions of the lower valve body assembly (1), the upper valve body assembly (2) and the middle slide plate assembly (3) coaxially aligned, and at the same time enable the slide plate assembly (3) to slide and be positioned quickly along the predetermined track; The drive mechanism (6) is located on the four-eccentric synchronous clamping mechanism (4) and drives the four-eccentric synchronous clamping mechanism (4) to clamp the lower valve body assembly (1) and the upper valve body assembly (2). The safety lock mechanism (7) is fixed on one side of the four-eccentric synchronous clamping mechanism. When the lower valve body assembly (1) and the upper valve body assembly (2) are clamped, the safety lock mechanism (7) can prevent the drive mechanism (6) from operating, thus preventing misoperation.

2. The four-eccentric blind plate quick switching device according to claim 1, characterized in that: The lower valve body assembly (1) includes a lower valve body (101) and a lower pressure block (102), and the upper valve body assembly (2) includes an upper valve body (201) and an upper pressure block (202). The through hole of the lower valve body assembly (1) is the same size as the diameter of the tubular structure; The lower valve body (101) has four lower pressure blocks (102) with through holes at the four corners of the rectangular plate structure, and the upper valve body (201) has four upper pressure blocks (202) with through holes at the four corners of the middle rectangular plate structure. The axial direction of the through holes is perpendicular to the sliding direction of the slide plate assembly (3).

3. The four-eccentric blind plate quick switching device according to claim 1, characterized in that: The skateboard assembly (3) includes a blind plate (301), a perforated plate (302), and a sealing ring (303), specifically: The slide plate assembly (3) has half of the through hole as an orifice plate (302) and the other half as a blind plate (301) for cutting off the medium. The through hole size is the same as that of the lower valve body assembly (1) and the upper valve body assembly (2). The blind flange (301) is provided with a sealing ring groove with the same size as the through hole on the upper valve body assembly and the lower valve body assembly, and a sealing ring is installed in the sealing ring groove; The blind plate (301) and the orifice plate (302) are connected together by a mounting pin. After the pin is removed, the blind plate (301) and the orifice plate (302) can be used separately.

4. The four-eccentric blind plate quick switching device according to claim 1, characterized in that: The four-eccentric synchronous clamping mechanism (4) also includes: four shaft connecting rods (404). These structures ensure the clamping characteristics of the four-eccentric synchronous clamping mechanism, wherein: Each eccentric shaft passes through a through hole of a lower pressure block (102). Each eccentric shaft is divided into four sections, each with a different shaft diameter, numbered from thickest to thinnest as the first section, second section, third section, and fourth section. The first section of the eccentric shaft mates with the lower pressure block (102). The thickest section has a groove at its end for installing a retaining ring. The second section of the eccentric shaft has a pin hole. Four concentric shafts (403) pass through the through holes of the four upper pressure blocks respectively. The concentric shafts (403) are divided into two sections. The thicker section of the concentric shaft (403) cooperates with the upper pressure block (202). Grooves are provided at the ends of both the thicker and thinner sections for installing retaining rings. The shaft connecting rod (404) is in the shape of a channel steel, with a through hole at each end. The diameter of one through hole is the same as the diameter of the second section of the eccentric shaft, and the size of the other through hole is the same as the thinner section of the concentric shaft. Each shaft connecting rod (404) connects a set of corresponding eccentric shafts and concentric shafts. Through the action of the shaft connecting rod (404), the upper pressure block (202), and the retaining rings at the end grooves of the thicker and thinner sections of the concentric shaft (403), the relative position of the concentric shaft (403) and the upper valve body assembly (2) is kept fixed. The lower valve body assembly (1) and the upper valve body assembly (2) are connected by the eccentric shaft, the concentric shaft (403), and the shaft connecting rod (404) in the four-eccentric synchronous clamping mechanism (4). At the same time, through the action of the pin and the retaining ring installed at the end of the thickest section of the shaft, the relative position of the first eccentric shaft (401), the second eccentric shaft (402), and the lower valve body assembly (1) is kept fixed.

5. A four-eccentric blind plate quick switching device according to claim 4, characterized in that: The four-eccentric synchronous clamping mechanism (4) further includes: a first crank (405), a second crank (406), two third cranks (407), and a crankshaft (408) welded to the cranks; wherein: On one side parallel to the sliding direction of the skateboard assembly (3), a first crank (405) is connected to a shaft link (404), one end of which is connected to one end of a crank link (409) via a crank shaft (408), and the other end of the crank link (409) is connected to a third crank (407) via a crank shaft (408). The third crank (407) is connected to another shaft link (404) on the same side. The first crank (405) is provided with a through hole for welding the crankshaft (408), a through hole with keyways at both ends, a square hole, and a conventional through hole, the conventional through hole cooperating with the second section of the corresponding eccentric shaft; one end of the drive mechanism (6) is located in the square hole; the third crank (407) is provided with a through hole for welding the crankshaft (408), a conventional through hole, the conventional through hole cooperating with the second section of the corresponding eccentric shaft; Similarly, on the other side parallel to the sliding direction of the skateboard assembly (3), the second crank (406) is connected to a shaft connecting rod (404), one end of which is connected to one end of the crank connecting rod (409) through the crank shaft (408), and the other end of the crank connecting rod is connected to the third crank (407) through the crank shaft (408). The third crank (407) is connected to another shaft connecting rod (404) on the same side. The second crank (406) is provided with a through hole for welding the crankshaft (408), a through hole with keyways at both ends, and a conventional through hole that mates with the second section of the corresponding eccentric shaft. The third crank (407) on this side is also provided with a through hole for welding the crankshaft (408), a conventional through hole that mates with the second section of the corresponding eccentric shaft. The crank synchronizing connecting rod (410) has four keyways at both ends and threaded holes on both end faces. The crank synchronizing connecting rod (410) passes through the keyway through holes of the first crank (405) and the second crank (406), and is connected to the first crank (405) and the second crank (406) by a flat key. The two ends are fixed by screws to fasten the shaft end retaining rings.

6. A four-eccentric blind plate rapid switching device according to claim 2, characterized in that: The center positioning sliding guide mechanism (5) includes a limiting plate (501), a flanged bushing (502), a valve body guide post (503), and a handle (504), specifically: The limiting plate (501) is fastened to both ends of the slide plate assembly (3) by bolts. When the slide plate assembly (3) slides to the position where the blind plate (301) or the perforated plate (302) is concentric with the through hole of the lower valve body (101) and the upper valve body (201), the limiting plate (501) is attached to the side of the upper valve body (201) to limit the extreme sliding of the slide plate assembly (3). The flanged bushing (502) is installed on the lower valve body (101) and the upper valve body (201) parallel to both sides of the slide plate assembly (3) to form two slide rails, and the sliding direction of the slide plate assembly (3) is restricted by the flange; One end of the valve body guide post (503) is a smooth shaft, and the other end is threaded. It is located between the lower valve body (101) and the upper valve body (201), parallel to the axial direction of the through hole of the lower valve body (101) and the upper valve body (201), restricting the lower valve body (101) and the upper valve body (201) to move only along the axial direction of their upper through hole; A handle (504) is mounted on a limit plate (501) for pushing or pulling the skateboard assembly (3).

7. A four-eccentric blind plate quick-switching device according to claim 5, characterized in that: The drive mechanism (6) is a square rod-shaped wrench (601) with a bent end to fit into the square hole of the first crank (405). By rotating the wrench, the first crank (405) is rotated, and then the four eccentric shafts rotate synchronously through the combined action of the crank connecting rod (409) and the crank synchronous connecting rod (410). On both sides parallel to the sliding direction of the slide plate assembly (3), the eccentric shaft corresponding to one side of the wrench (601) is designated as the first eccentric shaft (401), and the eccentric shaft on the opposite side is designated as the second eccentric shaft (402). The difference between the first eccentric shaft (401) and the second eccentric shaft (402) lies only in the angle between the center line of the pin hole used to connect the crank and the line connecting the centers of each segment of the eccentric shaft. If the angle between the center line of the pin hole of the first eccentric shaft (401) and the line connecting the center of each segment of the shaft is α, then the angle between the center line of the pin hole of the second eccentric shaft (402) and the line connecting the center of each segment of the eccentric shaft is -α, ensuring that when the wrench (601) rotates on one side, the direction and distance of displacement generated by the rotation of the first eccentric shaft (401) and the second eccentric shaft (402) on both sides are the same. The direction and distance of displacement transmitted to the concentric shaft (403) through the four shaft connecting rods (404) are also the same, thereby driving the lower valve body (101) and the upper valve body (201) to move closer or further away from each other, realizing the loosening and clamping of the slide assembly (3).

8. A four-eccentric blind plate quick switching device according to claim 7, characterized in that: The safety lock mechanism (7) consists of a buckle plate (701) and a snap ring (702), and is located on the crank connecting rod (409) near the third crank (407); The locking plate (701) is provided with a notch, a through hole and a threaded hole; a hexagonal head shoulder screw is used to pass through the through hole and mate with the threaded hole on the crank connecting rod (409); a knurled head screw is installed at the threaded hole of the locking plate (701); a flexible cylindrical pin is provided in the blind hole on the crank connecting rod (409) near the locking plate (701); the two rings of the snap ring (702) are respectively fitted at the hexagonal head shoulder screw and the flexible cylindrical pin on the crank connecting rod, and the other end abuts against the knurled head screw; When the four-eccentric synchronous clamping mechanism (4) clamps the slide assembly (3), the notch of the locking plate (701) can lock the fourth segment of the eccentric shaft away from the wrench, thereby restricting the movement of the wrench (601); when releasing the slide assembly (3), the snap ring (702) must be activated first so that the notch of the locking plate (701) no longer locks the thinnest segment of the eccentric shaft before the wrench (601) can be operated.

Images