CN209622073U - A pneumatic single-seat regulating valve - Google Patents

Abstract

The utility model relates to a kind of Pneumatic single-seat regulating valves, include pneumatic diaphragn actuating mechanism, bracket and valve body, pneumatic diaphragn actuating mechanism is connected by bracket with valve body, valve body includes filler, gland, valve deck, valve rod, press cage, spool, valve body, valve seat, valve seat is arranged in valve body, spool is set in pressure cage, spool is connected on valve rod, valve stem sleeve is equipped with valve deck, valve rod passes through valve deck and is connected with pneumatic diaphragn actuating mechanism, spool is moved up and down along pressure cage by valve rod and seals and be detached from valve seat, it is equipped between valve seat and spool and leniently arrives the narrow sealing surface in step type, every layer sealing surface is attached with seal washer, the narrow sealing surface in step type is leniently arrived by being arranged on valve seat, enable spool self-adapting seal in abrasion, the service life for improving spool passes through the funnel type throttling of pressure cage The use of slot considerably reduces the noise of medium generation, improves the service life of valve.

Description

A pneumatic single-seat regulating valve

technical field

The utility model relates to a single-seat regulating valve, in particular to a pneumatic single-seat regulating valve.

Background technique

In the gas and liquid (fluid) pipelines, multiple valves must be set for control, to control the opening, closing or opening degree of the pipeline, etc., so as to generate corresponding actions, so that the pipeline can be opened as required and the degree of opening can be controlled. Or closed, gas, liquid (fluid), etc. pass through the control valve. However, the high-pressure regulating valve used in petroleum, chemical and other fields has a high pressure difference, which puts forward higher requirements for the sealing structure between the valve body and the valve seat, otherwise there will be poor sealing effect, easy leakage, and wear and tear. And reduce the service life and other defects. For low-pressure control valves used in other pipelines, the pressure difference between the two ends of the valve body is small, which reduces the requirements for the fit, sealing, and smooth operation of the valve body. A single-seat control valve can be used to realize the control function.

The single-seat control valve is a top-guided control valve with small pressure drop loss, large flow rate, wide adjustable range, high accuracy of the flow characteristic curve, large spool guide area, good shock resistance, and is widely used. The valve includes electric single-seat control valve and pneumatic single-seat control valve. The pneumatic single-seat control valve includes pneumatic film actuator, bracket, packing, packing gland, bonnet, valve stem, pressure cage, valve core, valve body As well as the valve seat located in the valve body, it has the advantages of simple control, quick response, and intrinsic safety, and does not need to take additional explosion-proof measures. Problems such as erosion, vibration, noise, and sealing are more serious, and the flow rate increases with the change of the stroke, and the regulation performance is also reduced. The actual service life of the valve is greatly reduced due to continuous operation under high pressure, high temperature, and high flow rate.

Utility model content

The technical problem to be solved by the utility model is to address the above-mentioned deficiencies in the prior art,

Provided is a pneumatic single-seat control valve with low noise, corrosion resistance, good sealing performance and long service life.

In order to achieve the above purpose, the utility model provides the following technical solutions: a pneumatic single-seat regulating valve, including a pneumatic diaphragm actuator, a bracket and a valve body, and the pneumatic diaphragm actuator is connected to the valve body through a bracket, which is characterized in that : The valve body includes packing, packing gland, valve cover, valve stem, pressure cage, valve core, valve body, valve seat, the valve seat is arranged in the valve body, and the valve core is sleeved in the pressure cage , the valve core is connected to the valve stem, and the valve stem is covered with a valve cover, and the valve stem passes through the valve cover to connect with the pneumatic diaphragm actuator, and the valve cover and the valve stem are connected through a packing gland Sealed with packing, the valve core moves up and down along the pressure cage through the valve rod to seal and separate from the valve seat, and the contact surface between the valve seat and the valve core is provided with a stepped sealing surface from wide to narrow, Sealing gaskets are attached to each sealing surface.

With the above technical scheme, there are medium inlet and medium outlet on both sides of the valve body, and the medium inlet and medium outlet are connected with the valve seat to form a flow channel for medium circulation. The flow channel is an S-shaped structure, and the valve seat is equipped with a pressure cage. There is a valve core that moves up and down with the valve stem. One end of the valve stem passes through the valve core and is fixedly connected to the valve core through a nut, and the other end passes through the valve cover to connect with the pneumatic membrane actuator structure. If there is a gap, add packing in the gap between the valve cover and the valve stem. The packing can be PTFE V-shaped packing or PTFE asbestos, and then seal it with the packing gland to make the air seal between the valve stem and the valve cover. The entire regulating valve is convenient to open and close, and the operation is simple, but because the spool inside the valve body is under the impact of fluid for a long time, especially in the environment with corrosive fluid, the spool will wear out, but by adopting pneumatic actuation The device pushes the valve stem, and the stroke of the valve stem is fixed, resulting in the inability to produce a tight fit between the valve core and the valve seat, so that a new valve core needs to be replaced, which reduces the durability of the valve and the overall sealing accuracy. There are three layers of stepped sealing surfaces from wide to low on the top, and the sealing gaskets are fastened on each sealing surface so that the valve core is worn during the corrosion process during use, but due to the setting of the three-layer sealing surface , so that the circular valve core can still enter the sealing surface of the next layer for sealing after wear and tear, which improves the sealing performance of the regulating valve and increases the service life of the valve core.

The above-mentioned pneumatic single-seat control valve can be further configured as follows: the side wall of the pressure cage is provided with several throttling grooves for the circulation of the medium in the valve body, and the throttling grooves are funnel-shaped.

With the above technical solution, several throttling grooves are provided on the side wall of the pressure cage for the medium circulation in the valve body, which makes the opening and closing of the regulating valve easier, and the throttling grooves adopt a funnel-shaped structure, so that when the medium is opened from the valve core, some The medium will enter the large hole from the small hole at the bottom of the throttling groove. After the medium is sprayed in with the throttling groove, the medium will collide with each other in the center of the pressure cage. The collision will consume energy and play a buffer role. At the same time, the high flow rate reduces the possibility of vortex formation, thereby greatly reducing the noise generated by the medium, improving the anti-cavitation and anti-flash performance, and increasing the service life of the valve.

The above-mentioned pneumatic single-seat control valve can be further configured as follows: the valve stem is provided with a positioning scale indicating the flow rate of the fluid, and the bracket is provided with a scale corresponding to the positioning scale.

With the above technical scheme, when the valve core is at the highest position, the positioning scale indicates the highest scale of the scale, and the valve core is separated from the valve seat; when the valve core is at the lowest position, the positioning scale indicates the lowest scale of the scale, and the valve The core seal valve seat 2, when in use, drives the valve stem through the pneumatic film actuator, so that the valve core moves up and down in the pressure cage and tightly fits with the valve seat to achieve opening and closing. The stroke of the valve stem is displayed through the positioning scale provided on the valve stem, and then the fluid flow rate is indicated, so that the fluid flow rate can be adjusted in real time, and the overall reliability is improved.

The above-mentioned pneumatic single-seat control valve can be further configured as follows: a ceramic protective layer is attached to the inner wall of the valve core, and the valve core is made of stainless steel.

With the above technical scheme, the inner wall of the valve core is attached with a ceramic protective layer to ensure the wear resistance and corrosion resistance of the valve core. lifespan.

The above-mentioned pneumatic single-seat control valve can be further configured as follows: a sealing gasket is provided between the valve seat and the valve body.

Adopting the above technical scheme, the valve seat and the valve body adopt a snap-in type. When the valve cover is pressed, the valve core and the valve seat are automatically centered, and the assembly and disassembly are simple and convenient. The sealing performance of the valve seat is further improved to prevent medium leakage.

The beneficial effect of the utility model is: by setting a stepped sealing surface from wide to narrow on the valve seat, the valve core can be self-adaptively sealed during wear and tear, and the service life of the valve core is improved. The use of the throttling groove greatly reduces the noise generated by the medium, improves the anti-cavitation and anti-flash performance, and increases the service life of the valve.

Below in conjunction with accompanying drawing and embodiment the utility model is described in further detail.

Description of drawings

Fig. 1 is a sectional view of the utility model embodiment.

Fig. 2 is a cross-sectional view of the pressure cage and the valve seat of the embodiment of the utility model.

Fig. 3 is a cross-sectional view of the valve core of the embodiment of the utility model.

FIG. 4 is an enlarged view of A in FIG. 1 .

Detailed ways

As shown in Figures 1-4, a pneumatic single-seat regulating valve includes a pneumatic diaphragm actuator 1, a bracket 2 and a valve body 3, and the pneumatic diaphragm actuator 1 is connected to the valve body 3 through a bracket 2. The valve body 3 includes a packing 31, a packing gland 32, a valve cover 33, a valve stem 34, a pressure cage 35, a valve core 36, a valve body 37, and a valve seat 38. The valve seat 38 is arranged in the valve body 37. The valve core 36 is sleeved in the pressure cage 35, the valve core 36 is connected to the valve stem 34, and the valve stem 34 is set with a valve cover 33, and the valve stem 34 passes through the valve cover 33 and performs The mechanism 1 is connected, the valve cover 33 and the valve stem 34 are sealed and connected with the packing 31 through the packing gland 32, and the valve core 36 moves up and down along the pressure cage 35 through the valve stem 34 to seal and break away from the valve seat 38 The contact surface between the valve seat 38 and the valve core 36 is provided with a stepped sealing surface 381 from wide to narrow, and each layer of sealing surface 381 is attached with a sealing gasket 382. The side of the pressure cage 35 The wall is provided with several throttling grooves 351 for the circulation of the medium in the valve body 37. The throttling grooves 351 are funnel-shaped, and the valve stem 34 is provided with a positioning ruler 341 indicating the flow rate of the fluid. A scale 21 corresponding to the positioning scale 341 is provided on the top, a ceramic protective layer is attached to the inner wall of the valve core 36, the valve core 36 is made of stainless steel, and a valve seat 38 and the valve body 37 are provided. There is a sealing gasket 382 .

During the use of the utility model, the medium first flows through the medium inlet on one side of the valve body 37, and its flow path is an S-shaped structure. When the regulating valve is not activated, the valve core 36 is in a closed state. When the seat 38 abuts against each other, the positioning scale 341 indicates the lowest scale of the scale 21, and the valve core 36 seals the valve seat 2. When in use, the valve stem 34 in the bracket 2 is driven by the pneumatic film actuator 1 to make the valve core 36 Move up and down in the pressure cage 35 and close the valve seat 38 to achieve opening and closing. In the open state, when the valve core 36 is at the highest position, the positioning scale 341 indicates the highest scale of the scale 21, and the valve core 36 is separated from the valve seat. The positioning scale 341 provided on the valve stem 34 shows the stroke of the valve stem 34, and then indicates the size of the fluid flow, so as to adjust the fluid flow in real time and improve the overall reliability. When one end of the valve stem 34 passes through the valve core 36, it passes through the nut and the valve The core 36 is fixedly connected, and the other end passes through the bonnet 33 to connect with the pneumatic film actuator 1. There is a gap between the bonnet 33 and the valve stem 34, and a filler 31 is added to the gap between the bonnet 33 and the valve stem 34. The filler 31 can It is PTFE V-shaped packing or PTFE asbestos, and then sealed with the packing gland 32, so that the valve stem 34 and the valve cover 33 are air-tight, so that the whole regulating valve is convenient to open and close, and the operation is simple. The seat 38 is provided with three layers of stepped sealing surfaces 381 from wide to low, and the sealing gasket 382 is fixedly fastened on each layer of sealing surface 381, so that the valve core 36 is worn during the corrosion process during use, but due to The setting of the three-layer sealing surface 381 makes the circular valve core 36 seal according to the sealing surface 381 that can enter the next layer after wear and tear, which improves the sealing performance of the regulating valve. The throttling groove 351 for medium circulation in the valve body 38 makes the opening and closing of the regulating valve easier, and the throttling groove 351 adopts a funnel-shaped structure, so that when the medium is opened from the valve core 36, part of the medium will flow from the bottom of the throttling groove 351. When the small hole enters the large hole, the medium is sprayed in with the throttling groove 351, and the medium collides with each other at the center of the pressure cage 35. During the collision, the energy is consumed, which acts as a buffer and reduces the flow rate while ensuring a high flow rate. The possibility of vortex formation is eliminated, thereby greatly reducing the noise generated by the medium, improving the anti-cavitation and anti-flash performance, and increasing the service life of the valve.

Claims (5)

1. A pneumatic single-seat control valve, comprising a pneumatic diaphragm actuator, a bracket and a valve body, the pneumatic diaphragm actuator is connected to the valve body through a bracket, it is characterized in that: the valve body includes a filler, a packing gland , valve cover, valve stem, pressure cage, valve core, valve body, valve seat, the valve seat is set in the valve body, the valve core is sleeved in the pressure cage, the valve core is connected to the valve stem, the The valve stem is covered with a bonnet, and the valve stem passes through the bonnet to connect with the pneumatic film actuator. Moving up and down along the pressure cage to seal and break away from the valve seat, the contact surface between the valve seat and the valve core is provided with a stepped sealing surface from wide to narrow, and a sealing gasket is attached to each layer of the sealing surface. 2. A pneumatic single-seat control valve according to claim 1, characterized in that: the side wall of the pressure cage is provided with several throttling grooves for the circulation of the medium in the valve body, and the throttling grooves are funnel-shaped . 3. A pneumatic single-seat regulating valve according to claim 2, characterized in that: the valve stem is provided with a positioning scale indicating the fluid flow rate, and the bracket is provided with a scale corresponding to the positioning scale ruler. 4. A pneumatic single-seat control valve according to claim 3, characterized in that a ceramic protective layer is attached to the inner wall of the valve core, and the valve core is made of stainless steel. 5. A pneumatic single-seat control valve according to claim 4, characterized in that: a sealing gasket is provided between the valve seat and the valve body.