CN210461708U

CN210461708U - Stop valve

Info

Publication number: CN210461708U
Application number: CN201921484308.2U
Authority: CN
Inventors: 曹广滨; 李垚; 张钊; 涂翔; 陆江南
Original assignee: Rego Fluid Technology Shanghai Co ltd
Current assignee: Rego Fluid Technology Shanghai Co ltd
Priority date: 2019-09-04
Filing date: 2019-09-04
Publication date: 2020-05-05
Anticipated expiration: 2029-09-04

Abstract

The utility model provides a stop valve, which comprises a valve cover, a valve rod and a valve core, wherein the valve core is connected with the end part of the valve rod, the valve cover is sleeved on the valve rod, the stop valve also comprises a first sealing element and an elastic element, the first sealing element is positioned in the valve cover, the first sealing element is sleeved on the valve rod, the outer peripheral surface of the valve rod is provided with a section of conical surface, the diameter of the conical surface is gradually reduced along the direction away from the valve core, and the first sealing element is in sealing fit with the conical surface; the elastic piece sets up on the valve rod, and the elastic piece exerts the elastic force of the direction of keeping away from the case to the valve rod all the time. According to the stop valve, only the first sealing element is arranged between the valve rod and the valve cover, leakage points can be reduced through single-layer sealing, and the sealing effect is guaranteed; through the effort of elastic component to the valve rod, make the valve rod compress tightly first sealing member all the time, guaranteed the sealed effect between valve rod and the valve gap, especially under low temperature state, the deformation that first sealing member takes place because of the low temperature can be compensated to the effort of elastic component.

Description

Stop valve

Technical Field

The utility model relates to a stop valve.

Background

The conventional stop valve usually adopts a multi-layer packing mode for sealing between the valve rod and the valve cover, and achieves the sealing effect through the transverse deformation generated by the stress of the packing. However, this method has many leakage points (between the packing and the packing, between the packing and the bonnet, etc.) due to the multi-layer packing, and the contact surface between the packing and the valve rod is large, so that the good sealing effect cannot be achieved durably and effectively.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a stop valve to solve the poor problem of conventional stop valve seal effect.

In order to solve the above problem, the utility model provides a following technical scheme:

the utility model provides a stop valve, including valve gap, valve rod and case, the case with the end connection of valve rod, the valve gap cover is in on the valve rod, stop valve still includes:

the first sealing element is positioned in the valve cover, the first sealing element is sleeved on the valve rod, the outer peripheral surface of the valve rod is provided with a section of conical surface, the diameter of the conical surface is gradually reduced along the direction far away from the valve core, and the first sealing element is in sealing fit with the conical surface;

the elastic piece is arranged on the valve rod and always applies elastic force to the valve rod in the direction away from the valve core.

In this technical scheme, through the effort of elastic component to the valve rod, make the valve rod compress tightly first sealing member all the time, guaranteed the sealed effect between valve rod and the valve gap.

Preferably, the stop valve further comprises a guide sleeve, the guide sleeve is sleeved on the valve rod and fixed in the valve cover, and the first sealing element is clamped between the end face of the guide sleeve and the inner end face of the valve cover.

In this technical scheme, through setting up the uide bushing, press from both sides first sealing member with the valve gap together tightly, guaranteed the positional stability of first sealing member.

Preferably, the inner peripheral surface of the guide sleeve is provided with a limit flange protruding towards the direction of the valve rod, an inverted conical space is formed between the inner peripheral surface of the limit flange and the conical surface of the valve rod, the first sealing element is provided with an extension part extending to the inverted conical space, and the extension part is in sealing fit with the inner peripheral surface of the limit flange and the conical surface of the valve rod.

In this technical scheme, can extend to the extension in the back taper space through the setting, when making the axiality between valve rod and the first sealing member when the deviation appears, the extension can receive the extrusion, can effectively improve and reveal the problem.

Preferably, the outer peripheral surface of the valve rod is provided with a section of first guide surface, the first guide surface is located between the conical surface and the valve core, the inner peripheral surface of the guide sleeve is provided with a section of second guide surface, the first guide surface is matched with the second guide surface, the first guide surface and the second guide surface are coaxially arranged, and the cross section of the second guide surface is circular.

In this technical scheme, the uide bushing has guaranteed the accuracy of valve rod along axial removal, and the uide bushing does not restrict the rotation of valve rod.

Preferably, the outer peripheral surface of the valve core is in threaded fit with the inner peripheral surface of the valve cover, the valve rod is connected with the valve core, and the valve rod drives the valve core to rotate around the axis.

In the technical scheme, the valve rod drives the valve core to rotate, so that the valve core moves up and down relative to the valve cover, the valve core is enabled to close or open the valve port, and the stop valve is opened and closed.

Preferably, an insertion hole is formed in one end of the valve core facing the valve rod, the valve rod is inserted into the insertion hole of the valve core, the outer peripheral surface of the valve rod is provided with a matching surface matched with the inner peripheral surface of the insertion hole, the cross section of the insertion hole is non-circular, and the insertion hole is arranged coaxially with the valve rod.

In the technical scheme, the valve rod can drive the valve core to rotate, but the relative movement between the valve rod and the valve core along the axial direction is not limited.

Preferably, a mounting hole is formed in one end, facing the valve core, of the valve rod, the elastic piece is a compression spring, the compression spring is placed in the mounting hole of the valve rod, and two ends of the compression spring are respectively abutted to the bottom surface of the insertion hole and the bottom surface of the mounting hole.

In the technical scheme, the compression spring always applies a pressing force to the valve rod in the above mode, so that the valve rod always presses the first sealing element, and the sealing effect between the valve rod and the valve cover is ensured.

Preferably, the stop valve still includes the hand wheel, the hand wheel is installed the valve rod is located the tip outside the valve gap, the hand wheel with the valve rod is for dismantling the connection.

In this technical scheme, can design between hand wheel and the valve rod and be connected for dismantling, the hand wheel can independently be dismantled and change for the handle use, can not influence original sealed effect, can satisfy and use under the many occasions condition.

Preferably, the shut-off valve further comprises:

the hand wheel is mounted at the end part of the valve rod, which is positioned outside the valve cover, the elastic part is a compression spring, and the hand wheel is provided with an accommodating cavity for accommodating the compression spring;

the limiting ring, the limiting ring with the valve rod is located the outer end fixing of valve gap, the limiting ring lid is in hold on the opening in chamber, compression spring's both ends respectively with hold the bottom surface in chamber, the limiting ring contacts.

In this technical scheme, compression spring installs in the hand wheel, and compression spring's compression state remains the invariant throughout, can provide continuous stable thrust, and, external compression spring does not need special material, can reduce the cost.

Preferably, the shut-off valve further comprises:

the valve body is provided with a valve port, and the valve port is arranged between an inlet and an outlet of the valve body;

and the second sealing element is fixed on the end face, facing the valve port, of the valve core, and can be in sealing fit with the valve port.

In this technical scheme, through setting up the second sealing member, when having guaranteed that the stop valve is closed, the sealed effect between second sealing member and the valve port.

Preferably, the stop valve further comprises a fixing member, the fixing member is fixed to the valve core, and the fixing member clamps the second sealing member to the valve core.

In this technical scheme, increase the mounting, can prevent that the second sealing member from droing, when the area of we increase the second sealing member, the condition that also can not appear droing, we just so can increase the flow area of valve.

Preferably, the stop valve further comprises a valve body, an outer peripheral surface of the valve cover is matched with an inner peripheral surface of the valve body, the outer peripheral surface of the valve cover is provided with a first radial surface protruding outwards in the radial direction, the inner peripheral surface of the valve body is provided with a second radial surface protruding inwards in the radial direction, the second radial surface is provided with a protruding area protruding towards the first radial surface, the protruding area is in sealing fit with the first radial surface, and a part of the protruding area, which is in contact with the first radial surface, forms an annular shape.

In this technical scheme, adopt the metal to seal with the metal contact's is sealed firmly, the leak point just has one, designs the protruding region of salient form simultaneously on the second radial face of valve body, has reduced the area of contact between second radial face and the first radial face, and when the installation moment of torsion is the same, pressure obtains very big increase, is favorable to strengthening sealed effect.

Preferably, a valve rod mounting hole is formed in the valve cover, and the valve rod penetrates through the valve rod mounting hole; the stop valve still includes the dust ring, the dust ring set up in the valve rod with between the valve rod mounting hole.

In this technical scheme, the dust ring can prevent inside entering stop valve such as outside dust, tiny particle and water.

On the basis of the common knowledge in the field, the above preferred conditions can be combined at will to obtain the preferred embodiments of the present invention.

The utility model discloses an actively advance the effect and lie in:

according to the stop valve, only the first sealing element is arranged between the valve rod and the valve cover, leakage points can be reduced through single-layer sealing, and the sealing effect is guaranteed; through the effort of elastic component to the valve rod, make the valve rod compress tightly first sealing member all the time, guaranteed the sealed effect between valve rod and the valve gap, especially under low temperature state, the deformation that first sealing member takes place because of the low temperature can be compensated to the effort of elastic component.

Drawings

Fig. 1 is a schematic structural diagram of a first embodiment of the stop valve of the present invention.

Fig. 2 is a schematic cross-sectional view of the shut-off valve shown in fig. 1.

Fig. 3 is a partially enlarged view of the shut-off valve shown in fig. 2.

Fig. 4 is a partially enlarged view of the shut-off valve shown in fig. 2.

Fig. 5 is a schematic structural diagram of a second embodiment of the stop valve of the present invention.

Fig. 6 is a schematic cross-sectional view of the shut-off valve shown in fig. 5.

Description of the reference numerals

The valve cover 1, the bulge 11, the valve rod mounting hole 12 and the first radial surface 13; the valve rod 2, the conical surface 21, the first guide surface 22, the matching surface 23 and the mounting hole 24; a valve body 3 inserted into the hole 31; valve body 4, valve port 41, inlet 42, outlet 43, second radial surface 44, raised area 45; first seal 5, extension 51; the elastic member 6, the compression spring 61; the guide sleeve 7, the limiting flange 71 and the second guide surface 72; a hand wheel 8 accommodating the cavity 81; the dust-proof structure comprises an inverted cone-shaped space 9, a dust ring 10, a second sealing element 20, a limiting ring 30 and a fixing element 40.

Detailed Description

The present invention will be further described with reference to the following embodiments and drawings, and more details will be set forth in the following description in order to provide a thorough understanding of the present invention, but it is obvious that the present invention can be implemented in various other ways different from those described herein, and those skilled in the art can make similar generalizations and deductions according to the actual application without departing from the spirit of the present invention, and therefore, the scope of the present invention should not be limited by the contents of the embodiments.

Example one

As shown in fig. 1 to 4, it is a first embodiment of the stop valve of the present invention. The stop valve comprises a valve cover 1, a valve rod 2 and a valve core 3, wherein the valve core 3 is connected with the end part of the valve rod 2, and the valve cover 1 is sleeved on the valve rod 2. The stop valve further comprises a valve body 4, the valve body 4 is provided with a valve port 41, and the valve port 41 is arranged between an inlet 42 and an outlet 43 of the valve body 4. The valve rod 2 drives the valve core 3 to move up and down along the axis, when the valve core 3 closes the valve port 41, the inlet 42 and the outlet 43 are not communicated, and the stop valve is in a closed state; when the valve core 3 is lifted up and a gap is formed between the valve core and the valve port 41, the stop valve is in an opening state.

Since the valve stem 2 moves relative to the bonnet 1 when moving up and down, a sealing state between the valve stem 2 and the bonnet 1 is very important in the performance of the shut-off valve. Particularly, in a low temperature state, when the valve core 3 is lifted and the stop valve is in an open state, the inside of the stop valve is filled with a low temperature medium, and at this time, the performance of the sealing material is greatly changed due to the low temperature of the medium, so that the sealing property is easily lost. And the working condition of the sealing performance of the stop valve is tested at most.

In order to ensure the sealing performance between the valve rod 2 and the valve cover 1, the stop valve further comprises a first sealing element 5 and an elastic element 6, wherein the first sealing element 5 is positioned in the valve cover 1, the first sealing element 5 is sleeved on the valve rod 2, the outer peripheral surface of the valve rod 2 is provided with a section of conical surface 21, the diameter of the conical surface 21 is gradually reduced along the direction far away from the valve core 3, and the first sealing element 5 is in sealing fit with the conical surface 21; the elastic member 6 is provided on the valve rod 2, and the elastic member 6 always applies an elastic force to the valve rod 2 in a direction away from the valve body 3. Through the effort of elastic component 6 to valve rod 2, make valve rod 2 compress tightly first sealing member 5 all the time, guaranteed the sealed effect between valve rod 2 and the valve gap 1. Especially in a low temperature state, the deformation of the first sealing member 5 due to low temperature can be compensated by the force of the elastic member 6. And only be equipped with first sealing member 5 between valve rod 2 and the valve gap 1, the single-deck is sealed can reduce the leak source, guarantees sealed effect.

As shown in fig. 2 to 3, the stop valve further includes a guide sleeve 7, the guide sleeve 7 is sleeved on the valve rod 2, the guide sleeve 7 is fixed in the valve cap 1, and the first sealing member 5 is sandwiched between an end surface of the guide sleeve 7 and an inner end surface of the valve cap 1. Through setting up uide bushing 7, press from both sides tight first sealing member 5 with valve gap 1 together, guaranteed the positional stability of first sealing member 5.

The inner peripheral surface of the guide sleeve 7 is provided with a limit flange 71 protruding in the direction of the valve rod 2, an inverted conical space 9 is formed between the inner peripheral surface of the limit flange 71 and the conical surface 21 of the valve rod 2, the first seal 5 is provided with an extension 51 extending to the inverted conical space 9, and the extension 51 is in sealing engagement with the inner peripheral surface of the limit flange 71 and the conical surface 21 of the valve rod 2.

In the structure of the conventional stop valve, the problem of leakage is easily caused by unbalanced contact of seasonings and the valve rod due to the deviation of the coaxiality of the valve rod and the sealing member, so that the coaxial position relation is preferably kept all the time when the valve rod and the sealing member are contacted. By arranging the extension part 51 which can extend into the inverted conical space 9, when the coaxiality between the valve rod 2 and the first sealing element 5 is deviated, the extension part 51 is extruded, so that the leakage problem can be effectively improved; and, the contact area of first sealing member 5 and valve rod 2 is less, can provide bigger pressure under the condition of the same installation force, promotes sealed effect.

Wherein the surface of the valve cover 1 in contact with the first sealing member 5 is provided with at least one protrusion 11. The projection 11 is preferably tapered, the projection 11 forming a sealing "waterline". When the first sealing member 5 is pressed, the waterline can be pressed into the first sealing member 5, and the creep of the first sealing member 5 caused by continuous stress can be reduced, so that the sealing effect is improved.

The outer peripheral surface of the valve rod 2 is provided with a section of first guide surface 22, the first guide surface 22 is positioned between the conical surface 21 and the valve core 3, the inner peripheral surface of the guide sleeve 7 is provided with a section of second guide surface 72, the first guide surface 22 is matched with the second guide surface 72, the first guide surface 22 and the second guide surface 72 are coaxially arranged, and the cross section of the second guide surface 72 is circular. The guide sleeve 7 ensures the accuracy of the axial movement of the valve rod 2, and the guide sleeve 7 does not limit the rotation of the valve rod 2.

As shown in fig. 2 to 3, the outer peripheral surface of the valve core 3 is in threaded fit with the inner peripheral surface of the valve cover 1, the valve rod 2 is connected with the valve core 3, and the valve rod 2 drives the valve core 3 to rotate around the axis. The valve rod 2 drives the valve core 3 to rotate, so that the valve core 3 moves up and down relative to the valve cover 1, the valve core 3 is enabled to close or open the valve port 41, and the opening and closing of the stop valve are realized.

The valve core 3 is provided with an insertion hole 31 at one end facing the valve rod 2, the valve rod 2 is inserted into the insertion hole 31 of the valve core 3, the outer peripheral surface of the valve rod 2 is provided with a matching surface 23 matched with the inner peripheral surface of the insertion hole 31, and the cross section of the insertion hole 31 is non-circular, such as square.

The insertion hole 31 is coaxially arranged with the valve rod 2, the valve rod 2 can drive the valve core 3 to rotate, but the relative movement between the valve rod 2 and the valve core 3 along the axial direction is not limited, therefore, the elastic piece 6 can be placed in the valve rod 2. Specifically, the valve rod 2 has a mounting hole 24 at one end facing the valve body 3, the elastic member 6 is a compression spring 61, the compression spring 61 is placed in the mounting hole 24 of the valve rod 2, and both ends of the compression spring 61 are in contact with the bottom surface of the insertion hole 31 and the bottom surface of the mounting hole 24, respectively.

Through the mode, the compression spring 61 applies a pressing force to the valve rod 2 all the time, so that the valve rod 2 presses the first sealing element 5 all the time, and the sealing effect between the valve rod 2 and the valve cover 1 is ensured. In order to ensure the force uniformity of the first sealing element 5, the compression spring 61 is arranged coaxially with the valve rod 2, i.e. the mounting hole 24 is arranged coaxially with the valve rod 2.

In a low-temperature environment, the compression spring 61 can be made of a special low-temperature resistant stainless steel material, and the performance of the compression spring at low temperature is very stable and cannot be failed due to contact with a low-temperature medium. The elastic member 6 may be formed of other members having elastic force, in addition to the compression spring 61.

The traditional stop valve is complex in inner structure of a hand wheel, and is usually complex in connection relation with a valve rod and incapable of being detached at will. However, through the stop valve with the above structural design, the sealing element, the elastic element and the like are arranged inside the stop valve, and the hand wheel 8 arranged at the end part of the valve rod 2 outside the valve cover 1 only needs to be connected with the valve rod 2, and does not need to be accompanied by other functions. Therefore, the hand wheel 8 and the valve rod 2 can be designed to be detachably connected, the hand wheel can be independently detached and replaced by a handle, the original sealing effect cannot be influenced, and the multi-occasion use can be met.

The valve cover 1 is provided with a valve rod mounting hole 12, and the valve rod 2 penetrates through the valve rod mounting hole 12. Because the sealing structure between the valve rod 2 and the valve cover 1 is changed, in order to prevent external dust, small particles, water and the like from entering the interior of the stop valve, a dust ring 10 is additionally arranged between the valve rod 2 and the valve rod mounting hole 12. The dust ring 10 can be made of low-temperature-resistant and wear-resistant engineering plastics, and can effectively prevent impurities and the like from entering. Meanwhile, the dust ring 10 has a certain lubricating effect, and the operating torque of the stop valve is reduced.

In order to ensure the sealing performance of the stop valve, besides the sealing structure arranged between the valve rod 2 and the valve cover 1, the sealing structure is also arranged at other positions. For example, the shutoff valve further comprises a second sealing element 20, the second sealing element 20 is fixed on the end surface of the valve core 3 facing the valve port 41, and the second sealing element 20 can be in sealing fit with the valve port 41. By providing the second sealing element 20, the sealing effect between the second sealing element 20 and the valve port 41 when the shutoff valve is closed is ensured.

The connecting position of the valve body and the valve cover of the conventional stop valve is sealed by a sealing ring, and if the sealing ring is used, two leakage points are present, namely the upper part and the lower part of the sealing ring. And the sealing structure of the joint of the valve body and the valve cover of the stop valve of the embodiment is shown in fig. 4. The outer peripheral surface of the valve cover 1 is matched with the inner peripheral surface of the valve body 4, the outer peripheral surface of the valve cover 1 is provided with a first radial surface 13 protruding outwards in the radial direction, the inner peripheral surface of the valve body 4 is provided with a second radial surface 44 protruding inwards in the radial direction, the second radial surface 44 is provided with a protruding area 45 protruding towards the first radial surface 13, the protruding area 45 is in sealing fit with the first radial surface 13, and the contact part of the protruding area 45 and the first radial surface 13 forms a ring shape. By adopting the hard seal (metal seal) in metal-to-metal contact, only one leakage point is provided, and meanwhile, the protruding area 45 is designed on the second radial surface 44 of the valve body 4, so that the contact area between the second radial surface 44 and the first radial surface 13 is reduced, and when the installation torque is the same, the pressure intensity is greatly increased, and the sealing effect is favorably enhanced.

Above-mentioned stop valve has both simplified the inside structure of valve, has greatly improved the sealed effect of valve again, and the hand wheel can be dismantled and removable this characteristic, has increased customer's use scene, can satisfy customer's special operation requirement under more operating modes.

Example two

As shown in fig. 5 to 6, the second embodiment of the stop valve of the present invention is shown. Most of the structure of the stop valve of the embodiment is the same as that of the first embodiment. The difference is the arrangement of the compression spring and the manner of securing the second seal.

As shown in fig. 6, the hand wheel 8 of the shut-off valve is provided with a housing chamber 81 for housing the compression spring 61; the stop valve still includes spacing ring 30, and spacing ring 30 and valve rod 2 are located the end fixing outside valve gap 1, and spacing ring 30 lid is on the opening that holds chamber 81, and compression spring 61's both ends contact with bottom surface, the spacing ring 30 that holds chamber 81 respectively. In order to ensure the force uniformity of the first sealing element 5, the compression spring 61 is arranged coaxially with the valve rod 2, i.e. the compression spring 61 is sleeved on the valve rod 2.

Compression spring 61 is installed in the inside of hand wheel 8, and this compression spring 61 is in compression state all the time, can give valve rod 2 an ascending thrust all the time for the first sealing member 5 between valve rod 2 and the valve gap 1 is compressed tightly, prevents to reveal. Compression spring 61 installs in hand wheel 8, and compression spring 61's compression state remains unchanged throughout, can provide continuous stable thrust, and, external compression spring 61 does not need special material, can reduce the cost.

Because the compression spring 61 is installed in the handwheel 8, no complex structural design is needed between the valve core 3 and the valve rod 2, and the valve core 3 and the valve rod 2 are directly and fixedly connected.

The stop valve further comprises a fixing member 40, the fixing member 40 is fixed with the valve core 3, and the fixing member 40 clamps the second sealing member 20 on the valve core 3. If we increase the flow area of the valve, the volume of the second sealing element 20 on the valve core 3 needs to be increased, the weight of the second sealing element 20 is increased, and the second sealing element may easily fall off. And, increase the mounting 40, can prevent that second sealing member 20 from droing, when we increase the area of second sealing member 20, the condition that also can not appear droing, just so we can increase the flow area of valve.

Although the present invention has been described with reference to the preferred embodiments, it is not intended to limit the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Any modification, equivalent changes and modifications of the above embodiments according to the technical spirit of the present invention, which do not depart from the technical scope of the present invention, fall within the protection scope defined by the claims of the present invention.

Claims

1. The utility model provides a stop valve, includes valve gap, valve rod and case, the case with the end connection of valve rod, the valve gap cover is in on the valve rod, its characterized in that, stop valve still includes:

2. The shut-off valve of claim 1, wherein: the stop valve further comprises a guide sleeve, the guide sleeve is sleeved on the valve rod and fixed in the valve cover, and the first sealing element is clamped between the end face of the guide sleeve and the inner end face of the valve cover.

3. The shut-off valve of claim 2, wherein: the inner peripheral surface of the guide sleeve is provided with a limiting flange protruding towards the direction of the valve rod, an inverted conical space is formed between the inner peripheral surface of the limiting flange and the conical surface of the valve rod, the first sealing element is provided with an extending part extending to the inverted conical space, and the extending part is in sealing fit with the inner peripheral surface of the limiting flange and the conical surface of the valve rod.

4. The shut-off valve of claim 2, wherein: the outer peripheral surface of the valve rod is provided with a section of first guide surface, the first guide surface is positioned between the conical surface and the valve core, the inner peripheral surface of the guide sleeve is provided with a section of second guide surface, the first guide surface is matched with the second guide surface, the first guide surface and the second guide surface are coaxially arranged, and the cross section of the second guide surface is circular.

5. The shut-off valve of claim 1, wherein: the outer peripheral surface of the valve core is in threaded fit with the inner peripheral surface of the valve cover, the valve rod is connected with the valve core, and the valve rod drives the valve core to rotate around the axis.

6. The shut-off valve of claim 1, wherein: the valve comprises a valve core, a valve rod and a valve core, wherein one end of the valve core, facing the valve rod, is provided with an insertion hole, the valve rod is inserted into the insertion hole of the valve core, the outer peripheral surface of the valve rod is provided with a matching surface matched with the inner peripheral surface of the insertion hole, the cross section of the insertion hole is non-circular, and the insertion hole and the valve rod are coaxially arranged.

7. The shut-off valve of claim 6, wherein: the valve comprises a valve rod, a valve core and an elastic piece, wherein the valve rod is arranged in the valve core, the valve core is arranged in the valve rod, the elastic piece is a compression spring, the compression spring is placed in the valve rod, and two ends of the compression spring are respectively abutted against the bottom surface of the insertion hole and the bottom surface of the installation hole.

8. The stop valve of claim 1, further comprising a hand wheel mounted to an end of the valve stem outside the bonnet, the hand wheel being removably connected to the valve stem.

9. The shut-off valve of claim 1, wherein: the stop valve further comprises:

10. The shut-off valve of claim 1, further comprising:

11. The shut-off valve of claim 10, wherein: the stop valve also comprises a fixing piece, the fixing piece is fixed with the valve core, and the fixing piece clamps the second sealing piece on the valve core.

12. The shut-off valve of claim 1, wherein: the stop valve further comprises a valve body, the outer peripheral surface of the valve cover is matched with the inner peripheral surface of the valve body, the outer peripheral surface of the valve cover is provided with a first radial surface protruding outwards in the radial direction, the inner peripheral surface of the valve body is provided with a second radial surface protruding inwards in the radial direction, the second radial surface is provided with a protruding area protruding towards the first radial surface, the protruding area is in sealing fit with the first radial surface, and the part, in contact with the first radial surface, of the protruding area forms a ring shape.

13. The shut-off valve of claim 1, wherein: a valve rod mounting hole is formed in the valve cover, and the valve rod penetrates through the valve rod mounting hole; the stop valve still includes the dust ring, the dust ring set up in the valve rod with between the valve rod mounting hole.