Inlet high-pressure heater three-way valve

Abstract

The utility model relates to an inlet high-pressure heater three-way valve, which belongs to the field of valves, and comprises a valve body, a valve clack, a valve rod, a valve cover and an actuating mechanism, the valve body is provided with an inlet channel, an outlet channel and a bypass channel, and a lower valve seat and an upper valve seat are respectively arranged between the inlet channel and the outlet channel and between the inlet channel and the bypass channel. The upper valve seat is installed in a valve cavity between the inlet channel and the bypass channel through a bolt, a pressing ring and a four-piece ring. The check valve is characterized in that an inner hole of the four-piece ring is provided with a radial inner step, a mutual positioning structure is formed between the bolt and the four-piece ring, the outer side of a hexagonal screw head of the bolt can prevent the four-piece ring from falling out of a circular groove in the inner wall of the valve cavity, and the radial inner step of the four-piece ring can prevent the bolt from loosening or falling out due to medium scouring. And the product has the advantages of good use reliability, long service life and the like.

Description

Technical Field

[0001] The utility model belongs to the field of valves, and particularly relates to a high-pressure heater three-way valve. The utility model is applicable to the bypass valve of a high-pressure heater of a large-scale thermal power engine set. Background Art

[0002] The high-pressure heater inlet three-way valve is installed at the inlet of the high-pressure heater of the thermal power engine set and is used to feed water to the high-pressure boiler through the bypass when the high-pressure heater fails, so as to protect the safe water supply of the high-pressure boiler. The structure of the existing high-pressure heater inlet three-way valve generally includes a valve body, a valve flap, a valve stem, a valve cover, and an actuator. The valve body has an inlet, an outlet, and a bypass port. A lower valve seat and an upper valve seat are respectively arranged at the inlet, the outlet, and the bypass port. The valve flap is installed between the lower valve seat and the upper valve seat through the valve stem, and sealing surfaces that cooperate with the upper valve seat and the lower valve seat are respectively arranged on its upper and lower planes. In order to accurately set the axial distance between the upper valve seat and the lower valve seat, the upper valve seat of the existing product is generally installed in the valve cavity between the inlet and the bypass port by bolts and four split rings. For example, the built-in high-pressure piston-driven high-pressure heater three-way valve with the publication number CN203770716U is composed of a valve body, a valve flap, an upper valve seat, a valve cover, a high-pressure piston, a spring energy storage ring, a throttle sleeve, a travel switch, etc. The upper valve seat adopts a pressure self-tightening seal structure and is composed of a four-piece ring, a self-sealing ring, a pressure ring, a pressing plate, and a hexagon head bolt. When the high-pressure heater fails, the valve is switched from the main path to the bypass to open, the high-pressure heater is cracked, and the feed water enters the boiler through the bypass. Its disadvantages are as follows: during use, when the high-pressure water flow in the bypass water supply state passes through the upper valve seat, the fluid vortex impacts the bolts, which will cause the bolts to loosen or even fall off, and the reliability of the product in use is very poor, and the service life is short. Content of the Utility Model

[0003] Aiming at the disadvantages of the existing technology, the utility model provides an inlet high-pressure heater three-way valve with a firmly installed upper valve seat, which is not easily loosened or fallen off by the erosion of the medium, and has good reliability and long service life in use.

[0004] The technical solution of the utility model is as follows:

[0005] An inlet high-pressure heater three-way valve includes a valve body, a valve flap, a valve stem, a valve cover, and an actuator. The valve body has an inlet passage, an outlet passage, and a bypass passage. A lower valve seat and an upper valve seat are respectively arranged between the inlet passage and the outlet passage and the bypass passage. The valve flap is installed between the lower valve seat and the upper valve seat through the valve stem, and sealing surfaces that cooperate with the upper valve seat and the lower valve seat are respectively provided on its upper and lower planes. The upper valve seat is installed in the valve cavity between the inlet passage and the bypass passage by bolts, a pressing ring, and a four-way split ring. A sealing ring is tightly installed between the outer circular surface of the upper part of the upper valve seat and the valve cavity by the pressing ring. The four-way split ring is composed of four snap rings spliced into an integral circular ring and is installed in the circular groove on the inner wall of the valve cavity above the pressing ring; The feature is that a radial inner step is arranged in the inner hole of the four-way split ring to form a limiting mechanism with the bolt; The annular table surface of the radial inner step is in clearance fit with the upper end surface of the bolt hexagon head to form an upper limit for the bolt; The outer circumference of the bolt hexagon head touches the inner circular wall below the radial inner step to form a radial limit for the four-way split ring; The lower end surface of the four-way split ring is press-fitted on the upper end surface of the pressing ring, and an axial bolt installation notch is made in the radial inner step of one of the snap rings of the four-way split ring.

[0006] In the above technical solution, a flexible connection mechanism is adopted between the valve stem and the valve flap. The flexible connection mechanism is composed of disc springs respectively arranged between the lower end surface and the upper ring surface of the radial shoulder at the lower end of the valve stem and the inner wall of the valve flap installation cavity.

[0007] In the above technical solution, a valve stem guide ring is arranged at the center of the inner hole of the upper valve seat.

[0008] The beneficial effects of the present utility model compared with the prior art are as follows: A mutual limiting device is formed between the four-way split ring and the bolt. The outer side of the outer hexagon head of the bolt can prevent the four-way split ring from falling out of the circular groove on the inner wall of the valve cavity, and the radial inner step of the four-way split ring can prevent the bolt from being loosened or falling out due to medium erosion. The four-way split ring and the bolt are installed firmly and reliably, and have the advantages of good product use reliability and long service life. Description of the Drawings

[0009] Figure 1 It is a structural schematic diagram of the present utility model.

[0010] Figure 2 It is the present utility model Figure 1 The installation structural schematic diagram between the valve seat and the valve cavity in the middle.

[0011] Figure 3 It is the present utility model Figure 2 The bottom view of the four-way split ring in the middle.

[0012] In the figure: 1 valve body, 2 lower valve seat, 3 valve flap, 4 disc spring, 5 valve flap cover, 6 valve stem, 7 upper valve seat, 8 sealing ring, 9 compression ring, 10 four-way split ring, 11 bypass channel, 12 inlet channel, 13 valve cover, 14 self-sealing ring, 15 four-way snap ring, 16 support plate, 17 packing seat ring, 18 packing, 19 packing gland, 20 packing pressing plate, 21 anti-rotation splint, 22 bracket, 23 axial bolt installation notch, 24 radial inner step, 25 bolt, 26 valve stem guide ring, 27 outlet channel. Detailed implementation mode

[0013] As Figure 1 shown in the inlet high-pressure heater three-way valve, including valve body 1, valve flap 3, valve stem 6, valve cover 13, and actuator. The valve body 1 has an inlet channel 12, an outlet channel 27, and a bypass channel 11. A lower valve seat 2 and an upper valve seat 7 are respectively arranged between the inlet channel 12 and the outlet channel 27 and the bypass channel 11, that is, a lower valve seat 2 is arranged between the inlet channel 12 and the outlet channel 27, and an upper valve seat 7 is arranged between the inlet channel 12 and the bypass channel 11. The valve flap 3 is installed between the lower valve seat 2 and the upper valve seat 7 through the valve stem 6, and sealing surfaces that cooperate with the upper valve seat 7 and the lower valve seat 2 are respectively provided on its upper and lower planes. The upper valve seat 7 is installed in the valve cavity between the inlet channel 12 and the bypass channel 11 by bolts 25, compression rings 9, and four-way split rings 10. A sealing ring 8 is tightly installed between the outer circular surface of the upper part of the upper valve seat 7 and the valve cavity by the compression ring 9. The four-way split ring 10 is installed in the circular groove on the inner wall of the valve cavity above the compression ring 9. A lower step is arranged on the outer circular surface of the upper valve seat 7 below the sealing ring 8 to cooperate with the upper step on the inner wall of the valve cavity to form an axial limiting device for the upper valve seat 7; its feature is that: a radial inner step 24 is arranged in the inner hole of the four-way split ring 10 to form a limiting mechanism with the bolt 25; the annular table surface of the radial inner step 24 abuts against the upper end surface of the hexagonal head of the bolt 25, constituting an upper limit for the bolt 25, restricting the axial movement of the bolt 25 and preventing the bolt 25 from being loosened or dropped due to fluid erosion; the outer circumference of the hexagonal head of the bolt 25 abuts against the inner circular wall below the radial inner step 24, constituting a radial limit for the four-way split ring 10 and preventing the four-way split ring 10 from falling out of the circular groove in the valve cavity. The lower end surface of the four-way split ring 10 is press-fitted on the upper end surface of the compression ring 9, as Figure 2 shown. An axial bolt installation notch 23 is made in the radial inner step 24 of one of the snap rings of the four-way split ring 10, so that the bolt 25 can be installed into the compression ring 9 and the upper valve seat 7 from the axial bolt installation notch 23, as Figure 3 shown. After installing one bolt 25, rotate the snap ring so that its axial bolt installation notch 23 is aligned with another installation hole of the compression ring 9 and the upper valve seat 7, and install the bolt 25 into this installation hole. By analogy, install the bolts 25 into the respective installation holes in the circumferential direction of the compression ring 9 and the upper valve seat 7 to complete the installation of the compression ring 9 and the upper valve seat 7.

[0014] A flexible connection mechanism is adopted between the valve stem 6 and the valve disc 3. The flexible connection mechanism is composed of disc springs 4 respectively arranged between the lower end face and the upper ring face of the radially protruding shoulder at the lower end of the valve stem 6 and the upper and lower walls of the valve disc installation cavity. The valve disc installation cavity is composed of a valve disc cover 5 installed in the central hole at the upper end of the valve disc 3, and the valve disc 3 is axially elastically installed on the radially protruding shoulder at the lower end of the valve stem 6.

[0015] A valve stem guide ring 26 is arranged at the center of the inner hole of the upper valve seat 7 to realize the radial positioning of the valve stem 6 and improve the stability of the axial movement of the valve stem 6.

[0016] A pressure self-sealing structure is adopted between the valve cover 13 and the valve body 1. The pressure self-sealing structure is composed of a self-sealing ring 14, a four-way snap ring 15, a support plate 16 and bolts / nuts; a packing sealing device is arranged between the valve cover 13 and the valve stem 6. The packing sealing device is composed of a packing seat ring 17, packing 18, a packing gland 19 and a packing pressing plate 20; the actuator is installed on the upper end face of the middle cavity of the valve body 1 through a bracket 22, and its structure can adopt an electric actuator, a hydraulic actuator or a pneumatic actuator. In this embodiment, an electric actuator is adopted; an anti-rotation clamping plate 21 is arranged on the valve stem 6, and the anti-rotation clamping plate 21 and the guide ribs on the bracket 22 cooperate with each other to form an anti-rotation device to prevent the valve stem 6 from rotating.

Claims

1. An inlet high-pressure three-way valve, comprising a valve body (1), a valve disc (3), a valve stem (6), a valve cover (13), and an actuator, wherein the valve body (1) has an inlet channel (12), an outlet channel (27), and a bypass channel (11), a lower valve seat (2) and an upper valve seat (7) are respectively arranged between the inlet channel (12), the outlet channel (27), and the bypass channel (11), and the valve disc (3) is installed between the lower valve seat (2) and the upper valve seat (7) through the valve stem (6). The upper and lower planes of the valve are respectively provided with sealing surfaces that cooperate with the upper valve seat (7) and the lower valve seat (2); the upper valve seat (7) is installed in the valve cavity between the inlet passage (12) and the bypass passage (11) by means of bolts (25), a clamping ring (9), and a four-open ring (10); a sealing ring (8) is installed between the upper outer surface of the upper valve seat (7) and the valve cavity by means of the clamping ring (9); and the four-open ring (10) is installed in a circular groove on the inner wall of the valve cavity above the clamping ring (9); the valve is characterized in that: A radial inner step (24) and a bolt (25) are provided in the inner hole of the four-open ring (10) to form a limiting mechanism; the annular table surface of the radial inner step (24) contacts the upper end surface of the hexagonal screw head of the bolt (25) to form an upper limit position of the bolt (25); the outer periphery of the hexagonal screw head of the bolt (25) contacts the inner circular wall below the radial inner step (24) to form a radial limit position of the four-open ring (10); the lower end surface of the four-open ring (10) is press-fitted on the upper end surface of the clamping ring (9), and an axial bolt installation notch (23) is formed in the radial inner step (24) of one of the retaining rings of the four-open ring (10).

2. The inlet high pressure three-way valve according to claim 1 is characterized in that: A flexible connection mechanism is used between the valve stem (6) and the valve disc (3), the flexible connection mechanism comprising disc springs (4) respectively arranged between the lower end surface and upper annular surface of the radial boss at the lower end of the valve stem (6) and the upper and lower walls of the valve disc installation cavity.

3. The inlet high pressure three-way valve according to claim 1 or 2, characterized in that: A valve stem guide ring (26) is arranged at the center of the inner hole of the upper valve seat (7).

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