Sectional type high-temperature ball valve seat and ball valve

Abstract

The utility model discloses a sectional type high-temperature ball valve seat which comprises an annular main valve seat, a tungsten carbide coating is arranged on the sealing face of the main valve seat, the sectional type high-temperature ball valve seat further comprises an annular secondary valve seat connected with the main valve seat, and an alloy material surfacing layer with the hardness lower than that of the main valve seat is surfaced on the contact face of the secondary valve seat and the main valve seat. The surfacing layer and the tungsten carbide coating generate hardness difference, sufficient pre-tightening force is provided through the corrugated pipe, the secondary valve seat and the main valve seat are tightly attached all the time, and stable sealing performance is achieved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the valve field, concretely relates to a sectional high temperature ball valve seat and ball valve. BACKGROUND

[0002] At present, most of the high temperature ball valves are used in the domestic coal chemical industry and the large particle high temperature pipeline, and the high temperature resistant sealing materials such as metal sealing or ceramic sealing are usually adopted. The metal sealing can bear higher temperature and pressure, has good wear resistance and corrosion resistance, and the ceramic sealing has higher hardness and high temperature resistance, which can guarantee the sealing reliability under high temperature.

[0003] In view of the working principle and application condition of the metal valve seat, the stability and durability of the flexible graphite packing used in the sealing ring of the traditional high temperature ball valve seat cannot be guaranteed, and the sealing surface of the traditional valve seat is easy to wear under severe working conditions, which affects the service life of the valve. SUMMARY

[0004] In order to solve the above technical problems, the purpose of the utility model is to provide a sectional high temperature ball valve seat and ball valve with long service life.

[0005] In order to achieve the above purpose, the technical scheme of the utility model is: a sectional high temperature ball valve seat, which comprises an annular main valve seat, the sealing surface of the main valve seat has a tungsten carbide coating, and further comprises an annular secondary valve seat connected with the main valve seat, and the hardfacing layer of the alloy material on the contact surface of the secondary valve seat and the main valve seat is lower than that of the main valve seat.

[0006] Preferably, the hardfacing layer of the alloy material is STL.6 hardfacing layer of the alloy material.

[0007] Preferably, the secondary valve seat is provided with an annular containing groove, the hardfacing layer of the alloy material is hardfaced in the containing groove, and the hardfacing layer of the alloy material protrudes out of the groove.

[0008] Preferably, it further comprises a tail valve seat and a corrugated pipe fixedly connected with the secondary valve seat and the tail valve seat.

[0009] Further preferably, the outer side of the corrugated pipe is provided with a plurality of corrugated pipe support rings.

[0010] Further preferably, the tail valve seat is provided with a packing groove on the contact surface with the valve body, and the packing groove is provided with a graphite packing ring.

[0011] A high temperature ball valve has the sectional high temperature ball valve seat described above.

[0012] The utility model has the advantages of:

[0013] 1. The utility model discloses a valve seat is decomposed into main valve seat and porcelain muscle valve seat, and set up tungsten carbide coating on main valve seat, set up surfacing layer between two, tungsten carbide coating has high hardness, strong wear resistance and other characteristics, can be as the stable sealing coating between ball seat, the hardness difference of surfacing layer and tungsten carbide coating, provide sufficient pre-tightening force through bellow, make secondary valve seat and main valve seat always close, have stable sealing performance.

[0014] 2. The utility model discloses structure more convenient to dismount replacement, more easily realize the maintenance of valve, the replacement of sealing element, the addition of separation type structure makes main valve seat have greater flexibility, and the contact with spherical surface is more sufficient;The sealing form of tail valve seat is also more stable compared with traditional high temperature valve valve seat, and is not easy to be influenced by valve opening and closing stress. ACCURACY OF DRAWINGS

[0015] In order to more clearly illustrate the technical scheme of the embodiment of the utility model, the following will be to the embodiment description needed to use the drawing briefly introduces, the following description in the drawing is only some embodiments of the utility model, for the ordinary skilled person in the art comes, under the premise of not paying the creative labor, can also obtain other drawings according to these drawings.

[0016] The utility model will be further described in the following combining with the drawing and embodiment:

[0017] Figure 1 It is the cross section schematic view of the embodiment valve seat.

[0018] Among them: 1, main valve seat, 2, secondary valve seat, 3, bellow, 4, bellow support ring, 5, tail valve seat, 6, tungsten carbide coating, 7, alloy material surfacing layer, 8, graphite packing seal ring. SPECIFIC EMBODIMENTS

[0019] Referring to the drawing Figure 1 As shown in the drawing, a sectional high-temperature ball valve seat includes an annular main valve seat 1, and the sealing surface of the main valve seat has a tungsten carbide coating 6. The sectional high-temperature ball valve seat also includes an annular secondary valve seat 2 connected to the main valve seat 1, and the secondary valve seat 2 has an alloy material surfacing layer 7 with a hardness lower than that of the main valve seat on the contact surface with the main valve seat 1.

[0020] The alloy material surfacing layer 7 is an STL.6 alloy material surfacing layer. STL.6, i.e., Stellite 6 alloy, is a cobalt-based alloy with high wear resistance, high-temperature resistance, and corrosion resistance.

[0021] The secondary valve seat 2 is provided with an annular accommodating groove, and the alloy material surfacing layer 7 is surfacing in the accommodating groove and protrudes from the groove opening.

[0022] Also included are a tail valve seat 5 and a bellows 3 fixedly connecting the secondary valve seat 2 and the tail valve seat 6, and the outer side of the bellows 3 is provided with a plurality of bellows support rings 4.

[0023] The tail valve seat 5 is provided with a packing groove on the contact surface with the valve body (not shown in the figure), and the packing groove is provided with a graphite packing seal ring 8.

[0024] The embodiment involves four sealing areas in total:

[0025] 1. The sealing connection between the tungsten carbide coating 6 of the main valve seat 1 and the spherical surface of the ball (not shown in the figure), under the high-temperature medium working condition, the tungsten carbide coating used in the embodiment has high hardness, strong wear resistance and other characteristics, and can serve as a stable sealing coating on the main valve seat 1.

[0026] 2. The end of the secondary valve seat 2 is connected with the main valve seat 1, and the contact area is overlaid with STL.6, which has a hardness difference with the tungsten carbide coating 6 of the main valve seat 1. The bellows 3 provides sufficient pre-tightening force, so that the secondary valve seat 2 and the main valve seat 1 are always in close contact, and have stable sealing performance.

[0027] 3. The sealing between the bellows 3 and the main valve seat 1 and the tail valve seat 5, the bellows 3 has excellent sealing performance, and in the embodiment, the bellows 3 is connected with the main valve seat 1 and the tail valve seat 5 by welding, and the middle part is stabilized by the bellows support rings 4, so as to ensure that the structure has excellent sealing performance while providing sufficient support force for the entire sealing assembly.

[0028] 4. The tail valve seat 5 has a packing groove, and is tightly connected with the valve body by the pre-tightening force provided by the bellows 3. Compared with the dynamic sealing of the graphite packing of the traditional high-temperature valve seat, the packing position of the invention is closer to static sealing. The stress generated when the valve is opened and closed is buffered by the bellows 3 and the bellows support rings 4, and almost has no effect on the sealing of the tail valve seat 5, and the sealing is more stable compared with the traditional structure.

Claims

1. A segmented high temperature ball valve seat comprising an annular primary seat, the sealing face of the primary seat having a tungsten carbide coating, characterised in that: Also comprising a ring-shaped secondary valve seat connected to the main valve seat, the secondary valve seat is provided with a hardfacing layer of alloy material on the contact surface with the main valve seat, the hardfacing layer of alloy material has a lower hardness than the main valve seat.

2. A segmented high-temperature ball valve seat according to claim 1, characterized in that: The hardfacing layer of alloy material is an STL.6 hardfacing layer of alloy material.

3. A segmented high-temperature ball valve seat according to claim 1, characterized in that: The secondary valve seat is provided with a ring-shaped accommodating groove, the hardfacing layer of alloy material is hardfaced in the accommodating groove, and the hardfacing layer of alloy material protrudes out of the groove mouth.

4. A segmented high-temperature ball valve seat according to claim 1, characterized in that: Also comprising a tail valve seat and a bellows fixedly connecting the secondary valve seat and the tail valve seat.

5. A segmented high-temperature ball valve seat according to claim 4, characterized in that: The outer side of the bellows is provided with a plurality of bellows support rings.

6. A segmented high-temperature ball valve seat according to claim 4, characterized in that: The tail valve seat is provided with a packing groove on the contact surface with the valve body, and the packing groove is provided with a graphite packing seal ring.

7. A high temperature ball valve characterized by: The sectional high-temperature ball valve seat has any one of claims 1-6.

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