CN112253778A

CN112253778A - Double plate valve

Info

Publication number: CN112253778A
Application number: CN202011061683.3A
Authority: CN
Inventors: 丁英仁; 郭玉生; 韩静波; 苏祥; 郭金; 赵宇琪; 张博文
Original assignee: Beijing Aerospace Petrochemical Technology and Equipment Engineering Corp Ltd
Current assignee: Beijing Aerospace Petrochemical Technology and Equipment Engineering Corp Ltd
Priority date: 2020-09-30
Filing date: 2020-09-30
Publication date: 2021-01-22
Anticipated expiration: 2040-09-30
Also published as: CN112253778B

Abstract

The invention discloses a double-plate valve which comprises a valve body, a valve seat, a valve cover, a valve plate, a pressing block, an upper valve rod, a lower valve rod, a bottom cover, a support assembly, a coupling joint and an actuator, wherein the valve body is respectively connected with the valve cover and the bottom cover, the upper part of the valve cover is connected with the support assembly, the support assembly is connected with the actuator, the valve body is provided with the valve seat, the valve plate and the pressing block are symmetrically arranged in the middle of the valve seat, the upper valve rod and the lower valve rod are connected through the coupling joint, the valve plate is provided with a guide strip, the valve body is provided with a guide rail, the guide strip slides on the guide rail when the valve plate moves, the guide rail is subjected to segmented surfacing welding, and the guide rail is connected together through a head. Even if the welding seam of individual valve body guide rail and valve body ftractures, because the connection structure of head, the guide rail can not drop, rock, can not lead to the valve card to die.

Description

Double plate valve

Technical Field

The invention relates to a valve, in particular to a double-plate valve.

Background

The double-plate valve is widely applied to various devices in petrochemical industry as a cut-off valve for cutting off medium fluid, the valve is normally opened or closed, the switch operation is performed only when needed, and the switching frequency is low.

The low-carbon olefins such as ethylene and propylene are important basic chemical raw materials, and in recent years, with the increasing demand of the development of modern chemical industry for low-carbon olefins and the gradual shortage of petroleum resources, the traditional industrial route for preparing olefins from petroleum can not meet the industrial demand gradually. Along with the development of national economy of China, particularly under the resource condition of more coal and less oil in China, the contradiction between supply and demand is increasingly prominent. Under the background, the preparation of olefin from methanol or the preparation of olefin from propane becomes the most effective way for solving the shortage of petroleum resources in China and promoting the rapid development of the low-carbon olefin industry in China.

The key equipment of the process for preparing olefin from methanol or preparing olefin from propane is an olefin reactor, and raw materials enter the reactor and are converted into olefin products through a complex process. The processes of raw material feeding, product discharging, reduction, scorching and the like of the reactor all need a plurality of double-plate valves to work cooperatively through time sequence action under the control of DCS, so that the whole reaction process is completed. The reaction process is very rapid, the switching frequency of the switch of the double-plate valve is required to be very high, the double-plate valve is operated by a hydraulic actuator at the temperature of over 600 ℃, and the switching time does not exceed 10 s. In addition, the valve bore of the reactor is generally large (maximum NPS48), the installation mode is that the valve rod is horizontal, the weight of the valve internals reaches several tons, and the gravity of the internals becomes an important factor which seriously influences the motion stability of the valve. The valve needs to be operated reliably for a long time, and great economic loss is brought once the device is stopped due to the failure of the valve.

In conclusion, the olefin reactor puts forward severe requirements on the double-plate valve such as high frequency, high temperature, high speed, high reliability, long service life, easy maintenance and the like, and the conventional valve structure and technical indexes can not meet the requirements. Therefore, a double-plate valve which can meet the process requirements is urgently needed.

Disclosure of Invention

The invention aims to provide a double valve which can adapt to the working condition with the harsh requirement.

In the double valve according to the first aspect of the invention, the double valve comprises a valve body, a valve seat, a valve cover, a valve plate, a pressing block, an upper valve rod, a lower valve rod, a bottom cover, a bracket assembly, a coupling and an actuator, wherein the valve body is respectively connected with the valve cover and the bottom cover, the upper part of the valve cover is connected with the bracket component, the support component is connected with the actuator, the valve seat is arranged on the valve body, the valve plate and the pressing block are symmetrically arranged in the middle of the valve seat, the upper valve rod is connected with the lower valve rod through the coupling joint, the valve plate is provided with a guide strip, the valve body is provided with a guide rail, the guide strip slides on the guide rail when the valve plate moves, the guide rail is subjected to segmented surfacing welding, and the guide rails are connected together by a head structure of any one of a T-head, a screw head, a cylinder head and a spade head. According to the first scheme of the invention, the valve can adapt to the condition that the caliber of the valve is more than 30 inches, and the sectional guide rails on the valve body are connected together through different head structures, so that the friction force in the opening and closing process of the valve can be transmitted to all the guide rails, the stress borne by the welding line of a single guide rail is reduced, the manufacturing difficulty of the single guide rail is greatly reduced, the deformation of the guide rail is reduced, and the precision of the guide rail can be better ensured. Moreover, even if the welding seams of the guide rails of the individual valve bodies and the valve bodies are cracked, the guide rails cannot fall off or shake due to the connection structure of the head parts, and the valve cannot be blocked.

In the double valve according to the second aspect of the invention, the head structure of the guide rail is provided with a gap at the position of the connection. According to the second aspect of the present invention, the temperature stress caused by thermal expansion can be reduced.

In the double valve according to the third aspect of the invention, the valve plate includes an upper valve plate and a lower valve plate, and 3 blind holes are provided at the same positions of the upper valve plate and the lower valve plate, each pair of blind holes being provided with a pin in the middle thereof and connected together by the pin. According to the third scheme of the invention, the pins are arranged between the valve plates, so that the synchronism of the movement of the two valve plates during horizontal installation can be improved, and the reliability of sealing is improved.

According to a fourth scheme of the invention, two limiting columns are arranged on the valve cover, one of the limiting columns is provided with a group of disc springs, and the group of disc springs are impacted by the coupling joint and compressed when the double-plate valve is closed. According to the fourth scheme of the invention, the group of disc springs arranged on the valve cover can effectively reduce the impact on the sealing surface when the valve is closed.

In the double valve according to the fifth aspect of the present invention, cylindrical guide posts are provided on both sides of the bracket assembly, the guide posts are connected with the bracket of the bracket assembly by adjusting bolts and screws, and the distance from the guide posts to the center of the bracket assembly is adjusted by adjusting the screwing depth of the adjusting bolts on the bracket. According to the fifth scheme of the invention, the adjustable guide post structure is arranged on the support, so that the valve rod can be accurately guided. The faults of valve movement jamming, valve rod scraping damage and the like caused by factors such as gravity, machining errors and the like are avoided.

In the double valve according to the sixth aspect of the invention, the pressure block is provided with a removable wear plate. According to the sixth scheme of the invention, the replaceable wear-resisting plate is arranged on the pressing block, so that the maintainability of the valve is improved.

In the double valve according to the seventh aspect of the present invention, a spacer is provided between the removable wear plate and the pressure block. According to the seventh aspect of the present invention, by adding the adjustment shim, wear and other dimensional cumulative errors can be compensated for.

In the double valve according to the eighth aspect of the present invention, an anticorrosive liner is welded to the valve seat. According to the eighth aspect of the invention, the corrosion resistance of the valve is improved by adding the corrosion-resistant liner pipe to the flow channel.

Drawings

Features, advantages and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, wherein like reference numerals denote like elements, and in which:

FIG. 1 is a schematic view of the valve structure of the present invention;

FIG. 2 is a stainless steel build-up welding valve plate wear-resistant guide strip;

FIG. 3 is a schematic view of an integral valve plate wear guide strip;

FIG. 4 is a schematic view of the valve approaching closure, the disc spring set beginning to compress, and the coupling beginning to cushion;

FIG. 5 is a schematic view of the position of the coupling with the position-limiting bolt when the valve is fully closed;

FIG. 6 is a schematic view of a guide rail and valve body;

FIG. 7 is a schematic view of a T-head guide;

FIG. 8 is a schematic view of a flat head guide;

FIG. 9 is a schematic view of a cylinder head guide rail;

FIG. 10 is a schematic view of a screw head guide;

fig. 11a is a schematic view of a first embodiment of a guideway consist;

fig. 11b is a schematic view of a second embodiment of a guideway consist;

FIG. 12 is a schematic view of an adjustable guide post;

FIG. 13 is a schematic view of a valve plate synchronizing pin structure;

FIG. 14 is a schematic view of a compact with replaceable wear plates;

FIG. 15 is a schematic view of a corrosion-resistant steel pipe lining a flow channel.

Detailed Description

Hereinafter, a dual plate valve of an embodiment of the present invention will be described using fig. 1 to 15. Note that the present invention is not limited to the embodiments to be described below.

Referring to fig. 1, there is shown a schematic diagram of the inventive structure of the present invention. As shown in fig. 1, the valve 1 includes a valve body 11, a valve seat 12, a valve cover 13, a valve plate 14, a pressure block 15, an upper stem 161, a lower stem 162, a bottom cover 17, a bracket assembly 18, a coupling 19, an actuator 20, and a post head 21.

The valve body 11 is connected with the valve cover 13 and the bottom cover 17 through flanges, the bracket component 18 is connected with a small flange at the upper part of the valve cover 13, and the actuator 20 is connected with the bracket component 18 through a flange.

Referring to the partial view of fig. 1, the valve body 11 is provided with a recess for a valve seat 12, which is angled with respect to the centre line of the valve 1, and in which recess the valve seat 12 is welded. The valve plate 14 and the pressing block 15 are symmetrically arranged between the two valve seats 12, and the center ball 22 is arranged in the middle of the pressing block 15.

The lower stem 162 is connected to the stud 21, and the stud 21 is inserted into the pressing block 15. The valve plate 14 and the pressing block 15 are provided with inclined planes with the same angle. The pressure piece 15 presses the valve plate 14 against the valve seat 12 when the valve 1 is closed, and drives the valve plate 14 to move together when the valve 1 is opened.

The upper stem 161 and the lower stem 162 are connected by a coupling 19. The actuator 20 moves to drive the upper valve rod 161 to move, thereby realizing the opening and closing of the valve 1.

Next, the valve 1 will be described in more detail.

Valve plate 14 is provided with guide bar 30, and valve body 11 is provided with guide rail 80. As valve plate 14 moves, guide bar 30 slides on guide rails 80. The guide strip 30 is a detachable structure and can be in the following way:

1) in the first embodiment of the guide bar, as shown in fig. 2, the base material 31 of the guide bar 30 is stainless steel, a layer of wear-resistant hard alloy 32 is deposited on the stainless steel, and the stainless steel is fixed on the valve plate 14 through a screw 33, and the screw 33 is in spot welding with the valve plate 14 to prevent looseness;

2) in a second embodiment of the guide bar, as shown in fig. 3, the guide bar 30 is made of an abrasion resistant material 34 such as ceramics other than steel or integrally sintered cemented carbide, and is fixed to the valve plate 14 by a socket head cap screw 35, and the screw 35 is spot-welded to the valve plate 14 to prevent loosening.

To ensure the movement of the valve plate 14, the length L1 of the guide bars is generally set at about 1/3 of the nominal diameter of the valve 1, i.e., the length L1 of the guide bars of the 48-inch valve 1 is about 400mm, the length L1 of the guide bars of 42-inch is about 350mm, and the length L1 of the guide bars of 36-inch is about 300 mm.

As shown in fig. 4, two position-limiting columns 36 are arranged on the valve cover 13, and one of the position-limiting columns 36 is provided with a group of disc springs 37. As shown in fig. 4, when the valve 1 is closed, the coupling 19 first hits the set of disc springs and then contacts the position-limiting post 36. As shown in fig. 5, the compression amount of the set of disc springs 37 is H, so as to buffer the movement of the valve rod during the compression process of the set of disc springs, thus avoiding the rigid collision of the valve plate 14 with the valve seat 12 and protecting the actuator 20.

As shown in fig. 6, 4 sets of guide rails 80 are provided on both sides of the valve body 11, inserted into the guide grooves, and welded with the valve body 11. When the caliber of valve 1 is greater than 30 inches, each set of guide rails 80 is connected together by a plurality of shorter guide rails in a special manner to support the weight of valve plate 14 as valve plate 14 moves. When the caliber of the valve 1 is not more than 30 inches, the guide rail is an integrated guide rail. In the case where each set of guide rails is formed by a plurality of shorter guide rails, the connection between the guide rails may be any one of the following:

as shown in fig. 7, a T-head connection;

as shown in fig. 8, a threaded head connection;

as shown in fig. 9, the cylinder head is connected;

as shown in fig. 10, the tabs are connected.

The guide rails 80 are connected together by the various types of head structures to form a guide rail group, and a gap delta is reserved at the position where the head of the guide rail is connected, so that the temperature stress caused by thermal expansion is reduced, and the delta is generally not less than 1 mm. The grooving position of the T-shaped groove can be on the guide rail hardened surface B, as shown in FIG. 11 a; the slotted position may also be on the side of the rail as shown in fig. 11 b.

The friction force generated by the valve plate 14 and the guide rails during the movement process is borne by the weld seams of the guide rails, in order to reduce the tensile stress borne by the weld seams, the guide strips of the valve plate 14 should fall on the two guide rails at least at the same time, and the length L1 of the guide strips of the valve plate 14 and the length L2 of the segmented guide rails satisfy the following relationship: l2< L1<2L2, so the length L2 of the 48-inch sectional guide rail is 200-400 mm; the length L2 of the 42-inch sectional guide rail is 175-350 mm, and the length L2 of the 36-inch sectional guide rail is 150-300 mm.

As shown in fig. 12, cylindrical guide posts 40 are provided on both sides of the bracket assembly 18, and the guide posts 40 are connected to a bracket 181 of the bracket assembly 18 by adjusting bolts 41 and screws 42. By adjusting the screwing depth of the adjusting bolt 41 on the bracket 181, the distance L from the guide post 40 to the center of the bracket assembly 18 can be adjusted, thereby realizing reliable guide of the valve rod and preventing the valve rod from scraping and jamming.

As shown in fig. 13, the two valve plates 14, i.e., the upper valve plate 14A and the lower valve plate 14B, are provided at the same position with 3 blind holes 50, each pair of blind holes 50 being provided with one pin 51 therebetween, connected together by the pin 51.

As shown in fig. 14, the press block 15 is provided with a replaceable wear plate 60, the wear plate 60 and the press block 15 are fastened together by a screw 61, and an adjustment washer 62 is provided between the wear plate 60 and the press block 15. By adding the adjustment shim 62, wear and other dimensional tolerance stack-up can be compensated for.

As shown in FIG. 15, the flow passage is welded with corrosion resistant structure, which may be a corrosion resistant liner 70, such as TP310, and the corrosion resistant liner 70 is welded with the valve seat 12.

Those skilled in the art will appreciate that those matters not described in detail in the present specification are well known in the art. Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, but various modifications may be made based on the technical spirit of the present invention. For example, the configuration of each device mentioned in the above embodiments is merely an example, and different configurations may be used as necessary.

Claims

1. A double-plate valve is characterized in that: comprises a valve body (11), a valve seat (12), a valve cover (13), a valve plate (14), a pressing block (15), an upper valve rod (161), a lower valve rod (162), a bottom cover (17), a bracket component (18), a coupling joint (19) and an actuator (20), wherein the valve body (11) is respectively connected with the valve cover (13) and the bottom cover (17), the upper part of the valve cover (13) is connected with the bracket component (18), the bracket component (18) is connected with the actuator (20), the valve seat (12) is arranged on the valve body (11), the valve plate (14) and the pressing block (15) are symmetrically arranged in the middle of the valve seat (12), the upper valve rod (161) is connected with the lower valve rod (162) through the coupling joint (19), a guide strip (30) is arranged on the valve plate (14), and a guide rail (80) is arranged on the valve body (11), and when the valve plate (12) moves, the guide bars (30) slide on the guide rails (80), the guide rails (80) are built up in sections, and the guide rails (80) are connected together through a head structure in any one of a T-head type, a screw head type, a cylindrical head type and a flat head type.

2. The double-plate valve according to claim 1, characterized in that: the head structure of the guide rail (80) is reserved with a gap delta at the position of connection.

3. The double-plate valve according to claim 1, characterized in that: the valve plate (14) includes an upper valve plate (14A) and a lower valve plate (14B), and 3 blind holes (50) are provided at the same position of the upper valve plate (14A) and the lower valve plate (14B), each pair of blind holes (50) being provided with a pin (51) therebetween and connected together by the pin (51).

4. The double-plate valve according to claim 1, characterized in that: two limiting columns (36) are arranged on the valve cover (13), one limiting column (36) is provided with a group of disc springs (37), and the group of disc springs (37) are impacted by the coupling joint (19) to be compressed when the double-plate valve is closed.

5. The double-plate valve according to claim 1, characterized in that: the two sides of the bracket component (18) are provided with cylindrical guide columns (40), the guide columns (40) are connected with a bracket (181) of the bracket component (18) through adjusting bolts (41) and screws (42), and the distance from the guide columns (40) to the center of the bracket component (18) is adjusted by adjusting the screwing depth of the adjusting bolts (41) on the bracket (181).

6. The double-plate valve according to claim 1, characterized in that: the pressing block (15) is provided with a detachable wear-resisting plate (60).

7. The double-plate valve according to claim 6, characterized in that: an adjusting gasket (62) is arranged between the detachable wear-resisting plate (60) and the pressing block (15).

8. The double-plate valve according to claim 1, characterized in that: an anti-corrosion liner tube (70) is welded on the valve seat (12).