CN201259014Y - Large caliber stop valve - Google Patents

Abstract

This utility model discloses a large-diameter gate valve. The valve cover assembly includes a coaxial upper cover, lower cover, and steel pipe. The lower cover is connected to the valve body. The upper and lower covers are connected to the steel pipe at both ends. The valve stem passes through the steel pipe. A bellows is installed in the annular space between the steel pipe and the valve stem. A stuffing box is located inside the port of the steel pipe facing the handwheel and contacts one end of the bellows. This technical solution achieves a double seal through the stuffing and bellows. The steel pipe and plate welded structure reduces leakage points and processing difficulty, thus lowering costs. A movable sealing element, a stainless steel bellows, is installed at the lower part of the stuffing box and the upper part of the valve cavity. The medium is sealed within the valve cavity outside the valve stem, preventing it from entering the stuffing box, thus ensuring more reliable external leakage and guaranteeing a better seal between the valve stem and the valve cover, achieving zero leakage.

Description

A large diameter globe valve

technical field

The utility model belongs to the technical field of valves, in particular, the utility model relates to a large-diameter stop valve.

Background technique

The globe valve is a common valve, generally composed of a valve body, a bonnet, a valve stem, a valve disc, and a valve stem nut. The valve disc moves along the vertical direction of the pipeline center line to realize the function of opening and closing, and mainly plays the role of cutting off the flow of the conveyed medium on the pipeline.

The bonnet of the large-diameter shut-off valve in the prior art is usually made of castings, which are prone to pores and trachoma, and the valve is prone to leakage, so it cannot be used in toxic and highly permeable medium pipelines.

In addition, the sealing methods of the stuffing box and the packing gland generally used now still inevitably have leaking gaps, because the valve stem needs to move in the linear direction and the rotary direction, and it is impossible to seal it.

Utility model content

The problem to be solved by the utility model is to provide a large-diameter stop valve with a bellows sealing structure, and its purpose is to improve the sealing effect of the large-diameter stop valve.

In order to achieve the above object, the technical scheme that the utility model takes is:

The large-diameter stop valve provided by the utility model includes a valve body, a valve cover, a valve stem, a stuffing box, a packing gland, a valve disc, a valve stem nut and a hand wheel, and the valve cover is a valve cover assembly. Wherein set coaxial upper cover, lower cover and steel pipe, described lower cover is connected with valve body, on the both ends of described steel pipe, described upper cover and lower cover are connected with steel pipe, described valve stem Through the steel pipe, a bellows is arranged in the annular space between the steel pipe and the valve stem, and the stuffing box is arranged in the port of the steel pipe facing the handwheel, and is in contact with one end of the bellows.

In order to make the utility model more perfect, the following more detailed and specific technical solutions are further proposed to obtain the best practical effect, better realize the purpose of the invention, and improve the novelty and creativity of the utility model:

A bellows seat is set in the port of the steel pipe facing the valve body, and is in contact with the other end of the bellows.

The material of the bellows is stainless steel.

The valve stem is divided into an upper valve stem and a lower valve stem, which are connected by a valve stem connection block, the upper valve stem is connected with the handwheel, and the lower valve stem is connected with the valve clack; the valve stem The connecting block connects the upper valve stem and the lower valve stem in an axial connection, and the rotation direction is free.

The position of the valve stem connection block is between the packing gland and the valve stem nut.

The utility model adopts the above-mentioned technical scheme, which can form a double seal between the filler and the bellows. The valve cover is composed of a lower cover, a steel pipe and an upper cover. The cost is reduced. As a further improvement, not only the stuffing box of a general valve is used at the valve stem, but also the lower part of the stuffing box and the upper part of the valve cavity are equipped with a movable sealing element stainless steel bellows, and the medium is sealed outside the valve stem. The cavity cannot enter the stuffing box. Therefore, the large-diameter globe valve provided by the utility model is more reliable in preventing external leakage than ordinary large-diameter globe valves, and ensures the sealing of the connection between the valve stem and the valve cover, so that the sealing effect is better. , can achieve zero leakage.

Description of drawings

The following is a brief description of the content expressed in the drawings of this specification and the marks in the drawings:

Fig. 1 is the structural representation of the utility model.

The notations used in this figure are:

1. Valve body, 2. Disc, 3. Lower stem, 4. Lower bellows seat, 5. Bellows, 6. Lower cover, 7. Steel pipe, 8. Stuffing box, 9. Upper cover, 10. Valve Rod connection block, 11, upper valve stem, 12, valve stem nut, 13, hand wheel, 14, bonnet assembly, 15, packing gland.

Detailed ways

Below with reference to the accompanying drawings, through the description of the embodiments, the specific implementation of the present utility model, such as the shape, structure, mutual position and connection relationship between each part, the function and working principle of each part, and manufacturing of the utility model. Processes, operation methods, etc. are described in further detail to help those skilled in the art have a more complete, accurate and in-depth understanding of the inventive concepts and technical solutions of the present utility model.

The structure of the utility model as shown in Figure 1, the utility model is a large-diameter stop valve, including a valve body 1, a valve cover, a valve stem, a stuffing box 8, a packing gland 15, a valve disc 2, and a valve stem nut 12 and hand wheel 13. The stuffing gland 15 compresses the stuffing in the stuffing box 8 to realize sealing.

In order to solve the problems existing in the current known technology described in the background technology part of this specification and overcome its defects, and achieve the purpose of the invention to improve the sealing effect of the large-diameter globe valve, the technical solution adopted by the utility model is:

As shown in Figure 1, the bonnet in this large-diameter shut-off valve provided by the utility model is a bonnet assembly 14, wherein a coaxial upper cover 9, a lower cover 6 and a steel pipe 7 are set, and the lower cover 6 Connected with the valve body 1, on both ends of the steel pipe 7, the upper cover 9 and the lower cover 6 are connected to the steel pipe 7, the valve stem passes through the steel pipe 7, and the annular space between the steel pipe 7 and the valve stem , a bellows 5 is provided, and the stuffing box 8 is set in the port of the steel pipe 7 facing the handwheel 13 and is in contact with one end of the bellows 5 .

The utility model provides a bellows large-diameter cut-off valve with a valve cover adopting a steel pipe and plate welding structure and adding a bellows sealing structure. The bonnet assembly 14 is welded by the lower cover 6, the steel pipe 7 and the upper cover 9, and is fixedly connected as a whole. The valve body 1 and the valve cover assembly 14 are connected by bolts. With the above technical scheme, a double seal between the packing and the bellows 5 can be formed. A movable sealing element bellows 5 is installed on the lower part of the stuffing box 8 and the upper part of the valve cavity. The medium is sealed in the valve cavity other than the valve stem and cannot enter the packing. The letter is more reliable in preventing external leakage, and ensures the sealing of the connection between the valve stem and the valve cover, so that the sealing effect is better and zero leakage can be achieved.

This corrugated pipe 5, also known as the bellows pipe, is made of multi-section metal thin pipe, has a certain expansion and contraction performance and the change performance of the inner and outer diameters, and its inner and outer diameters form a good fit with the steel pipe 7 and the valve stem. , can form internal and external gaps through proper elongation, convenient to load, and then both ends are pressurized, so that the internal and external surfaces form a tight fit with the inner hole surface of the steel pipe 7 and the outer circular surface of the valve stem respectively.

The utility model also provides reference for those skilled in the art to implement the utility model through the following several embodiments:

Embodiment one:

In the port of one end of the steel pipe 7 facing the valve body 1 described in the utility model, a bellows seat 4 is set to contact with the other end of the bellows 5 . The joints between the lower bellows seat 4 and the bellows 5, the stuffing box 8 and the steel pipe 7, the valve stem and the valve cover are welded.

Embodiment two:

The material of the bellows 5 described in the utility model is stainless steel. Stainless steel bellows have a certain degree of elasticity, strength and toughness, and at the same time have good corrosion resistance.

Embodiment three:

The valve stem described in the utility model is divided into an upper valve stem 11 and a lower valve stem 3, and is connected by a valve stem connecting block 10, the upper valve stem 11 is connected with the handwheel 13, and the lower valve stem 3 is connected with the handwheel 13. The valve disc 2 is connected; the valve stem connection block 10 connects the upper valve stem 11 and the lower valve stem 3 in an axial connection, and the rotation direction is free.

The above structure makes the upper valve stem 11 rotate during operation, and through the cooperation of the threaded structure on its surface and the valve stem nut, the upper valve stem 11 moves up and down at the same time, while the lower valve stem 3 is connected through the valve stem. The connection of the block 10 only transmits the axial movement, but not the rotational movement, so that it can drive the movement of the valve disc 2 to realize the opening and closing of the valve port.

Embodiment four:

The valve stem connecting block 10 described in the utility model is located between the packing gland 15 and the valve stem nut 12 . Guaranteed to pass through packing gland 15, stuffing box 8 and steel pipe all are the lower valve stem 3 that only does axial movement.

Embodiment five:

The working process of the large-diameter stop valve provided by the utility model is as follows:

When opening, turn the hand wheel 13 counterclockwise to drive the upper valve stem 11 to rotate and rise, and then the upper valve stem 11 drives the lower valve stem 3 and valve disc 2 to rise through the valve stem connecting block 10, and the valve is in an open state.

When closing, turn the hand wheel 13 clockwise to drive the upper valve stem 11 to rotate and descend, and then the upper valve stem 11 drives the lower valve stem 3 and valve disc 2 to descend through the valve stem connecting block 10, and the valve is in a closed state.

The technical scheme proposed by the utility model has made outstanding contributions to the prior art, has substantive features, and has made remarkable progress in technology, and has a good prospect of promotion in the industry. Therefore, the utility model has novelty, creativity and practicality.

The utility model has been exemplarily described above in conjunction with the accompanying drawings. Obviously, the specific implementation of the utility model is not limited by the above-mentioned methods, as long as various insubstantial improvements are made by adopting the method concept and technical solutions of the utility model, or Directly applying the ideas and technical solutions of the utility model to other occasions without improvement is within the protection scope of the utility model.

Claims (5)

1, a kind of heavy caliber stop valve, comprise valve body (1), valve gap, valve rod, stuffing box (8), Gland (15), flap (2), Stem Mut (12) and handwheel (13), it is characterized in that: described valve gap is valve gap assembly (14), wherein establish coaxial loam cake (9), lower cover (6) and steel pipe (7), described lower cover (6) is connected with valve body (1), on the both ends of the surface of described steel pipe (7), described loam cake (9) is connected with steel pipe (7) with lower cover (6), described valve rod passes steel pipe (7), at steel pipe (7) and valve rod annular space, if bellows (5), described stuffing box (8) be located at steel pipe (7) in the port of handwheel (13), and with described bellows (5) one end in contact.

2, according to the described heavy caliber stop valve of claim 1, it is characterized in that: described steel pipe (7) in the port of an end of valve body (1), set corrugated header (4), contact with the other end of described bellows (5).

3, according to claim 1 or 2 described heavy caliber stop valves, it is characterized in that: the material of described bellows (5) is a stainless steel.

4, according to claim 1 or 2 described heavy caliber stop valves, it is characterized in that: described valve rod is divided into upper valve rod (11) and lower valve rod (3), and by valve rod contiguous block (10) connection, described upper valve rod (11) is connected with handwheel (13), and described lower valve rod (3) is connected with flap (2); Described valve rod contiguous block (10) is axial being connected with upper valve rod (11) with lower valve rod (3) Placement, and gyratory directions all is free state.

5, according to the described heavy caliber stop valve of claim 1, it is characterized in that: the position of described valve rod contiguous block (10) is between Gland (15) and Stem Mut (12).

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