A wedge-type double-layer axial sealing sleeve

Abstract

The present invention discloses a wedge-type double-layer axial sealing sleeve, which is a micro-leakage sealing device at the connection between a valve stem and a packing gland of a conveying pipeline valve. The double-layer axial sealing sleeve is arranged on the packing gland and the valve stem to increase the micro-leakage sealing treatment at the packing gland and the valve stem. The double-layer axial sealing sleeve is divided into a first inner sleeve and a first outer sleeve. The first inner sleeve matched with the valve stem is arranged above the packing gland. The first outer sleeve is screwed on the first inner sleeve to form an integral wedge-type double-layer axial sealing sleeve. The wedge-type double-layer axial sealing sleeve is rotated and pressed against the packing gland, so that the rubber gasket or soft sealing material therebetween is compressed and deformed, and filled in the gap between the valve stem and the packing gland, thereby achieving the sealing effect.

Description

Technical Field

[0001] The invention relates to the technical field of micro-leakage treatment of axial seals, in particular to the field of micro-leakage treatment of axial seals of valve stems. Background Art

[0002] In response to the national blue sky plan, experts from all walks of life have tackled the micro-leakage of volatile organic compounds (VOCs) and toxic and hazardous volatile organic compounds (OHAPs) in axial sealing technology. Because the places where axial seals are used in large quantities cannot stop immediately for treatment due to restrictive reasons such as long working cycles and extremely high shutdown costs, they can only be repaired. For example, petrochemical enterprises use at least a quarterly working cycle. There are different ways to deal with leaks at home and abroad. However, due to the particularity and complexity of their structures, the treatment costs are high.

[0003] During long-term use, the opening and closing of the valve is driven by the valve stem. The sealing between the valve body and the valve stem of the traditional valve is achieved by compressing the packing with the packing gland. However, after long-term use, micro-leakage will occur, especially the sealing at the valve stem is greatly affected. Summary of the invention

[0004] In view of the above problems, the present invention provides a wedge-type double-layer axial sealing sleeve.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: for the two situations of the valve stem being a bare rod and a screw rod, a wedge-type double-layer axial sealing sleeve is also divided into two technical solutions. The first is that the entire valve stem is a screw rod: the double-layer axial sealing sleeve is divided into a first inner sleeve and a first outer sleeve, the first inner sleeve is spliced ​​into an annular sleeve body by two first wedges, the first inner sleeve has an inverted "T"-shaped cylindrical shape, the lower half of the first inner sleeve is provided with a trumpet-shaped oblique groove, one side of the first wedge is provided with a square groove, and the other side is provided with a square protrusion matching the square groove, the inner ring of the first inner sleeve A first thread is machined, a second thread is machined on the outer ring of the first inner sleeve, the first inner sleeve is screwed with the first outer sleeve through the second thread, the first outer sleeve is spliced ​​into an annular sleeve body by two second wedge blocks, a third thread is machined on the inner ring of the first outer sleeve to match the second thread, one side of the second wedge block is provided with a "T"-shaped groove, and the other side is provided with a "T"-shaped protrusion to match the "T"-shaped groove. After the two second wedge blocks are cross-staggered and put on the valve stem, they are horizontally clamped through the "T"-shaped groove and the protrusion, and after being spliced ​​into the annular sleeve body of the first outer sleeve, they are put on and screwed on the first inner sleeve.

[0006] Furthermore, the first thread is a trapezoidal thread matching the valve stem.

[0007] Furthermore, a wrench position is provided on the outer ring of the first outer sleeve.

[0008] Furthermore, a bell-mouth shaped oblique groove is provided on the inner side of the lower half of the first inner sleeve.

[0009] Furthermore, a rubber ring is sleeved inside the bell-mouth shaped oblique groove, the first inner sleeve bell-mouth shaped oblique groove is pressed on the rubber ring, the bottom surface of the rubber ring is pressed on the top surface of the packing gland, and the rubber ring is deformed under the pressure between the bell-mouth shaped oblique groove and the packing gland, filling the gap between the packing gland and the valve stem (1).

[0010] The second type is a bare rod with a certain length in the lower half of the valve stem: a second inner sleeve and a second outer sleeve are added, the second inner sleeve is cylindrical, the outer wall of the second inner sleeve is processed with a second thread identical to the first inner sleeve, the inner wall of the second outer sleeve is processed with a third thread identical to the first outer sleeve, the second outer sleeve is screwed to the upper half of the second inner sleeve through the third thread, the second inner sleeve and the second outer sleeve are processed with corresponding bolt holes, and are fixed to the valve stem through bolts, and the upper half of the first outer sleeve is screwed to the lower half of the second inner sleeve through the third thread.

[0011] The outer ring of the second outer sleeve is provided with the same wrench position as that of the first outer sleeve.

[0012] Principle: The first type is when the valve stems are all screw rods: after the two first wedge blocks are put on the valve stem, they are buckled one by one through the square protrusions and square grooves to form a first inner sleeve as a whole, which is screwed to the valve stem through the first thread. After the first inner sleeve is screwed, it limits the up and down displacement and the displacement in the axial direction after matching with the valve stem, and can only be separated on both sides; after the two second wedge blocks are cross-staggered and put on the valve stem, they are horizontally clamped through the "T"-shaped grooves and protrusions to form a first outer sleeve as a whole, and the second thread of the first wedge block is tightened with the third thread of the second wedge block to form a wedge-type double-layer axial sealing sleeve as a whole, and the wedge-type double-layer axial sealing sleeve as a whole is tightened along the trapezoidal thread of the valve stem. The first outer sleeve is tightened by the thread. After tightening, the first outer sleeve limits the displacement of the first inner sleeve that can be separated to both sides, so that the first inner sleeve is completely and stably tightened inside the valve stem and the first outer sleeve without displacement. Furthermore, the "T"-shaped groove and the protrusion of the first outer sleeve itself limit the displacement of the first outer sleeve up and down and on both sides. While being tightened with the first inner sleeve, the first outer sleeve also limits the horizontal axial displacement, so that the first inner sleeve and the first outer sleeve are stably tightened on the valve stem. The inside of the bell-mouth-shaped oblique groove of the first inner sleeve is filled with a rubber ring. Under the tightening pressure, the rubber ring fills the inside of the bell-mouth-shaped oblique groove to eliminate the micro-leakage at the valve stem.

[0013] The second type is when there is a partial bare stem in the lower half of the valve stem, a second inner sleeve and a second outer sleeve are added on the basis of the first outer sleeve and the first inner sleeve, the second outer sleeve is screwed on the upper half of the second inner sleeve, and is fixed to the valve stem by bolts passing through the screw holes of the second outer sleeve and the second inner sleeve, wherein the upper half of the first outer sleeve is screwed on the lower half of the second inner sleeve, and the lower half of the first outer sleeve is screwed on the first inner sleeve. Because the second inner sleeve and the second outer sleeve have been fixed to the valve stem by bolts and screw holes, the first outer sleeve is rotated by the wrench through the wrench to rotate downward, and the lower half of the first inner sleeve is driven to apply pressure downward. After pressure is applied, the rubber ring fills the inside of the bell-shaped oblique groove to eliminate micro-leakage at the valve stem.

[0014] From the above description of the structure of the present invention, it can be seen that compared with the prior art, the present invention has the following advantages:

[0015] Compared with the prior art, the present invention achieves fast, convenient, and effective treatment of micro-leakage at the existing valve stem; the micro-leakage treatment operation is simple, the cost is low, and it meets environmental protection requirements; furthermore, because the valve stem is divided into a full-threaded rod and a partial bare rod, the structure of the present invention also has a targeted solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of this application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 It is a schematic diagram of the installation structure of a wedge-type double-layer axial sealing sleeve of the present invention;

[0018] Figure 2 This is a schematic diagram of the structure of the first inner sleeve of a wedge-type double-layer axial sealing sleeve of the present invention;

[0019] Figure 3 This is a schematic diagram of the first outer shell structure of a wedge-type double-layer axial sealing sleeve of the present invention;

[0020] Figure 4 A schematic diagram of the structure of a block-type double-layer axial sealing sleeve of the present invention when the first outer shell is spliced

[0021] Figure 5 It is a schematic diagram of the rubber ring structure of a wedge-type double-layer axial sealing sleeve of the present invention;

[0022] Figure 6 This is a schematic structural diagram of a second embodiment of a wedge-type double-layer axial sealing sleeve of the present invention;

[0023] Figure 7 This is a schematic diagram of the structure of the second inner sleeve of a wedge-type double-layer axial sealing sleeve of the present invention;

[0024] Figure 8 This is a schematic diagram of the structure of the second outer sleeve of a wedge-type double-layer axial sealing sleeve of the present invention;

[0025] Fig. 9 This is a schematic diagram of the lengthened structure of the first outer sleeve of a wedge-type double-layer axial sealing sleeve suitable for Example 2 of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Example

[0027] The valve stem 1 is threaded, refer to Figures 1 to 5 A double-layer axial sealing sleeve of a wedge block type is a sealing device for the connection between the valve stem 1 and the packing gland 4 of the conveying pipeline valve. The packing 2 is compressed by the packing gland 4 to achieve sealing with the valve stem 1. The double-layer axial sealing sleeve is arranged on the packing gland 4. The double-layer axial sealing sleeve is divided into a first inner sleeve 5 and a first outer sleeve 6. The first inner sleeve 5 is spliced ​​into an annular sleeve body by two first wedge blocks 7. One side of the first wedge block is provided with a square groove 8, and the other side is provided with a square convex block 10 matched with the square groove. The inner ring of the first inner sleeve 5 is machined with a first thread matched with the valve stem thread, and the outer ring of the first inner sleeve 5 is machined with a first thread matched with the valve stem thread. A second thread is processed, and the first inner sleeve 5 is screwed with the first outer sleeve 6 through the second thread. The first outer sleeve 6 is spliced ​​into an annular sleeve body by two second wedges 11. The inner ring of the first outer sleeve 6 is machined with a third thread that cooperates with the second thread of the first inner sleeve 5. One side of the second wedge is provided with a "T"-shaped groove 12, and the other side is provided with a "T"-shaped protrusion 13 that cooperates with the "T"-shaped groove. After the two second wedges 11 are cross-staggered and sleeved on the valve stem, they are transversely clamped through the "T"-shaped groove 12 and the protrusion 13, and after being spliced ​​into the first outer sleeve annular sleeve body, they are sleeved and screwed on the first inner sleeve 5.

[0028] The first thread is a trapezoidal thread matching the valve stem.

[0029] The first inner sleeve 5 has an inverted "T"-shaped cylindrical shape, and a bell-mouth-shaped oblique groove 14 is provided in the lower half of the first inner sleeve.

[0030] A rubber ring 15 is sleeved inside the bell-mouth oblique groove, the first inner bell-mouth oblique groove 14 is pressed on the rubber ring, and the bottom surface of the rubber ring 15 is pressed on the top surface of the packing gland 4. The rubber ring is deformed under the extrusion between the bell-mouth oblique groove 14 and the packing gland 4 to fill the gap between the packing gland 4 and the valve stem 1.

[0031] After the two first wedge blocks 7 are put on the valve stem 1, the square protrusions 10 and the square grooves 8 are interlocked one by one to form a first inner sleeve 5 as a whole, which is screwed to the valve stem through the first thread; after the two second wedge blocks 11 are cross-staggered and put on the valve stem 1, they are transversely clamped through the "T"-shaped grooves 12 and the protrusions 13 to form a first outer sleeve 6 as a whole, and the second thread of the first wedge block 7 and the third thread of the second wedge block 11 are tightened to form a wedge-type double-layer axial sealing sleeve as a whole, and the wedge-type double-layer axial sealing sleeve as a whole is tightened along the trapezoidal thread of the valve stem 1, and the inside of the trumpet-mouth oblique groove 14 of the first inner sleeve is provided with a rubber ring 15 to fill it. Under the tightening pressure, the rubber ring 15 will fill the inside of the trumpet-mouth oblique groove 14 to eliminate the micro-leakage at the valve stem 1. Example

[0032] The lower half of the valve stem 1 is a polished stem. Figures 6 to 9 A second inner sleeve 16 and a second outer sleeve 17 are added above the wedge-type double-layer axial sealing sleeve. The second inner sleeve 16 is cylindrical. The outer wall of the second inner sleeve 16 is processed with a second thread identical to that of the first inner sleeve 5. The inner wall of the second outer sleeve 17 is processed with a third thread identical to that of the first outer sleeve 6. The second outer sleeve 17 is screwed to the upper half of the second inner sleeve 16 through the third thread. The second inner sleeve 16 and the second outer sleeve 17 are processed with corresponding bolt holes 18 and are fixed to the valve stem 1 through bolts. The upper half of the first outer sleeve 6 is screwed to the lower half of the second inner sleeve 16 through the third thread. The first outer sleeve 6 is rotated. Under the action of the thread of the lower half of the second inner sleeve 16, the first outer sleeve 6 drives the first inner sleeve 5 to rotate downward. The inside of the bell-mouth-shaped oblique groove 14 of the first inner sleeve is filled with a rubber ring 15. Under the tightening pressure, the rubber ring 15 fills the inside of the bell-mouth-shaped oblique groove 14 to eliminate the micro-leakage at the valve stem 1.

[0033] Among them, the lower half of the valve stem is a smooth stem, and the inner side wall of the first inner sleeve and the inner side wall of the second inner sleeve are both processed into smooth surfaces to match the valve stem.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A wedge-type double-layer axial sealing sleeve is a sealing device for the connection between a valve stem (1) and a packing gland (4) of a conveying pipeline valve, wherein the packing (2) is fixed and sealed to the valve stem (1) through the packing gland (4), and is characterized in that: The double-layer axial sealing sleeve is divided into a first inner sleeve (5) and a first outer sleeve (6). The first inner sleeve (5) is arranged above the packing gland and matches the valve stem thread. The first inner sleeve is composed of two first wedge blocks (7) spliced ​​into an annular sleeve body. One side of the first wedge blocks is provided with a square groove (8), and the other side is provided with a square protrusion (10) matching the square groove. The inner ring of the first inner sleeve (5) is machined with a first thread matching the valve stem thread, and the outer ring of the first inner sleeve (5) is machined with a second thread. The first inner sleeve (5) is screwed into the valve stem through the second thread. A first outer sleeve (6) is connected, the first outer sleeve is formed by two second wedge blocks (11) spliced ​​together into an annular sleeve body, the inner ring of the first outer sleeve is machined with a third thread that matches the second thread, one side of the second wedge blocks is provided with a "T"-shaped groove (12), and the other side is provided with a "T"-shaped protrusion (13) that matches the "T"-shaped groove. After the two second wedge blocks (11) are cross-staggered and sleeved on the valve stem, they are transversely clamped through the "T"-shaped groove (12) and the protrusion (13), spliced ​​into the first outer sleeve annular sleeve body, and then sleeved and screwed on the first inner sleeve (5).

2. The wedge-type double-layer axial sealing sleeve according to claim 1, characterized in that: The first thread is a trapezoidal thread matching the valve stem.

3. The wedge-type double-layer axial sealing sleeve according to claim 1, characterized in that: The first inner sleeve (5) has an inverted "T"-shaped cylindrical shape, and a bell-mouth-shaped oblique groove (14) is provided on the inner side of the lower half of the first inner sleeve.

4. The wedge-type double-layer axial sealing sleeve according to claim 3, characterized in that: A rubber ring (15) is sleeved inside the bell-mouth shaped oblique groove (14); the bell-mouth shaped oblique groove (14) in the first inner sleeve is pressed on the rubber ring; the bottom surface of the rubber ring (15) is pressed on the top surface of the packing gland (4); the rubber ring is deformed under the pressure between the bell-mouth shaped oblique groove (14) and the packing gland (4), thereby filling the gap between the packing gland (4) and the valve stem (1).

5. The wedge-type double-layer axial sealing sleeve according to claim 1, characterized in that: The outer ring of the first outer sleeve (6) is provided with a wrench position.

6. The wedge-type double-layer axial sealing sleeve according to claim 1, characterized in that: A second inner sleeve (16) and a second outer sleeve (17) are additionally provided. The second inner sleeve (16) is cylindrical. The outer wall of the second inner sleeve (16) is processed with a second thread identical to that of the first inner sleeve (5). The inner wall of the second outer sleeve (17) is processed with a third thread identical to that of the first outer sleeve (6). The second outer sleeve (17) is screwed onto the upper half of the second inner sleeve (16) via the third thread. The second inner sleeve (16) and the second outer sleeve (17) are processed with corresponding bolt holes (18) and are fixed to the valve stem (1) via bolts. The upper half of the first outer sleeve (6) is screwed onto the lower half of the second inner sleeve (16) via the third thread.

7. The wedge-type double-layer axial sealing sleeve according to claim 6, characterized in that: The outer ring of the second outer sleeve (17) is provided with a wrench position which is the same as that of the first outer sleeve.

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