TWM606702U - High-pressure needle valve with split valve stem - Google Patents

Abstract

The model relates to a high-pressure needle valve with a split valve stem, which comprises a valve body, a valve stem, a valve core, a packing nut, a packing, a valve seat and a handle. The valve seat is screwed and fixed on the lower end of the valve body, and a medium inlet, a medium outlet and a transition cavity used to fit the valve core are opened on the valve seat. A valve stem hole for inserting the valve stem is opened in the valve body. The packing is built in the valve stem hole and is filled around the outer side wall of the valve stem. The packing nut is screwed into the stem hole by means of a thread pair, and the packing is compressed. The valve stem and the packing nut are also screwed together by means of a thread pair. The valve stem is arranged in a split structure, which includes an upper valve stem and a lower valve stem. In this way, when the on/off operation of the high-pressure needle valve is adjusted by rotating the valve stem, at the same time, the filler exerts a certain friction force on the side wall of the lower valve stem and prevents it from rotating, so that the lower valve stem only It can perform axial movement, which greatly reduces the wear rate of the packing.

Description

High pressure needle valve with split valve stem

The model relates to the technical field of high-pressure needle valve manufacturing, in particular to a high-pressure needle valve with a split valve stem.

The high-pressure needle valve has the advantages of small fluid resistance, simple structure, compactness, reliable sealing, convenient operation and maintenance, and wide application range. It is widely used in machinery, chemical, petroleum and other industries. Its valve core is driven by the valve stem, and Move up and down along the axis of the valve stem to realize the opening/closing of the valve.

In the prior art, the valve stem is sealed by squeezing the packing nut along the axial direction of the packing to force the packing to deform in the radial direction, thereby achieving the purpose of sealing. The valve stem is an integrated structure, and it is screwed with the packing nut by means of a thread pair (as shown in Figure 1), but there are the following problems: in the actual operation process, the valve stem is rotated to achieve the valve core relative to The position of the transition cavity is changed to realize the on/off purpose of the medium inlet and the medium outlet. However, in the above process, the side wall of the valve stem always has circumferential friction with the packing, which greatly increases the wear rate of the packing. If things go on like this, the gap between the packing and the valve stem will increase day by day, which will affect the matching accuracy of the two, resulting in The fluid medium overflows through the thread pair of packing nut and valve stem, and the thread pair of packing nut and valve body, which affects the sealing performance of the high-pressure needle valve. In addition, when the thread pair is corroded by the fluid medium, it is prone to rust, thus Affect the adjustment flexibility of the high pressure needle valve. Therefore, it is urgent for technicians to solve the above problems.

The technical problem to be solved by the new model is to provide a high-pressure needle valve with a split valve stem, which has a simple structure design and a long-term effect to ensure the matching accuracy of the valve stem and the packing.

In order to solve the above technical problems, the present invention relates to a high-pressure needle valve with a split valve stem, which includes a valve body, a valve stem, a valve core, a packing nut, a packing, a valve seat and a handle. The valve seat is screwed and fixed on the lower end of the valve body, and a medium inlet, a medium outlet and a transition cavity used to fit the valve core are opened on the valve seat. A valve stem hole for inserting the valve stem is opened in the valve body. The packing is built in the valve stem hole and is filled around the outer side wall of the valve stem. The packing is compressed by a packing nut. Correspondingly, a first internal thread is provided on the inner wall of the upper half of the valve stem hole, and a first external thread that matches the above-mentioned first internal thread is provided on the outer side wall of the packing nut. . The valve core is arranged at the lowest end of the valve stem. In addition, a second internal thread is provided on the inner side wall of the packing nut. Correspondingly, the outer wall of the valve stem is provided with a second external thread that matches the second internal thread, so that the valve can be changed by rotating the valve stem. The position of the core relative to the transition cavity so as to realize the on/off of the medium inlet and the medium outlet. The valve stem is arranged in a split structure, which includes an upper valve stem and a lower valve stem. A T-shaped plug connector is provided on the top surface of the lower valve stem, and correspondingly, a T-shaped plug-in slot adapted to the T-shaped plug connector is opened on the bottom surface of the upper valve stem. There is a clearance fit between the T-shaped plug joint and the T-shaped plug-in groove, so that the lower valve rod can rotate freely relative to the upper valve rod.

As a further improvement of the above technical solution, friction reducing protrusions are provided on the top surface of the T-shaped plug connector. In the actual working process, the friction reducing protrusion always abuts against the top wall of the T-shaped plug-in groove.

As a further improvement of the above-mentioned technical solution, strip-shaped through grooves are provided on the top surface of the above-mentioned friction-reducing protrusions for embedding lubricating graphite.

As a further improvement of the above technical solution, the top surface of the friction reducing protrusion is spherical.

As a further improvement of the above technical solution, the filler is formed by stacking a plurality of packing gaskets, and the material is graphite fiber.

As a further improvement of the above-mentioned technical solution, the above-mentioned high-pressure needle valve with a split valve stem further includes a lock nut which is adapted to the first external thread and which is always pressed against the top surface of the valve body.

As a further improvement of the above technical solution, the second external thread is a trapezoidal thread, and a wear-resistant coating is provided on its surface.

As a further improvement of the above technical solution, the valve core and the lower valve stem are integrally formed.

Of course, as a modification of the above technical solution, a receiving cavity can also be opened at the end of the lower valve stem for inserting the valve core. Elastic rubber balls are arranged on the top of the containing cavity and directly above the valve core.

As a further improvement of the above technical solution, a valve stem installation hole is opened in the middle of the side wall of the handle. The handle is fixed to the valve stem by means of a locking screw. Correspondingly, the corresponding position of the upper valve stem is provided with an abutting plane. A threaded hole adapted to the locking screw is opened along the end surface of the handle, and is orthogonal to the valve stem installation hole.

As a further improvement of the above technical solution, the number of threaded holes is set to 2, and they are symmetrically distributed on the left and right sides of the handle.

Compared with the high-pressure needle valve with a traditional design structure, in the technical solution disclosed in the present invention, the valve stem adopts a split structure, and the lower valve stem can rotate freely relative to the upper valve stem. In this way, when the on/off operation of the high pressure needle valve is adjusted by rotating the valve stem, at the same time, the filler exerts a certain friction force to the side wall of the lower valve stem, thereby preventing the lower valve stem from rotating in a circumferential direction. , So that the lower valve stem only moves axially in the up and down direction relative to the packing, thereby greatly reducing the wear rate of the packing, ensuring the accuracy of matching with the valve stem, and ensuring the tightness of the high-pressure needle valve.

1: Valve body

2211: Friction reduction bump

63: transition cavity

11: Stem hole

222: receiving cavity

7: handle

2: Valve stem

3: Spool

71: Stem mounting hole

21: Upper stem

4: Packing nut

72: Through the threaded hole

211: T-shaped plug into the slot

5: filler

8: lock nut

212: Lean against the cut plane

6: Valve seat

9: Elastic rubber ball

22: Lower stem

61: Medium inlet

10: Locking screw

221: T-shaped plug connector

62: Medium outlet

Figure 1 is a schematic view of the structure of a high-pressure needle valve in the prior art.

Figure 2 is a schematic structural view of the first embodiment of the high-pressure needle valve with a split valve stem in the present invention.

Fig. 3 is a structural diagram of the upper valve stem in the first embodiment of the high-pressure needle valve with a split valve stem according to the present invention.

Fig. 4 is a schematic structural view of the lower valve stem in the first embodiment of the high-pressure needle valve with a split valve stem according to the present invention.

Fig. 5 is a schematic structural view of a second embodiment of the high-pressure needle valve with a split valve stem in the present invention.

Fig. 6 is a partial enlarged view of I in Fig. 5.

Fig. 7 is a schematic structural view of the lower valve stem in the second embodiment of the high-pressure needle valve with a split valve stem according to the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", etc. is based on the orientation or positional relationship shown in the drawings, and is only for It is convenient to describe and simplify the description of the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

The technical solution disclosed in the present invention will be described below with examples. Figure 2 shows a schematic structural view of the first embodiment of the high-pressure needle valve with a split valve stem in the present invention, which is mainly composed of valve body 1, valve stem 2, The valve core 3, the packing nut 4, the packing 5, the valve seat 6 and the handle 7 are composed of several basic parts. Among them, the valve seat 6 is screwed and fixed to the lower end of the valve body 1 by means of a thread pair, and is provided with The medium inlet 61, the medium outlet 62 and the transition cavity 63 used to fit the valve core 3. The medium inlet 61 and the medium outlet 62 are distributed on the left and right sides of the transition cavity 63, and they are all connected to the transition cavity 63. A valve stem hole 11 into which the valve stem 2 is inserted is opened in the valve body 1. The packing 5 is built in the valve stem hole 11 and is filled around the outer side wall of the valve stem 2. The packing 5 is compressed by the packing nut 4. Correspondingly, a first internal thread is provided on the inner wall of the upper half of the valve stem hole 11, and the outer side wall of the packing nut 4 is provided with a suitable first internal thread. The first external thread. The valve core 3 is arranged at the lowest end of the valve stem 2. In addition, the inner wall of the packing nut 4 is provided with a second internal thread. Correspondingly, the outer wall of the valve stem 2 is provided with a second external thread that matches the above-mentioned second internal thread, so that the valve stem 2 can be rotated The position of the valve core 3 relative to the transition cavity 63 can be changed, so as to realize the on/off of the above-mentioned medium inlet 61 and the medium outlet 62.

What needs to be emphasized here is that the above-mentioned valve rod 2 is configured as a split structure, which includes an upper valve rod 21 and a lower valve rod 22. The lower valve stem 22 can perform free rotation relative to the upper valve stem 21 (as shown in FIG. 2). The valve core 3 is directly integrally formed on the lower end of the lower valve stem 22. In this way, when the on/off operation of the high pressure needle valve is adjusted by rotating the valve stem 2, at the same time, the packing 5 applies a certain friction force to the side wall of the lower stem 22, thereby preventing the occurrence of the lower stem 22. Circumferential rotation movement makes the lower valve stem 22 only move up and down in the axial direction relative to the packing 5, thereby greatly reducing The wear speed of the packing is ensured, the matching accuracy with the valve stem 2 is ensured, and the tightness of the high-pressure needle valve is ensured.

As a further refinement of the above-mentioned split structure, a T-shaped plug connector 221 (as shown in FIG. 4) can be provided on the top surface of the lower valve stem 22, and correspondingly, the bottom surface of the upper valve stem 21 is provided with the same T-shape The plug connector 221 is matched with a T-shaped plug into the slot 211 (as shown in FIG. 3). There is a clearance fit between the T-shaped plug joint 221 and the T-shaped plug-in groove 211, so that the lower valve stem 22 can rotate freely relative to the upper valve stem 21.

In order to reduce the frictional force of the lower valve stem 22 relative to the upper valve stem 21 during the movement, and to improve the flexibility of the movement of the two, it is also possible to provide a friction reducing protrusion 2211 on the top surface of the T-shaped plug connector 221 ( As shown in Figure 4). In the actual working process, the friction reducing protrusion 2211 always abuts against the top wall of the T-shaped insertion groove 211.

As a further optimization of the above-mentioned technical solution, a strip-shaped through groove may be provided on the top surface of the above-mentioned friction reducing protrusion 2211 for embedding lubricating graphite (not shown in the figure). It is known that the lubricating graphite itself has a good self-lubricating shape, which can effectively reduce the friction coefficient of the friction protrusion 2211 relative to the upper valve stem 21, thereby increasing the service life of the upper valve stem 21 and the lower valve stem 22. Of course, the top surface of the aforementioned friction reducing protrusion 2211 can also be set in a spherical shape (as shown in FIG. 2).

In order to improve the wear resistance of the packing 5 and reduce its wear rate relative to the valve stem 2, for this reason, the above-mentioned packing 5 is preferably made up of multiple packing gaskets (as shown in Figure 2), and Its material is graphite fiber. Of course, other types and models of fillers can also be selected in actual conditions.

Furthermore, the above-mentioned high-pressure needle valve with a split valve stem further includes a lock nut 8 which is adapted to the first external thread and which is always pressed against the top surface of the valve body 1 (as shown in Figure 2) . when After the packing nut 8 is assembled with respect to the valve body 1, it is locked and fixed by the lock nut 8 in time to prevent loosening during later use.

Furthermore, the external thread provided on the outer side wall of the valve stem 2 and the internal thread provided on the inner side wall of the packing nut 4 are preferably trapezoidal threads with a tooth profile angle of 30°. It is known that the trapezoidal thread has high strength in use and self-locking characteristics, which effectively ensures the stability of the relative position of the valve stem 2 relative to the packing nut 4, thereby ensuring the constancy of the position of the valve core 3 relative to the transition chamber 63 . In order to reduce the wear rate and increase the service life, a wear-resistant coating (not shown in the figure) can also be added on the thread pair between the valve stem 2 and the packing nut 4.

Figure 5 shows a schematic structural view of the second embodiment of the high-pressure needle valve with a split valve stem in the present invention. Compared with the first embodiment described above, the difference between the valve core 3 and the lower valve stem 22 is The connection is made in a detachable manner, which can be specifically implemented with reference to the following scheme: the upper valve stem 21 is exactly the same as in the above-mentioned first embodiment. A receiving cavity 222 (as shown in FIG. 7) is opened at the end of the lower valve stem 22 for inserting the valve core 3 described above. An elastic rubber ball 9 is provided on the top of the accommodating cavity 222 and directly above the valve core 3 (as shown in FIG. 6). The elastic rubber ball 9 always exerts a certain elastic pressing force on the top wall of the valve core 3. In this way, when the lower valve stem 22 is deflected relative to the axial center line of the valve stem hole 11, the valve core 3 is in the elastic rubber Under the action of the ball 9, the offset angle can be adjusted by itself to ensure the smoothness of its own movement and the reliable sealing of the transition cavity 63 as much as possible.

Finally, a valve stem mounting hole 71 (as shown in Fig. 2) can also be opened in the middle of the side wall of the handle 7. The handle 7 is fixed to the valve stem 2 by means of the locking screw 10. Correspondingly, the upper valve stem 21 is provided with an abutting plane 212 at the corresponding position. A threaded hole 72 is provided along the end surface of the handle 7 to match the locking screw 10 and is orthogonal to the valve stem mounting hole 71. In this way, on the premise of ensuring the reliability of the connection between the handle 7 and the valve stem 2, the separation of the two is as low as possible. Time, reduce the difficulty of later maintenance. Even further optimization, the number of the above-mentioned threaded holes 72 is set to 2, and they are symmetrically distributed on the left and right sides of the handle 7 (as shown in FIG. 2).

The above description of the disclosed embodiments enables those skilled in the art to realize or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined in this document can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown in this article, but should conform to the widest scope consistent with the principles and novel features disclosed in this article.

1: Valve body

61: Medium inlet

11: Stem hole

62: Medium outlet

2: Valve stem

63: transition cavity

21: Upper stem

7: handle

22: Lower stem

71: Stem mounting hole

3: Spool

72: Through the threaded hole

4: Packing nut

8: lock nut

5: filler

10: Locking screw

6: Valve seat

Claims (10)

A high-pressure needle valve with a split valve stem, comprising a valve body, a valve stem, a valve core, a packing nut, a packing, a valve seat, and a handle; the valve seat is screwed and fixed on the lower end of the valve body, and A medium inlet, a medium outlet, and a transition cavity used to fit the valve core are opened on it; a valve stem hole for the valve stem to be inserted is opened inside the valve body; the packing is built into the valve Inside the stem hole and around the outer side wall of the valve stem for filling; the packing is compressed by the packing nut, correspondingly, a first internal thread is provided on the inner wall of the upper half of the stem hole , The outer side wall of the packing nut is provided with a first external thread that is adapted to the first internal thread; the valve core is arranged at the lowest end of the valve stem; in addition, in the inner side of the packing nut The side wall is provided with a second internal thread. Correspondingly, a second external thread that matches the second internal thread is provided on the outer wall of the middle section of the valve stem, so that the valve stem can be rotated to change the The position of the valve core relative to the transition cavity, so as to realize the on/off of the medium inlet and the medium outlet, the valve stem is arranged in a split structure, which includes an upper valve stem and a lower valve stem; The top surface of the lower valve stem is provided with a T-shaped plug connector. Correspondingly, a T-shaped plug-in slot adapted to the T-shaped plug connector is opened on the bottom surface of the upper valve stem; the T-shaped plug connector There is a clearance fit with the T-shaped plug-in groove, so that the lower valve rod can rotate freely relative to the upper valve rod. As described in claim 1, the high-pressure needle valve with a split valve stem is provided with a friction-reducing protrusion on the top surface of the T-shaped connector; in the actual working process, the friction-reducing protrusion always abuts Insert into the top wall of the groove in the T-shape. According to claim 2 of the high-pressure needle valve with a split valve stem, a strip-shaped through groove is opened on the top surface of the friction-reducing protrusion for inlaying lubricating graphite. In the high-pressure needle valve with a split valve stem according to any one of claims 2-3, the top surface of the friction reducing protrusion is spherical. According to the high-pressure needle valve with a split valve stem according to any one of claims 1-3, the packing is formed by stacking a plurality of packing gaskets, and the material is graphite fiber. The high-pressure needle valve with a split valve stem according to any one of claims 1-3, further comprising a lock nut which is adapted to the first external thread and which is always pressed against the valve The top surface of the body. In the high-pressure needle valve with a split valve stem according to any one of claims 1-3, the second external thread is a trapezoidal thread, and a wear-resistant coating is provided on its surface. In the high-pressure needle valve with a split valve stem according to any one of claims 1-3, the valve core and the lower valve stem are integrally formed. The high-pressure needle valve with a split valve stem according to any one of claims 1 to 3, wherein a receiving cavity is opened at the end of the lower valve stem for inserting the valve core; in the receiving cavity An elastic rubber ball is arranged on the top of the valve and directly above the valve core. The high-pressure needle valve with a split valve stem according to any one of claims 1-3, a valve stem mounting hole is opened in the middle of the side wall of the handle; the handle is connected to the valve by means of a locking screw For the fixing of the rod, correspondingly, the corresponding position of the upper valve rod is provided with an abutting and cutting plane; along the end surface of the handle is provided with a through threaded hole adapted to the locking screw, and it is connected to the The valve stem mounting holes are orthogonal; the number of the threaded holes is set to 2, and they are symmetrically arranged on the left and right sides of the handle.

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