CN206175721U - Be applied to switching -over valve of secret fluid sampling process - Google Patents

Abstract

The utility model provides a reversing valve used in the underground fluid sampling process, comprising: a valve body top cover, a valve body, a valve core, a spring and a valve body bottom cover. In the middle of the top cover of the valve body, there is a valve body inlet connected to a high-pressure air source. In the middle of the valve body, there are valve body liquid inlet and valve body liquid outlet. The straight through hole is equipped with a spring at the lower part of the valve core and the protrusion inside the bottom cover of the valve body. In the natural state, the liquid inlet of the valve body, the through hole of the valve core and the liquid outlet of the valve body are connected, and the external environment fluid flows in naturally. When the high-pressure gas enters the L-shaped through hole through the air inlet of the valve body, it pushes the valve core to move downward, and finally the gas outlet of the L-shaped through hole of the valve core is connected with the liquid outlet of the valve body, and the external fluid cannot flow in. According to the reversing valve of the utility model, the gas channel and the liquid channel are separated, and the liquid channel is in a normally open state, and the sampling liquid can freely flow into the sampling device without pressure sensitive elements and starting pressure.

Description

A reversing valve used in underground fluid sampling process

technical field

The utility model relates to the technical field of instrument valve control, in particular to a reversing valve used in an underground fluid sampling process.

Background technique

In the field of underground environmental pollution monitoring and control, it is necessary to collect underground fluid at a certain depth for testing and analysis. At the same time, groundwater sampling and monitoring are required in hydrogeological surveys, monitoring of underground storage of garbage, and geological storage of CO ₂ . However, the existing domestic monitoring technology cannot fully meet the needs. Among them, the gas-driven U-shaped tube sampler is one of the most effective sampling devices, but due to its core component—one-way valve or similar functional components The performance is unstable, and it is easy to be blocked by sand and cause component failure. Once such components fail, it means that the entire sampling layer is scrapped, which not only causes economic losses, but also completely loses the sampling function of the sampling well. Therefore, the one-way valve is of great significance to the traditional U-shaped tube sampler.

The existing directional control elements used in the underground fluid sampling process are mainly check valves. The main type is a spring check valve, the check valve spool is usually a rubber disc, and the spring is used to close the liquid inlet of the valve body by the valve disc. When the liquid has a certain pressure from the liquid inlet exceeding the spring force, the one-way valve conducts. When the fluid flows in from the liquid outlet, the one-way valve does not conduct because the valve clack closes the liquid inlet of the valve body. However, when the reverse pressure exceeds the sealing pressure of the spool when the reverse pressure is too large, the one-way valve is destroyed and the one-way conduction function becomes invalid. Therefore, this type of check valve has strict requirements on the pressure of the working environment. There is a starting pressure in the forward direction and a maximum sealing pressure in the reverse direction. In addition, there are gravity unidirectional control elements, "a multi-stage monitoring well pneumatic pump sampling system device and its method" (publication number: CN 102749223 A) and "a U-shaped tube sampler downhole pipeline connection device" (published No.: CN 203798628U) has announced the structure of a kind of gravity compound check valve. Similar to the spring-type one-way valve, it is a normally closed structure with a starting pressure, and only when the liquid pressure exceeds the starting pressure, can one-way conduction be realized. In addition to pressure requirements, these check valves are also sensitive to impurities in the fluid environment. When particles and impurities accumulate at the position where the liquid inlet contacts the valve core, the one-way conduction function of the check valve will also fail. These shortcomings of the check valve limit its application depth. In addition, many check valves are sealed with sealing rings or combined sealing with thread + raw tape, and there are problems such as material aging, corrosion and failure in various use environments. Once the seal fails, it will lead to the failure of the entire sampling system.

Utility model content

In view of the above problems, in order to solve the defects of unstable service life and easy blockage and failure of the one-way valve, the traditional one-way conduction idea is expanded to the idea of direction control. The purpose of this utility model is to provide a kind of The reversing valve, the structure design of the device is ingenious and novel, the gas channel and the liquid channel are separated, and the liquid channel is in the normally open state, the sampling liquid can freely flow into the sampling device, there is no pressure sensitive element, no starting pressure, and it can withstand high pressure Pressure, low requirements on the liquid environment of the application, has good application value.

In order to achieve the above object, a reversing valve used in the underground fluid sampling process of the present utility model is characterized in that it includes: a valve body top cover, a valve body, a valve core, a spring and a valve body bottom cover.

The top cover of the valve body is provided with a valve body air inlet connected to a high-pressure air source in the middle.

The valve body is a cylindrical structure, and the valve body liquid inlet and the valve body liquid outlet are symmetrically opened on the two side walls near the middle position, and the upper part of the inner wall of the valve body is from the top to the valve body The position of the liquid inlet and the liquid outlet of the valve body is an inner wedge-shaped ring surface.

The spool has a stepped cylindrical shape as a whole, the lower part is thinner and the upper part is thicker, an L-shaped through hole is opened at the top of the spool, and a horizontal through hole is opened in the middle of the spool, and the L-shaped through hole exits The air port and the straight-through hole are in the same plane, and the upper half of the outer side of the valve core is an outer wedge-shaped annular surface, which cooperates with the inner wedge-shaped annular surface of the valve inner cavity to form a wedge-shaped self-sealing structure. The lower end of the core is a thin cylinder.

The bottom cover of the valve body is connected with the valve body, and a protrusion is provided on the inside and outside of the valve body, and a through hole is provided in the middle, and a spring is arranged between the lower part of the valve core and the inside protrusion of the bottom cover of the valve body. .

The top cover of the valve body is a flange-shaped structure, and a groove smaller than the diameter of the inner cavity of the valve body is provided on the surface connected to the valve body, and the depth of the groove is 1-2mm.

The bottom end of the thin cylinder at the lower end of the valve core is formed into an arc-shaped structure,

The end surface of the protruding through hole inside the bottom cover of the valve body is formed in an arc shape, and when the valve core is at the bottom position, the end surface engages with the bottom end of the thin cylinder at the lower end of the valve core.

The diameter of the through hole in the protrusion outside the bottom cover of the valve body is formed to be larger than the diameter of the through hole inside the bottom cover of the valve body, and a floating ball is placed in the through hole outside the bottom cover of the valve body. The outer through hole of the bottom cover of the valve body below the ball is also provided with a pressure relief adapter joint, which is a cylindrical hollow cylinder structure, and the end surface of the contact end with the floating ball is provided with a convex The outer wall of the cylinder at this end is smooth, and is fitted with an interference fit with the outer through hole of the bottom cover of the valve body; the other end of the pressure relief adapter is connected to one end of the pressure regulating conduit, and the pressure regulating conduit The other end is connected with the pressure regulating hole provided at the liquid outlet of the valve body.

The wedge-shaped slope of the inner wedge-shaped annulus formed on the upper part of the inner cavity wall of the valve body and the outer wedge-shaped annulus corresponding to the inner wedge-shaped annulus formed on the upper half of the valve core is 2-5°.

The material of the spring can be metal or non-metal according to the requirements of groundwater sampling and analysis.

The air inlet of the valve body on the top cover of the valve body has a diameter of 3-5mm.

A reversing valve used in the underground fluid sampling process of the utility model comprises: a valve body top cover, a valve body, a valve core, a spring and a valve body bottom cover.

The reversing valve is a cylindrical structure with a diameter of 8-20 mm and a height of 20-40 mm. The valve body top cover, valve body bottom cover and the valve body are welded or threaded to form a whole.

The top cover of the valve body is a flange-shaped structure, and a valve body air inlet (3-5 mm in diameter) is opened in the middle, which is connected with a high-pressure air source. The surface connected to the valve body is provided with a groove smaller than the diameter of the inner cavity of the valve (groove depth 1-2mm),

The two side walls of the valve body near the middle position are symmetrically provided with a valve body liquid inlet and a valve body liquid outlet. Connected, the upper part of the inner wall of the valve body is designed as an inner wedge-shaped ring surface from the top to the position close to the valve body liquid inlet and valve body liquid outlet, and the wedge-shaped slope is 2-5°.

The spool is in the shape of a stepped cylinder as a whole, and its lower part is thinner and its upper part is thicker. The top of the spool is provided with a spool air outlet of an L-shaped through hole, and the middle of the spool is provided with a horizontal through hole, and the spool air outlet of the L-shaped through hole and the through hole are in the same plane. The outside of the cylinder above the through-hole of the spool (that is, the upper part of the spool) is designed as an outer wedge-shaped annulus, which corresponds to the wedge-shaped annulus of the inner cavity of the valve. As the spool moves downward, the two wedge-shaped annuli interact contact, when the valve core is at the bottom position, the outer wedge-shaped structure forms a wedge-shaped self-sealing structure with the inner wedge-shaped inner cavity wall on the upper part of the valve body, so as to play a sealing role. The lower end of the spool is a thin cylinder, and the bottom end of the cylinder is designed as an arc-shaped structure.

The inside and outside of the bottom cover of the valve body are respectively provided with a protrusion and a through hole in the middle. The end face of the through hole on the inside of the bottom cover of the valve body is an arc shape. end engagement.

A spring is arranged at the lower part of the valve core and the inside protrusion of the bottom cover of the valve body, and the spring keeps the valve core always on the upper part of the inner cavity of the valve body under normal conditions. The thin cylinder at the lower end of the spool and the protrusion inside the bottom cover of the valve body provide the attachment position for the spring, and at the same time, both ends of the spring are fixed to prevent the spool from rotating.

The diameter of the through hole in the protrusion outside the bottom cover of the valve body is formed to be larger than the diameter of the through hole (i.e. the pressure relief hole of the bottom cover) inside the bottom cover of the valve body, and a plastic floating ball is placed in the through hole outside the bottom cover of the valve body. There is also a pressure relief adapter in the outer through hole of the bottom cover of the valve body below the floating ball. The end face of the ball contact end is provided with a protrusion, which can ensure that there is always a gap between the floating ball and the end face of the pressure relief adapter, so that the float cannot seal the pressure relief adapter and keep the pressure relief channel unblocked. The outer wall of the cylinder is smooth, and it is assembled with the outer through hole of the valve body bottom cover; the other end of the pressure relief adapter is connected with the end of the pressure regulating conduit by expansion or welding, and multiple rings can be arranged on the outer wall. Raised to increase the sealing effect between the joints when the expansion joint is used. The other end of the pressure regulating conduit is connected with a pressure regulating hole arranged at the liquid outlet of the valve body.

When the reversing valve is in the natural state of the spring, the through hole of the valve core is connected with the liquid inlet of the valve body and the liquid outlet of the valve body to form a passage, and the external environment fluid flows naturally. When the high-pressure gas enters the L-shaped through hole through the valve body inlet, the valve core is pushed down, and finally the gas outlet of the L-shaped through hole of the valve core is connected with the valve body liquid outlet, and external fluid cannot flow in. Because the two ends of the spring are fixed, it can ensure that the corresponding relationship between the valve body and the holes of the valve core remains unchanged. The liquid outlet of the valve body is a three-way structure, and one of the small holes is the pressure regulating hole, which is expanded and tightly connected with the pressure relief adapter through the pressure regulating conduit.

When the reversing valve is in normal use, it is in a liquid environment, in which the air inlet of the valve body is connected to the high-pressure gas source, and is not directly connected to the liquid environment. The liquid inlet hole of the valve body and the through hole of the valve core are directly connected to the liquid environment. , the liquid outlet of the valve body is directly communicated with the fluid storage container of the sampling device. When the air inlet of the valve body is not connected with the high-pressure gas source, the valve core is at the upper position of the valve body under the action of the spring. At this time, the valve body liquid outlet, the valve core through hole and the valve body liquid inlet form a passage, and the external environment fluid flows into the flow storage container through the valve body liquid inlet, the valve core through hole and the valve body liquid outlet. When the air inlet of the valve body is connected to the high-pressure gas source, the high-pressure gas enters the free space between the inner cavity of the valve body and the end surface of the valve core through the air inlet of the valve body, and the pressure increases rapidly. When the pressure on the end face of the spool is greater than the pressure applied to the spool by the spring, the spool moves downward, and the gap between the wedge-shaped ring surface at the upper end of the spool and the wedge-shaped ring surface of the inner cavity of the spool becomes smaller and smaller. Form a self-sealing effect. As the spool moves down, the space between the lower part of the spool and the inner cavity of the valve body gradually decreases, and the fluid therein flows out of the valve body through the through hole in the bottom cover of the valve body. When the spool reaches the lowest position, the lower end of the L-shaped through hole of the spool communicates with the liquid outlet hole of the valve body, and the two wedge-shaped annular surfaces form a wedge-shaped self-sealing structure, thereby playing a sealing role. At this moment, the air inlet of the valve body is connected with the liquid outlet of the valve body through the L-shaped hole of the valve core, and the liquid outlet of the valve body is not connected with the liquid inlet of the valve body. When the pressure of the air inlet of the valve body is reduced until the connection with the high-pressure gas source is closed, the pressure of the spring on the spool is gradually greater than the pressure of the high-pressure gas on the spool, and the spring pushes the spool to move upward. The L-shaped through hole of the valve core is staggered with the liquid outlet of the valve body, the air inlet of the valve body is not connected with the liquid outlet of the valve body, and the liquid outlet of the valve body is connected with the liquid inlet of the valve body again through the through hole of the valve core.

technical effect

According to the reversing valve of the utility model, the gas channel and the liquid channel are separated at the liquid sampling port, that is, the liquid outlet of the valve body, and the liquid channel is in a normally open state, so that underground fluid can freely flow into the sampling device. The starting pressure is 0, and no pressure-sensitive parts are exposed, so it can be applied to sampling environments of various depths.

In addition, under normal conditions, the sampling channel of the reversing valve of the present invention is in a normally open state, and the gas flow channel is in a normally closed state. The structural design improves the ability to resist the risk of sediment blockage, innovatively uses the high-pressure gas during sampling as the power source to realize the switching or opening and closing of the channel, which is well adapted to the extreme environment of long-term underground monitoring; compared with the one-way valve, there is no start-up pressure, it is still applicable in places where the water head difference is small near the groundwater level; the pneumatic pressure can be adjusted in a large range, and there is no pressure sensitive part, so that this part can also be applied in deep formation sampling; the sealing structure adopts a sliding wedge-shaped annulus The self-sealing structure eliminates the sealing form that is prone to failure, and the sealing effect is better and the application range is wider.

Description of drawings

Fig. 1 is a schematic diagram of the structure of a reversing valve used in an underground fluid sampling process according to an embodiment of the present invention;

Figure 2 is a cross-sectional view of the reversing valve in a natural state; Figure 2-1 is a partial enlarged view of Figure 2;

Fig. 3 is a cross-sectional view of the reversing valve in working state; Fig. 3-1 is a partially enlarged view of Fig. 3 .

reference sign

1-Valve body air inlet, 2-Valve body top cover, 3-Valve body, 4-Spool, 5-Valve body liquid inlet, 6-Spring, 7-Valve body bottom cover, 8-Floating ball, 9 -Pressure relief adapter, 10-spool L-shaped through-hole air inlet, 11-spool L-shaped through-hole air outlet, 12-valve body liquid outlet, 13-pressure regulating hole, 14-pressure regulating conduit, 15-bottom cover pressure relief hole, 16-spool through hole.

detailed description

Hereinafter, a reversing valve used in the underground fluid sampling process of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a reversing valve used in the underground fluid sampling process according to an embodiment of the present invention. As shown in Figure 1 , the reversing valve of the present utility model has: a valve body top cover 2, a valve body 3, a valve core 4, a spring 6, a valve body bottom cover 7, a floating ball 8 and a pressure regulating conduit 14.

The reversing valve is a cylindrical structure with a diameter of 8-20mm and a height of 20-40mm. The valve body top cover 2, valve body bottom cover 7 and valve body 3 are welded or threaded to form a whole. The material of each component of the reversing valve can be selected to use metallic materials or inorganic non-metallic materials according to specific sampling and analysis requirements.

The valve body top cover 2 is a flange-like structure with a valve body air inlet 1 (with an inner diameter of 3-5 mm, usually 3 mm) in the middle, which is connected to a high-pressure gas source. On the surface connected to the valve body 3, there is a groove smaller than the diameter of the inner cavity of the valve body 3 (the depth of the groove is 1 ~ 2mm). The function of the groove is to increase the free area of the high-pressure gas acting on the top of the valve core to increase The thrust that pushes the spool.

The valve body liquid inlet 5 and the valve body liquid outlet 12 are symmetrically opened on both side walls of the valve body 3 near the middle position, the valve body liquid inlet hole 5 is directly connected to the external fluid environment, and the valve body liquid outlet hole 12 is connected with the sampling device The upper part of the inner wall of the valve body 3 is designed as an inner wedge-shaped ring surface from the top to the position close to the valve body liquid inlet 5 and the valve body liquid outlet 12, and the wedge-shaped slope is 2-5° .

The spool 4 is in the shape of a stepped cylinder as a whole, and its lower part is thinner and its upper part is thicker. The top of the spool is provided with a spool air inlet 10 with an L-shaped through hole, and the middle of the spool is provided with a horizontal through hole 16, and the L-shaped through hole air outlet 11 of the spool is in the same plane as the through hole 16 of the spool. The outer side of the cylinder (i.e. the upper part of the spool) above the through hole 16 of the spool is formed as an outer wedge-shaped annulus, which corresponds to the wedge-shaped annulus of the inner cavity of the valve body 3. As the spool 4 moves downward, the two wedges The ring surfaces are in contact with each other. When the valve core 4 is at the bottom position, its outer wedge-shaped structure forms a wedge-shaped self-sealing structure with the inner wedge-shaped inner cavity wall on the upper part of the valve body 3, so as to play a sealing role. The lower end of the spool 4 is a thin cylinder, and the bottom end of the cylinder is designed as an arc-shaped structure.

The inside and outside of the valve body bottom cover 7 are respectively provided with a protrusion and a through hole in the middle. The bottom end of the thin cylinder engages.

A spring 6 is installed at the lower part of the valve core 4 and the inside protrusion of the valve body bottom cover 7, and the spring 6 keeps the valve core 4 always on the top of the inner chamber of the valve body 3 under normal conditions. The thin cylinder at the lower end of the valve core 4 and the inner protrusion of the valve body bottom cover 7 provide attachment positions for the spring 6, and the two ends of the spring 6 are fixed to prevent the valve core 4 from rotating.

The diameter of the through hole in the protrusion on the outside of the valve body bottom cover 7 is formed to be greater than the diameter of the through hole (i.e. the bottom cover pressure relief hole 15) inside the valve body bottom cover 7, and a plastic material is placed in the outside through hole of the valve body bottom cover 7. The float 8 is also provided with a pressure relief adapter 9 in the outer through hole of the valve body bottom cover 7 below the float 8, and the pressure relief adapter 9 is a cylindrical hollow cylinder structure (the inner diameter of the middle through hole is 1~3mm), the end surface of the contact end of the floating ball 8 is provided with a protrusion, which can ensure that there is always a gap between the floating ball 8 and the end surface of the pressure relief adapter 9, so that the floating ball 8 cannot seal the pressure relief rotor The outer wall of the cylinder at this end is smooth, and it is fitted with the outer through hole of the valve body bottom cover 7 in an interference fit; the other end of the pressure relief adapter 9 and one end of the pressure regulating conduit 14 pass through the expansion joint 9. If it is connected by means of tightness or welding, multiple ring-shaped protrusions can be provided on the outer wall to increase the sealing effect between the joints when the expansion-tight connection is used. The other end of the pressure-regulating conduit 14 is in expansion-tight connection with the pressure-regulating hole 13 arranged at the liquid outlet 12 of the valve body.

Fig. 2 is a cross-sectional view of a reversing valve in a natural state according to an embodiment of the present invention. As shown in Figure 2, under the natural state of the spring, the valve body liquid inlet 5, the valve core through hole 16 and the valve body liquid outlet 12 are connected to form a passage, and the sampling channel is normally open. state, the gas flow channel is in a normally closed state, and the external environment fluid flows into the flow storage container through the valve body liquid inlet 5, the valve core through hole 16 and the valve body liquid outlet 12.

Fig. 3 is a cross-sectional view of the reversing valve in an embodiment of the present invention in a working state. As shown in Figure 3, in the natural state, high-pressure gas gathers near the inner groove of the valve body top cover 2 through the valve body inlet 1, and the pressure continues to increase. When the high-pressure gas acts on the top surface of the valve core 4 greater than the spring 6 The elastic force pushes the spool 4 to move downward, and the spring 6 is compressed. The liquid in the inner cavity of the valve body 3 is squeezed, and flows to the float 8 along the middle through hole of the bottom cover 7 of the valve body (that is, the pressure relief hole 15 of the bottom cover), and pushes the float 8 to the top of the pressure relief adapter 9 , due to the protrusion of the top surface of the pressure relief adapter 9, the pressurized groundwater flows into the pressure regulating conduit 14, and then enters the liquid outlet 12 of the valve body. When the valve core 4 is pushed to the lowest position, the L-shaped through-hole air outlet 11 of the valve core is connected to the liquid outlet 12 of the valve body, and the high-pressure gas enters the liquid outlet 12 of the valve body. At this time, the pressure at the pressure regulating hole 13 Higher than the pressure of the pressurized liquid at the spring 6, so the floating ball 8 floats up to block the through hole of the valve body bottom cover 7 (ie the bottom cover pressure relief hole 15). High-pressure gas can only flow along the direction of valve body inlet 1 → valve core L-shaped through hole air inlet 10 → valve core L-shaped through hole gas outlet 11 → valve body liquid outlet 12.

When the high-pressure gas source is turned off, the pressure of the high-pressure gas in the inner groove of the top cover 2 of the valve body drops, and the pressure of the spring 6 in the inner cavity of the valve body 3 is greater than the gas pressure, so the elastic force of the spring 6 moves the valve core 4 upward, and the floating ball 8 does not move up. Under the action of high-pressure gas again, the reversing valve returns to its natural state.

The material of the spring 6 can be metal or non-metal according to the requirements of groundwater sampling and analysis. Because the two ends of the spring 6 are fixed, it can ensure that the corresponding relationship between the holes of the valve body 3 and the valve core 4 remains unchanged. The liquid outlet 12 of the valve body is a three-way structure, and the small hole in it, the pressure regulating hole 13 , is connected to the pressure relief adapter 9 through the pressure regulating conduit 14 . It should be noted that most of the embodiments of the present utility model adopt expansion-tight connection, and of course other connection methods such as welding and screw connection can also be used according to actual needs.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model rather than limit them. Although the present utility model has been described in detail with reference to the embodiments, those skilled in the art should understand that any modification or equivalent replacement of the technical solution of the present utility model does not depart from the spirit and scope of the technical solution of the present utility model, and all of them should cover Within the scope of the claims of the present invention.

Claims (7)

1. a kind of reversal valve for being applied to sampling underground fluid process, it is characterised in that including：Valve body top cover, valve body, valve element, Spring and valve body bottom,

The valve body top cover, centre offers the valve body air inlet being connected with high-pressure air source；

The valve body, is cylindrical structure, and valve body inlet and valve are symmetrically offered in the two side near intermediate position Body liquid outlet, the body cavity wall top is near the position of the valve body inlet and the valve body liquid outlet from top Interior wedge-shaped anchor ring；

The valve element, overall cylindric in step, its underpart is thinner, and top is thicker, and the valve element top offers L-type through hole, Horizontal clear opening is offered in the middle of the valve element, the L-type through hole gas outlet and clear opening in approximately the same plane, the valve element The first half in outside cooperatively forms wedge shape from close in the anchor ring of outer wedge structure with the described interior wedge-shaped anchor ring of the body cavity Envelope construction, the valve element lower end is thin cylinder；

The valve body bottom, is connected with the valve body, and its inner side and outer side is respectively provided with raised a, intermediate throughholes, in the valve element Spring is installed between bottom and the valve body bottom inner bulge.

2. the reversal valve of sampling underground fluid process is applied to as claimed in claim 1, it is characterised in that

The valve body top cover is flange-like configuration, is provided with less than the body cavity diameter in itself and the face that the valve body is connected Groove, the groove depth of the groove is 1~2mm.

3. the reversal valve of sampling underground fluid process is applied to as claimed in claim 1, it is characterised in that

The thin cylinder bottom of the valve element lower end is formed as arc structure,

The valve body bottom inner bulge through hole end face is formed as arcuation, when the valve element be located at bottom position when, the end face with The thin cylinder bottom engagement of the valve element lower end.

4. the reversal valve of sampling underground fluid process is applied to as claimed in claim 1, it is characterised in that

Through-hole diameter in the projection of the valve body bottom outside is formed larger than the through-hole diameter on the inside of the valve body bottom, in institute State in the outer side through hole of valve body bottom and be placed with ball float, also set in the outer side through hole of the valve body bottom below the ball float Pressure release adapter coupling is equipped with, the pressure release adapter coupling is columned hollow cylinder structure, its end with the ball float contact jaw Face is provided with projection, and the cylindrical body outer wall at the end is smooth, the outer side through hole elastic conjunction with the valve body bottom；The pressure release switching The other end of joint is connected with one end of pressure regulation conduit, the other end of the pressure regulation conduit be arranged at the valve body liquid outlet Regulator hole connection.

5. the reversal valve for being applied to sampling underground fluid process as described in Claims 1 to 4 any one, it is characterised in that

It is formed at the interior wedge-shaped anchor ring on the body cavity wall top and is accordingly formed at institute with the interior wedge-shaped anchor ring The wedge-shaped gradient for stating the outer wedge-shaped anchor ring of the valve element first half is 2~5 °.

6. the reversal valve for being applied to sampling underground fluid process as described in Claims 1 to 4 any one, it is characterised in that

The requirement of water sampling analysis can use metal material or non-metallic material under the material base area of the spring.

7. the reversal valve for being applied to sampling underground fluid process as described in Claims 1 to 4 any one, it is characterised in that

The valve body air inlet of the valve body top cover is 3~5mm of diameter.