CN212203137U - Low-side pressure reducing valve - Google Patents

Abstract

The utility model relates to a low other relief pressure valve, which comprises a valve body, the valve body on be provided with the valve gap, the valve body of valve gap below in be provided with the valve cage, seted up gaseous water conservancy diversion hole on the valve cage, be provided with the main valve seat in the valve body of valve cage below, be provided with the main valve lamella in the valve cage, first recess has been seted up to the bottom of main valve lamella, is provided with the guide cone in the first recess, the main valve seat top of first recess below is provided with first seal ring pad. The technical problem of inner leakage caused by incomplete closing due to leakage generated after the valve caused by direct impact under the pushing of high-speed steam flow and sealing surface of a cavitation valve core and a valve seat is solved. The utility model discloses adjust, convenient to use, be wide market prospect.

Description

Low-side pressure reducing valve

Technical Field

The utility model relates to a relief pressure valve field, concretely relates to low other relief pressure valve.

Background

The low bypass pressure reducing valve is an essential important core device in a bypass system of a large-scale reheating type steam turbine unit. The function is as follows: the reheated steam is firstly decompressed and then cooled before the unit is started, and then the condenser is led to the steam condenser without passing through the middle pressure cylinder and the low pressure cylinder, so that a steam circulation bypass is formed, the combustion of the boiler before the turbine rushes to rotate is guaranteed, the steam parameters of the unit are controlled, the starting time of the unit is shortened, the starting conditions are improved, and meanwhile the working medium can be recovered. The bypass systems are arranged in the large-scale reheating type steam turbine unit and are adjusting and protecting systems which are arranged to adapt to the conditions of starting, stopping and accidents of the unit. The low-side pressure reducing valve serves as a core component of a low-pressure bypass to become essential important equipment, and is used for reducing pressure and then cooling high-temperature high-pressure steam to cause a condenser without passing through a medium-pressure cylinder and a low-pressure cylinder, so that combustion of a boiler before the steam turbine rushes to rotate is guaranteed, the starting time of a unit is shortened, the starting condition is improved, working media are recovered, and noise is reduced. Before the steam turbine is flushed after the boiler is ignited or before the steam turbine is tripped, hot reheat steam bypasses the middle and low pressure cylinders of the steam turbine and is directly led to the condenser, so that the boiler reheater is protected from overpressure and overtemperature. And the system can meet the requirements of the unit on constant pressure and sliding pressure operation, balance the steam production of the boiler and the steam consumption of the steam turbine, stabilize the operation of the boiler and the steam turbine, and have safety regulation functions of starting, overflowing and the like.

The low other relief pressure valve is in the unit maintenance back, probably not leak in when just starting, nevertheless is along with the maintenance that exists in the pipeline after operation a period, all need weld usually in the maintenance process, and the welding slag often can drop to the pipeline in, at the operation in-process, along with the repeated operation of opening and closing of valve, high-pressure draught carries the welding slag and strikes the sealed face of case repeatedly, just interior hourglass has appeared after the valve action several times, and such condition appears repeatedly. After the valve with internal leakage is disassembled, the defects of erosion, damage and the like of the sealing surface are often found. In the prior art, in order to improve the sealing effect of the large-diameter valve, the large-diameter valve is mostly sealed in a line sealing mode, namely, the valve clack is contacted with the valve seat to form an annular sealing line, and the process is favorable for improving the sealing effect; because the boiler reheater and the system thereof are difficult to avoid generating welding slag impurities and the like even if the process is carefully paid after maintenance, the low bypass reducing valve is positioned at the tail end of a reheating system pipeline, the impurities enter a chamber of a valve when a unit starts a heating pipe, the impurities left on the inner surface of a reducing cage sleeve are brought to a sealing surface by a valve core when the valve is closed, the sealing surface of the valve core is used as a main flow-facing surface, and the leakage is generated after the valve is closed due to the fact that particles such as impurities are mixed in steam and the particles are directly impacted and corroded by high-speed steam flow and the sealing surface of the valve core and a valve seat, and the problem of internal leakage caused by the leakage.

Disclosure of Invention

The utility model provides a to prior art not enough, the utility model provides a can solve because of directly strikeing under the promotion of high-speed stream and produce the low other relief pressure valve of leaking behind the valve that the sealed face of cavitation case and disk seat arouses for overcome defect among the prior art.

The utility model adopts the technical proposal that: the utility model provides a low other relief pressure valve, includes the valve body, the valve body on be provided with the valve gap, the valve body of valve gap below in be provided with the valve cage, seted up gaseous water conservancy diversion hole on the valve cage, be provided with the main valve seat in the valve body of valve cage below, be provided with the main valve lamella in the valve cage, first recess has been seted up to the bottom of main valve lamella, is provided with the guide cone in the first recess, the main valve seat top of first recess below is provided with first seal ring and fills up.

Preferably, the first sealing ring gasket is of a circular truncated cone-shaped annular structure, the first groove is of a circular truncated cone-shaped groove-shaped structure, the slope of the outer side surface of the first sealing ring gasket is not smaller than the slope of the side wall of the first groove, the first sealing ring gasket is fixedly connected with the main valve flap, and the main valve flap on the outer side of the first sealing ring gasket is provided with a second groove.

Preferably, valve gap top be provided with the pneumatic cylinder, the valve gap below is provided with connects the arch, the pneumatic cylinder includes cylinder body and telescopic link, connect protruding and the equal suit of valve gap on the telescopic link of pneumatic cylinder, be provided with connecting device on the main valve lamella, connect bellied bottom and seted up the third recess, the cover is equipped with the second seal ring pad on the telescopic link of the pneumatic cylinder in the third recess, the telescopic link swing joint of second seal ring pad and pneumatic cylinder, second seal ring pad and third recess threaded connection.

Preferably, the guide cone comprises a first portion and a second portion, the first portion is located above the bottom surface of the main valve flap, the first portion is of a cylindrical structure, the second portion is located below the bottom surface of the main valve flap, and the second portion is of a truncated cone structure.

Preferably, the first sealing ring gasket adopts an annular structure, an airflow through hole is formed in the main valve seat, the airflow through hole and an inner hole of the first sealing ring gasket are located on the same axis, the first sealing ring gasket is located on the outer side of the guide cone, and the inner diameter of the first sealing ring gasket is not larger than the maximum diameter of the guide cone.

Preferably, the top of the valve cage is provided with a first connecting groove, the first connecting groove is of an annular groove-shaped structure, a first connecting ring is sleeved in the first connecting groove, the top surface of the first connecting ring is fixedly connected with the bottom surface of the valve cover, and the first connecting groove is in threaded connection with the first connecting ring.

Preferably, the second groove is of an annular groove-shaped structure, and the inner diameter of the second groove is not smaller than the outer diameter of the bottom of the first sealing ring gasket.

Preferably, connecting device include the second spread groove, the second spread groove is located the top of main valve lamella, the free end of the telescopic link of pneumatic cylinder is located the second spread groove, the fixed stopper that is provided with on the free end of the telescopic link of pneumatic cylinder, the cover is equipped with the second go-between on the telescopic link of the pneumatic cylinder of stopper top, second go-between and second spread groove threaded connection.

The utility model has the advantages that: first, the utility model discloses a first recess has been seted up in the bottom of main valve lamella, and first recess internal fixation is provided with the guide cone, and the main valve seat top of first recess below is provided with first sealing ring pad, has guaranteed that this product has at least partly case sealing face can directly not receive the impact of high-speed stream, thereby has solved because of direct impact under the promotion of high-speed stream and the cavitation case produces the leakage behind the valve that the sealing face arouses with the disk seat, causes to close not tight interior hourglass problem.

Secondly, the guide cone include first portion and second part, the first portion be located main valve lamella bottom surface top, the first portion adopt cylindric structure, the diameter of first portion and the internal diameter of first seal ring pad cooperate, under the closure state, first portion and the airtight laminating of first seal ring pad, increased the sealed face of second in other words, improved sealed effect. The second part is located below the bottom surface of the main valve flap, the second part is in a circular truncated cone-shaped structure, the structure is favorable for guiding high-pressure steam to pass through the lower airflow through holes to be discharged out of the product, and the circular truncated cone-shaped structure is adopted by the second part, so that direct contact between the high-pressure steam and the first part is reduced, loss of the first part is reduced, and durability of the product is improved.

Finally, because the valve cage directly receives the direct impact of high temperature high pressure steam for a long time, often need change when opening the machine, for the change of convenient valve cage, this product is in the top of valve cage seted up first connecting groove, first connecting groove adopts annular groove-shaped structure, and first connecting ring is equipped with to first connecting groove endotheca, the bottom surface fixed connection of the top surface of first connecting ring and valve gap, first connecting groove and first connecting ring threaded connection.

The utility model has the advantages of simple structure, convenient operation, design benefit has improved work efficiency greatly, has fine social and economic benefits, is the product of easily using widely.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a partially enlarged schematic view of detail a of fig. 1.

Fig. 3 is a partially enlarged schematic view of detail B of fig. 1.

Fig. 4 is an enlarged partial view of detail C of fig. 1.

Fig. 5 is a schematic view of the closed state of the present invention.

Detailed Description

As shown in fig. 1, 2, 3, 4, a low side relief pressure valve, includes valve body 1, valve body 1 on be provided with valve gap 2, valve gap 2 and valve body 1 pass through the bolt fastening, valve body 1 of valve gap 2 below in be provided with valve cage 3, valve cage 3 and main valve seat 5 swing joint have been seted up gaseous water conservancy diversion hole 4 on the valve cage 3, be provided with main valve seat 5 in the valve body 1 of valve cage 3 below, main valve seat 5 and valve body 1 fixed connection, be provided with main valve lamella 6 in the valve cage 3, first recess 7 has been seted up to main valve lamella 6's bottom, first recess 7 internal fixation is provided with guide cone 8, main valve seat 5 top below first recess 7 is provided with first seal ring pad 9.

2 tops of valve gap be provided with pneumatic cylinder 11, the fixed connection arch 12 that is provided with in 2 below of valve gap, pneumatic cylinder 11 includes cylinder body and telescopic link, the cylinder body of pneumatic cylinder 11 is fixed in valve gap 2 tops, connect protruding 12 and the equal suit of valve gap 2 on the telescopic link of pneumatic cylinder 11, be provided with connecting device on the main valve lamella 6, third recess 13 has been seted up to the bottom of connecting protruding 12, the cover is equipped with the sealed ring of second pad 14 on the telescopic link of pneumatic cylinder 11 in the third recess 13, connect protruding 12 and the sealed ring of second pad 14 and equally divide respectively with the telescopic link swing joint of pneumatic cylinder 11, the sealed ring of second pad 14 and the 13 threaded connection of third recess. The connecting device comprises a second connecting groove 18, the second connecting groove 18 is located at the top of the main valve flap 6, the free end of the telescopic rod of the hydraulic cylinder 11 is located in the second connecting groove 18, a limiting block 19 is fixedly arranged at the free end of the telescopic rod of the hydraulic cylinder 11, a second connecting ring 20 is sleeved on the telescopic rod of the hydraulic cylinder 11 above the limiting block 19, and the second connecting ring 20 is in threaded connection with the second connecting groove 18.

In order to reduce the influence of solid particles such as welding slag carried in steam on the main valve flap 6 and the guide cone 8 and reduce the damage to the sealing surface of the product caused by the solid particles in the closed state of the product and the erosion damage to the sealing surface of the product as much as possible, the first sealing ring gasket 9 adopts a circular truncated cone-shaped annular structure, the first groove 7 adopts a circular truncated cone-shaped groove-shaped structure, the gradient of the outer side surface of the first sealing ring gasket 9 is not smaller than the gradient of the side wall of the first groove 7, the first sealing ring gasket 9 is fixedly connected with the main valve flap 6, and the main valve flap 6 on the outer side of the first sealing ring gasket 9 is provided with a second groove 10. Along with the most solid particles of high-pressure air flow discharge this product along with high-pressure air flow, a small part of solid particles can not enter into second recess 10 along with the multiple bounce-back of high-pressure air flow discharge this product through first seal ring pad 9, guide cone 8, main valve lamella 6 and main valve seat 5 contact surface combines air current power to the clearance of waiting to overhaul in time, second recess 10 preferably adopt annular groove form structure, the internal diameter of second recess 10 is not less than the external diameter of first seal ring pad 9 bottom, the internal diameter of preferred second recess 10 equals with the external diameter of first seal ring pad 9 bottom so more be favorable to solid particles to contact the side of first seal ring pad 9 and directly fall to second recess 10 in.

In order to further improve the sealing effect, the first sealing ring gasket 9 of the product adopts an annular structure, the main valve seat 5 is provided with an airflow passing hole 15, the airflow passing hole 15 and an inner hole of the first sealing ring gasket 9 are positioned on the same axis, the first sealing ring gasket 9 is positioned on the outer side of the guide cone 8, and the inner diameter of the first sealing ring gasket 9 is not larger than the maximum diameter of the guide cone 8. The guide cone 8 comprises a first part and a second part, the first part is located above the bottom surface of the main valve flap 6, the first part is of a cylindrical structure, the diameter of the first part is matched with the inner diameter of the first sealing ring gasket 9, the first part is closely attached to the first sealing ring gasket 9 in a closed state, a second sealing surface is equivalently added, and the sealing effect is improved. The second part is positioned below the bottom surface of the main valve flap 6, the second part adopts a circular truncated cone-shaped structure, the structure is favorable for guiding high-pressure steam to pass through the lower airflow through holes 15 to be discharged out of the product, and the circular truncated cone-shaped structure is further favorable for reducing the direct contact between the high-pressure steam and the first part, so that the loss of the first part is reduced, and the durability of the product is improved.

Because the valve cage 3 directly receives the direct impact of high temperature high pressure steam for a long time, often need change when opening the machine, for the change of convenient valve cage 3, this product is in the top of valve cage 3 seted up first connecting groove 16, first connecting groove 16 adopts annular groove-shaped structure, first connecting ring 17 is equipped with to first connecting groove 16 endotheca, the bottom surface fixed connection of the top surface of first connecting ring 17 and valve gap 2, first connecting groove 16 and first connecting ring 17 threaded connection.

The use method of the product is as follows: as shown in fig. 1, 2, 3 and 4, during the closing process, the hydraulic cylinder 11 drives the main valve flap 6 and the guide cone 8 to move downwards, in the process, high-pressure steam enters the valve cage 3 through the gas guide hole 4, the high-pressure steam contacts the second part of the guide cone 8, and passes through the product through the gas flow hole 15 by being guided by the second part of the guide cone 8, when the bottom surface of the main valve flap 6 contacts the top surface of the main valve seat 5, the closed state is achieved, at the moment, a first closing surface is formed between the bottom surface of the main valve flap 6 and the top surface of the main valve seat 5, and a second closing surface is formed between the first part of the guide cone 8 and the first sealing ring gasket 9.

Because the valve cage 3 body is provided with the plurality of gas diversion holes 4, the gas diversion holes have the solid particle screening function, overlarge solid particles can be filtered on the outer side of the valve cage 3, when the valve cage is opened, the hydraulic cylinder 11 drives the main valve flap 6 and the guide cone 8 to move upwards, in the process, the solid particles staying in the valve cage 3 can partially enter the inner side of the valve cage 3 along with high-pressure steam due to overlarge instantaneous airflow, absolute partial solid particles entering the inner side of the valve cage 3 can be discharged out of the product along with the high-pressure steam, and residual micro solid particles enter the second groove 10 to be temporarily stored under the comprehensive action of the driving force of the high-pressure steam combined with the outer side wall of the first sealing ring gasket 9, so that the damage of the bottom surface of the main valve flap 6 or the top surface of the main valve seat 5 caused by staying at the top of the top surface of the main valve seat.

Through the embodiment, the problem of leakage caused by direct impact under the pushing of high-speed steam flow and leakage generated after the valve caused by the sealing surface of the cavitation valve core and the valve seat, and the problem of internal leakage caused by unclosed closing is solved. In addition, the heat consumption rate is increased by 4.0kJ/kWh and the coal consumption rate is increased by about 0.37g/kWh per 1t/h of steam leakage of the low-side pressure reducing valve of the 300 MW-grade subcritical unit. The generated standard coal amount is calculated by referring to the annual generating capacity of the unit and the coal consumption influenced by the steam leakage of the low side pressure reducing valve by 1t/h, and the generated coal cost can be obtained by combining the average standard coal unit price in the market. However, the steam quantity of the internal leakage of the low-side pressure reducing valve in actual production is not only 1t/h, so that the internal leakage is eliminated after the development and implementation, and considerable direct economic benefit can be generated.

In addition, the leakage quantity is counted according to the valve with leakage fault

Name (R)	Valve with leakage fault	Average air leakage	Average heat loss
				Adopts a traditional structure	95 are provided with	3t/h	6.0KJ/kWh
The product	9 are provided with	0.2t/h	0.3KJ/kWh

The utility model discloses a satisfy in a low other relief pressure valve of relief pressure valve field worker needs, make the utility model discloses extensive market prospect has.

Claims (8)

1. The utility model provides a low other relief pressure valve, includes valve body (1), valve body (1) on be provided with valve gap (2), its characterized in that: the valve body (1) below the valve cover (2) is internally provided with a valve cage (3), the valve cage (3) is provided with a gas guide hole (4), the valve body (1) below the valve cage (3) is internally provided with a main valve seat (5), the valve cage (3) is internally provided with a main valve flap (6), the bottom of the main valve flap (6) is provided with a first groove (7), the first groove (7) is internally provided with a guide cone (8), and the top of the main valve seat (5) below the first groove (7) is provided with a first sealing ring gasket (9).

2. The low side relief valve of claim 1, wherein: first sealing ring pad (9) adopt round platform shape annular structure, first recess (7) adopt round platform shape groove-shaped structure, the slope of first sealing ring pad (9) lateral surface is not less than the slope of first recess (7) lateral wall, first sealing ring pad (9) and main valve lamella (6) fixed connection, second recess (10) have been seted up on main valve lamella (6) in first sealing ring pad (9) outside.

3. The low side relief valve of claim 1, wherein: valve gap (2) top be provided with pneumatic cylinder (11), valve gap (2) below is provided with connects protruding (12), pneumatic cylinder (11) are including cylinder body and telescopic link, connect protruding (12) and valve gap (2) all suit on the telescopic link of pneumatic cylinder (11), be provided with connecting device on main valve lamella (6), third recess (13) have been seted up to the bottom of connecting protruding (12), the cover is equipped with second seal ring pad (14) on the telescopic link of pneumatic cylinder (11) in third recess (13), the telescopic link swing joint of second seal ring pad (14) and pneumatic cylinder (11), second seal ring pad (14) and third recess (13) threaded connection.

4. The low side relief valve of claim 1, wherein: the guide cone (8) comprises a first part and a second part, the first part is positioned above the bottom surface of the main valve flap (6), the first part adopts a cylindrical structure, the second part is positioned below the bottom surface of the main valve flap (6), and the second part adopts a circular truncated cone-shaped structure.

5. The low side relief valve of claim 1, wherein: first sealing ring pad (9) adopt cyclic annular structure, be provided with air current through hole (15) on main valve seat (5), the hole of air current through hole (15) and first sealing ring pad (9) is located same axis, first sealing ring pad (9) are located the outside of guide cone (8), the internal diameter of first sealing ring pad (9) is not more than the maximum diameter of guide cone (8).

6. The low side relief valve of claim 1, wherein: the top of valve cage (3) seted up first connecting groove (16), first connecting groove (16) adopt annular groove-shaped structure, first connecting ring (17) are equipped with in first connecting groove (16) endotheca, the bottom surface fixed connection of the top surface of first connecting ring (17) and valve gap (2), first connecting groove (16) and first connecting ring (17) threaded connection.

7. The low side relief valve of claim 2, wherein: the second groove (10) is of an annular groove-shaped structure, and the inner diameter of the second groove (10) is not smaller than the outer diameter of the bottom of the first sealing ring gasket (9).

8. A low by-pass pressure relief valve as defined in claim 3, wherein: the connecting device comprises a second connecting groove (18), the second connecting groove (18) is located at the top of the main valve clack (6), the free end of a telescopic rod of the hydraulic cylinder (11) is located in the second connecting groove (18), a limiting block (19) is fixedly arranged at the free end of the telescopic rod of the hydraulic cylinder (11), a second connecting ring (20) is sleeved on the telescopic rod of the hydraulic cylinder (11) above the limiting block (19), and the second connecting ring (20) is in threaded connection with the second connecting groove (18).

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