Scouring-resistant manual blow-down valve

Abstract

The utility model discloses a scouring-resistant manual blow-down valve, and relates to the field of blow-down valves. A traditional angle type blow-down valve has the problems of serious cavitation abrasion, poor sealing performance, high maintenance cost and the like under the working conditions of high temperature and high pressure. The valve comprises a valve body, a valve cover, a valve rod, a valve seat, a sleeve and a hand wheel driving assembly, an inlet flow channel and a vertical inner cavity of the valve body form a Y-shaped straight-through structure, an outlet flow channel, a double-taper sealing structure and a stepped groove valve element are matched, and the inclined downward outlet flow channel and the inlet flow channel form an included angle of 15-25 degrees. And a metal wound gasket seal and a forged steel material. Turbulence is reduced by optimizing the angle of a flow channel, cavitation is restrained through the double conical surfaces and the grooves, the sealing stability is enhanced through the integrated structure, the self-cleaning function is achieved, erosive wear of the valve body can be reduced, the cavitation risk is reduced, the sealing reliability is improved, meanwhile, the maintenance process is simplified, the defects in the prior art are effectively overcome, and the valve is suitable for the harsh industrial environment.

Description

Technical Field

[0001] This utility model relates to the field of drain valves, and in particular to a erosion-resistant manual drain valve. Background Technology

[0002] In industrial fields such as wastewater treatment and petrochemicals, drain valves are key devices for controlling fluid discharge, and their erosion resistance and service life directly affect the stability of the system. In existing technologies, traditional angle drain valves use a 45° Y-shaped valve body structure to reduce the impact of fluid on the sealing surface. However, under high temperature and high pressure conditions, they still have technical defects: when fluid flows through the valve, sudden changes in flow resistance cause a sharp drop in pressure. When the local pressure is lower than the saturated vapor pressure of the medium, bubble rupture can cause cavitation, exacerbating the wear of the valve body and valve core. The flow channel angle and constant diameter cross-section design of traditional Y-type valves cannot completely avoid fluid turbulence and impact, especially when the medium contains particles or corrosive components, easily causing erosion and wear on the valve seat and valve core sealing surfaces. Furthermore, the split valve core and valve stem structure may lead to sealing failure due to assembly gaps, and the entire component needs to be replaced after wear, resulting in high maintenance costs. Utility Model Content

[0003] The technical problem to be solved and the technical task proposed by this utility model is to improve and refine the existing technical solutions, and to provide a erosion-resistant manual drain valve to reduce erosion wear and improve sealing performance. To this end, this utility model adopts the following technical solution.

[0004] A erosion-resistant manual drain valve includes a valve body, a valve cover, a valve stem, a valve seat, a sleeve, and a handwheel drive assembly. The valve seat is located in the lower part of the inner cavity of the valve body. The sleeve is located on top of the valve seat inside the valve body. The valve cover is located on top of the valve body. The handwheel drive assembly is connected to the top of the valve cover via a support column. The handwheel drive assembly is located at the upper end of the valve stem. The valve stem passes through the packing seal assembly at the upper end of the valve cover, the central hole of the valve cover, and then extends into the sleeve from top to bottom. A valve core is provided at the lower end of the valve stem. The guide section of the valve core slides in fit with the inner wall of the sleeve. The lower part of the valve core is a sealing plug. When the sealing plug moves to the bottom, it closes the central flow channel hole of the valve seat. One side of the valve body is provided with... The valve body has a downward-sloping inlet flow channel hole that connects to the vertical valve body cavity above the valve seat. On the other side of the valve body, there is a downward-sloping outlet flow channel hole. The upper end of the outlet flow channel hole connects to the vertical valve body cavity below the valve seat. The centerline of the outlet flow channel hole is offset downwards by 15-25 degrees compared to the centerline of the inlet flow channel hole. The valve seat's central flow channel hole and the sealing plug form a double-tapered sealing structure with a larger upper section and a smaller lower section. The sealing plug includes a first-stage tapered outer cylindrical surface at the top and a second-stage tapered outer cylindrical surface below the first-stage tapered outer cylindrical surface, forming a second-stage taper of the sealing plug. This taper matches the second-stage taper of the valve seat's central flow channel hole, forming a double-tapered sealing structure. The inlet flow channel and the vertical valve body cavity form a Y-shaped straight-through structure, which, together with the downward-sloping outlet flow channel, utilizes the fluid's own gravity and scouring effect to reduce impurity deposition and achieve a "self-cleaning" function. In addition, this structure can reduce turbulence and energy loss, reduce the impact on the valve body wall, has good scouring resistance, and extends service life. Compared with single-cone or flat seals, the double-cone sealing structure increases the sealing contact area, improves the sealing performance under high pressure conditions, and the conical design facilitates automatic centering and reduces wear.

[0005] As a preferred technical approach, the diameter of the outlet flow channel hole is equal to the diameter of the inlet flow channel hole and smaller than the diameter of the valve body cavity below the valve seat. This technical solution, by varying the flow channel diameter, allows the fluid to flow out more rapidly after the pressure inside the valve seat cavity has decreased and stabilized, thus avoiding the formation of local high-pressure zones and reducing the risk of cavitation.

[0006] As a preferred technical approach, the valve stem and valve core are integrated into a single structure. This integrated structure reduces the number of parts, simplifies the structure, reduces maintenance complexity, eliminates assembly gaps caused by separate connections, avoids loosening due to vibration or impact, and improves sealing stability.

[0007] As a preferred technical approach, the second-stage conical outer surface of the sealing plug is provided with 5-7 arc-shaped grooves, which are arranged axially at equal intervals. The grooves form multi-stage throttling, allowing the fluid pressure to be released step by step, ensuring that the pressure at the constriction section is always higher than the saturation pressure, thus suppressing the formation of cavitation bubbles in principle; the arc-shaped grooves can store a small amount of medium during sealing, forming an auxiliary sealing band and improving the sealing reliability under high pressure.

[0008] As a preferred technical means, a metal spiral wound gasket is provided between the valve seat and the valve body, and a metal spiral wound gasket is provided between the valve body and the valve cover. The metal spiral wound gasket is resistant to high temperature and high pressure, and has higher elasticity and anti-aging properties than ordinary gaskets, ensuring that the valve has no external leakage, and is especially suitable for high temperature conditions.

[0009] As a preferred technical approach, the valve body and valve cover are made of integral forged steel. Compared to cast valve bodies, forged steel has a denser structure, stronger pressure resistance and erosion resistance, and is suitable for high-temperature and high-pressure operating conditions.

[0010] As a preferred technical means: the handwheel drive assembly includes a handwheel, a lead screw seat, and a connecting flange. Four support columns are fixedly connected to the connecting flange. The lower middle part of the lead screw seat is rotatably connected to the center hole of the connecting flange via upper and lower secondary bearings. The upper end of the lead screw seat is connected to the handwheel via a key. The upper end of the valve stem has a lead screw section that mates with the lead screw seat. This achieves rigid coupling between the handwheel and the valve stem, ensuring accurate torque transmission. When the handwheel is rotated, the driving force is directly transmitted to the lead screw seat via the key, causing the lead screw seat to rotate, and the lead screw seat drives the valve stem to move vertically.

[0011] Beneficial effects: The inlet flow channel and the vertical valve body cavity form a Y-shaped straight-through structure, which, together with the downward-sloping outlet flow channel, utilizes the fluid's own gravity and scouring effect to reduce impurity deposition and achieve a "self-cleaning" function. In addition, this structure can reduce turbulence and energy loss, reduce the impact on the valve body wall, has good scouring resistance, and extends service life. Compared with single-cone or flat seals, the double-cone sealing structure increases the sealing contact area, improves the sealing performance under high-pressure conditions, and the conical design facilitates automatic centering and reduces wear. The change in flow channel diameter allows the fluid to flow out faster after the pressure in the valve seat cavity is reduced and stabilized, avoiding the generation of local high-pressure areas and reducing the risk of cavitation. The sealing plug structure allows the fluid pressure to be released step by step, ensuring that the pressure at the constriction section is always higher than the saturation pressure, which in principle inhibits the generation of cavitation bubbles. The arc-shaped groove of the sealing plug can store a small amount of medium during sealing, forming an auxiliary sealing band and improving the sealing reliability under high pressure. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of this utility model.

[0013] Figure 2 This is a utility model Figure 1 Enlarged schematic diagram of part A in the middle.

[0014] In the diagram: 1. Valve body; 2. Valve cover; 3. Valve stem; 4. Valve seat; 5. Sleeve; 6. Support column; 7. Limiting anti-rotation block; 8. Valve core; 9. Sealing plug; 10. Metal spiral wound gasket; 11. Packing gasket; 12. Combined packing; 13. Packing sleeve; 14. Packing pressure plate; 15. Handwheel; 16. Screw seat; 17. Connecting flange; 18. Key; 19. Bearing; 101. Inlet flow channel hole; 102. Outlet flow channel hole; 901. Groove. Detailed Implementation

[0015] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings.

[0016] Example 1

[0017] like Figure 1 , 2As shown, a erosion-resistant manual drain valve includes a valve body 1, a valve cover 2, a valve stem 3, a valve seat 4, a sleeve 5, and a handwheel drive assembly. The valve seat 4 is located in the lower part of the inner cavity of the valve body 1. The sleeve 5 is located on the valve seat 4 inside the valve body 1 and mates with the inner cavity of the upper part of the valve body 1. The valve cover 2 is located on the valve body 1, and the middle part of the valve cover 2 extends downward into the inner cavity of the valve body 1 and presses against the sleeve 5. The valve cover 2 and the valve body 1 are connected and fixed by eight sets of fully threaded studs and nuts. The handwheel drive assembly is connected to the upper part of the valve cover 2 by support columns 6. There are four support columns 6, evenly distributed around the valve stem 3. The lower ends of the four support columns 6 are connected and fixed to the upper end of the valve cover 2 by threads. The upper end of each support column 6 is connected and fixed to the handwheel drive assembly by an internal hex bolt. The handwheel drive assembly is connected to the upper end of the valve stem 3 to control the raising and lowering of the valve stem 3. The valve body 3 is equipped with a limit anti-rotation block 7. The valve stem 3 passes through the packing seal assembly at the upper end of the valve cover 2 and the center hole of the valve cover 2 from top to bottom and then extends into the sleeve 5. The lower end of the valve stem 3 is equipped with a valve core 8. The guide section of the valve core 8 slides with the inner wall of the sleeve 5. The lower part of the valve core 8 is a sealing plug 9. When the sealing plug 9 moves down to the bottom, it closes the center flow channel hole of the valve seat 4. The right side of the valve body 1 is equipped with an inlet flow channel hole 101. The inlet flow channel hole 101 is obliquely set and its lower end is connected to the vertical inner cavity of the valve body 1 above the valve seat 4. The left side of the valve body 1 is equipped with an obliquely downward outlet flow channel hole 102. The upper end of the outlet flow channel hole 102 is connected to the vertical inner cavity of the valve body 1 below the valve seat 4, and the upper end of the outlet flow channel is located at the upper end of the conical bottom at the lower end of the inner cavity of the valve body 1. The center line of the outlet flow channel hole 102 is 15 degrees downward than the center line of the inlet flow channel hole 101. The valve seat 4's central flow channel hole and the sealing plug 9 are a double-tapered sealing structure with a larger upper part and a smaller lower part. The sealing plug 9 includes a first-stage tapered outer cylindrical surface located at the top and a second-stage tapered outer cylindrical surface located below the first-stage tapered outer cylindrical surface, forming the second-stage taper of the sealing plug 9. This taper is matched with the central flow channel hole of the valve seat 4 to form a double-tapered sealing structure.

[0018] To suppress the formation of cavitation bubbles, the second-stage conical outer surface of the sealing plug 9 is provided with seven arc-shaped grooves 901, which are arranged axially at equal intervals. The grooves 901 form multi-stage throttling, allowing the fluid pressure to be released step by step, ensuring that the pressure at the constriction section is always higher than the saturation pressure, thus suppressing the formation of cavitation bubbles in principle. The arc-shaped grooves 901 can store a small amount of medium during sealing, forming an auxiliary sealing band and improving the sealing reliability under high pressure.

[0019] To achieve a better sealing effect, a metal spiral wound gasket 10 is provided between the valve seat 4 and the valve body 1, and between the valve body 1 and the valve cover 2. The metal spiral wound gasket 10 is resistant to high temperature and high pressure, and has higher elasticity and anti-aging properties compared with ordinary gaskets, ensuring that the valve has no external leakage. It is especially suitable for high temperature conditions and achieves a better sealing effect.

[0020] To achieve axial sealing of the valve stem 3, the packing seal assembly includes, from bottom to top, a packing pad 11, a combined packing 12, a packing sleeve 13, and a packing pressure plate 14. The packing pad 11 and the combined packing 12 are located in the stuffing box groove around the valve stem 3 on the upper part of the valve cover 2. The lower part of the packing sleeve 13 is located in the stuffing box groove and presses down on the combined packing 12. The packing pressure plate 14 presses down on the packing sleeve 13. The packing pressure plate 14 is connected and fixed to the upper end of the valve cover 2 by two sets of symmetrically arranged fully threaded studs and nuts. This facilitates axial sealing of the valve stem 3.

[0021] To better adapt to high-temperature and high-pressure operating conditions, valve body 1 and valve cover 2 are made of integral forged steel. Compared with cast valve body 1, forged steel has a denser structure, stronger pressure resistance and erosion resistance, making it more suitable for high-temperature and high-pressure operating conditions.

[0022] To achieve rigid coupling between the handwheel 15 and the valve stem 3, the handwheel drive assembly includes the handwheel 15, a lead screw seat, and a connecting flange 17. Four support columns 6 are fixed to the connecting flange 17 with hex bolts. The lower part of the lead screw seat is rotatably connected to the center hole of the connecting flange 17 via upper and lower secondary bearings 19. The upper end of the lead screw seat is connected to the handwheel 15 via a key 18. The upper end of the valve stem 3 has a lead screw section that mates with the lead screw seat. This achieves rigid coupling between the handwheel 15 and the valve stem 3, ensuring accurate torque transmission. When the handwheel 15 is rotated, the driving force is directly transmitted to the lead screw seat via the key 18, causing the lead screw seat to rotate. The lead screw seat then drives the valve stem 3 to move vertically.

[0023] The inlet flow channel and the vertical inner cavity of valve body 1 form a Y-shaped straight-through structure. Combined with the downward-sloping outlet flow channel, the fluid's own gravity and scouring effect reduce impurity deposition and achieve a "self-cleaning" function. In addition, this structure can reduce turbulence and energy loss, reduce the impact on the valve body 1 wall, and extend service life. Compared with single-cone or flat seals, the double-cone sealing structure increases the sealing contact area, improves the sealing performance under high pressure conditions, and the conical design facilitates automatic centering and reduces wear.

[0024] Example 2

[0025] Unlike the embodiments described above, the diameter of the outlet flow channel 102 is equal to the diameter of the inlet flow channel 101, and smaller than the inner cavity of the valve body 1 below the valve seat 4. In this embodiment, the diameter of the outlet flow channel 102 is 18 mm, and the diameter of the inner cavity of the valve body 1 below the valve seat 4 is 33 mm. This change in flow channel diameter allows the fluid to flow out more rapidly after the pressure inside the valve seat 4 has been reduced and stabilized, avoiding the formation of local high-pressure areas and reducing the risk of cavitation.

[0026] Example 3

[0027] Unlike embodiments one or two above, the valve stem 3 and valve core 8 are an integral structure. This integral structure reduces the number of parts, simplifies the structure, lowers maintenance complexity, eliminates assembly gaps between separate parts, prevents loosening due to vibration or impact, and improves sealing stability.

[0028] The above-described erosion-resistant manual drain valve is a specific embodiment of this utility model, demonstrating its substantial features and advancements. Based on actual usage needs, equivalent modifications in shape, structure, etc., can be made to it under the guidance of this utility model, all of which are within the scope of protection of this solution.

Claims

1. A kind of scouring resistant manual blowdown valve, including valve body, valve cover, valve stem, valve seat, sleeve and hand wheel drive assembly, the valve seat is located in the lower part of the inner cavity of the valve body, the sleeve is located on the valve seat in the valve body, the valve cover is located on the valve body, the upper surface of the valve cover is connected with hand wheel drive assembly by support column, the hand wheel drive assembly is located in the upper end of the valve stem, the valve stem passes through packing seal assembly in the upper end of valve cover, the rear of valve cover central hole and extends into sleeve in turn from top to bottom, the lower end of valve stem is equipped with valve core, the guide section of valve core is slidably matched with the inner wall of sleeve, the lower part of valve core is sealing plug, sealing plug is lowered to bottom, and the central flow passage hole of valve seat is closed, characterized in that: The valve body is provided with an obliquely downward inlet flow channel hole, which is communicated with the vertical valve body inner cavity above the valve seat; the other side of the valve body is provided with an obliquely downward outlet flow channel hole, the upper end of which is communicated with the vertical valve body inner cavity below the valve seat, and the center line of the outlet flow channel hole is downwardly deviated by 15-25 degrees from the center line of the inlet flow channel hole; the center flow channel hole of the valve seat and the sealing plug are matched two-taper sealing structure with the upper large and the lower small, the sealing plug includes the first level tapered outer cylindrical surface at the upper part and the second level tapered outer cylindrical surface below the first level tapered outer cylindrical surface, forming the two-taper sealing structure of the sealing plug and the center flow channel hole of the valve seat.

2. A scouring resistant manual drain valve according to claim 1, characterized in that: The diameter of the outlet flow channel hole is equal to the diameter of the inlet flow channel hole and smaller than the diameter of the valve body inner cavity below the valve seat.

3. A scouring resistant manual drain valve according to claim 1, wherein: The valve stem and the valve core are integrated structure.

4. A scouring resistant manual drain valve according to claim 1, wherein: The second level tapered outer cylindrical surface of the sealing plug is provided with 5-7 arc grooves, which are arranged at equal intervals in the axial direction.

5. A scouring resistant manual drain valve according to claim 1, wherein: The metal winding gasket is arranged between the valve seat and the valve body, and the metal winding gasket is arranged between the valve body and the valve cover.

6. A scouring resistant manual drain valve according to claim 1, wherein: The valve body and the valve cover are made of integral forged steel material.

7. A scouring resistant manual drain valve according to claim 1, wherein: The hand wheel driving assembly includes a hand wheel, a screw rod seat and a connecting flange, four support columns are connected and fixed with the connecting flange, the middle and lower part of the screw rod seat is rotatably connected with the center hole of the connecting flange through two level bearings, the upper end of the screw rod seat is connected with the hand wheel through a key, and the upper end of the valve stem is provided with a screw rod part matched with the screw rod seat.

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