Low-temperature gate valve
By setting a guide cylinder, guide bracket and rolling bearing in the low-temperature gate valve, the problem of degradation of sealing caused by the valve stem being too long in ultra-low temperature conditions is solved, and the reliability of valve sealing is achieved.
Patent Information
- Application Number
- CN202421490767.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-27
- Publication Date
- 2025-04-25
- Estimated Expiration
- 2034-06-27
AI Technical Summary
In ultra-low temperature conditions such as liquefied natural gas and liquid helium, the valve cover of the existing gate valve is lengthened to dissipate the temperature, but it causes the valve stem to be too long and the vertical pressure rod to be instable, resulting in a decrease in sealing.
A low-temperature gate valve is designed. By installing a guide cylinder, a guide bracket and a rolling bearing in the valve body, the guide cylinder sleeve is arranged outside the valve stem, and the rolling bearing bears radial load to ensure stable movement of the valve stem.
It effectively prevents the instability of the vertical pressure rod caused by excessive valve stem, ensures the reliability of the valve seal and avoids the reduction of sealing.
Smart Images
Figure CN222798187U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of valves, in particular to a low-temperature gate valve. Background Art
[0002] A gate valve is a valve whose opening and closing part is a gate. The movement direction of the gate of an existing gate valve is usually perpendicular to the direction of the fluid. It can only be fully opened and fully closed, and cannot be adjusted or throttled. It is mainly used in engineering industries such as petroleum, petrochemical, electric power, and water conservancy. The gate valve mainly includes a valve body, a gate, a valve stem, a valve cover, a bracket and a drive system.
[0003] In ultra-low temperature working conditions such as liquefied natural gas and liquid helium, the valve cover of the gate valve is required to have a good heat dissipation effect to ensure that the temperature at the joint between the valve stem and the bottom of the packing is above 0°C to prevent the packing from freezing and affecting the action of the valve stem. Existing gate valves usually use a method of lengthening the valve cover neck to dissipate heat, but lengthening the valve cover neck will make the valve stem too long, causing the vertical force pressure rod to become unstable and resulting in a decrease in sealing. Summary of the invention
[0004] In view of the deficiencies in the prior art, the utility model provides a low-temperature gate valve.
[0005] The technical solution provided by the utility model is:
[0006] A low-temperature gate valve comprises a valve body, the valve body is provided with a medium flow channel, a valve seat is provided in the medium flow channel, a valve body is provided with a valve cover, a gate plate is provided in the valve body, the gate plate is provided with a sealing surface which forms a sealing fit with the valve seat, the upper end of the gate plate is connected to the valve stem, the upper end of the valve stem passes through the valve cover and is connected to the actuator, a guide mechanism is provided in the valve body, the guide mechanism comprises a guide cylinder and a guide bracket, the guide cylinder is fixed in the valve body through the guide bracket and is sleeved on the outside of the valve stem, the guide cylinder is provided with a rolling bearing, and the valve stem is passed through the rolling bearing.
[0007] The inner wall of the valve body is provided with a hook and a positioning protrusion, the guide bracket is provided with a buckle corresponding to the hook, and the guide bracket is detachably connected to the inner wall of the valve body.
[0008] A shaft sleeve is arranged between the valve cover and the valve stem.
[0009] A valve cavity is provided at the bottom of the gate plate, and a discharge hole is provided on the gate plate. The discharge hole penetrates the gate plate and extends into the valve cavity.
[0010] The gate plate is provided with flow guide grooves on both sides.
[0011] A packing assembly is provided between the valve stem and the valve cover. The packing assembly comprises packing, a packing gland and a packing pressure plate. The packing pressure plate is pressed against the packing gland by a movable bolt to thereby press the packing.
[0012] A heat sink is welded on the outer surface of the valve cover below the packing assembly.
[0013] The beneficial effects of the utility model are as follows: the utility model arranges a guide cylinder and a guide bracket in the valve body, the guide cylinder is sleeved on the outside of the valve stem, and a rolling bearing is arranged in the guide cylinder, so that the valve stem is passed through the rolling bearing. The guide cylinder can effectively prevent the vertical force pressure rod from becoming unstable due to the excessive length of the valve stem, and the rolling bearing can also bear radial loads for the valve stem, ensuring that the valve stem will not become unstable or deviate during the up and down movement, thereby ensuring the reliability of the valve sealing. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a schematic diagram of the structure of an embodiment of the utility model;
[0015] Figure 2 for Figure 1 A partial enlarged view of . DETAILED DESCRIPTION
[0016] The embodiments of the present utility model will be further described below in conjunction with the accompanying drawings.
[0017] like Figure 1-2 As shown, a low-temperature gate valve comprises a valve body 1, the valve body 1 is provided with a medium flow channel, a valve seat 2 is provided in the medium flow channel, a valve cover 12 is provided on the valve body 1, the valve body 1 and the valve cover 12 are detachably connected by bolts, which is convenient for assembly and subsequent maintenance and repair, a gate plate 3 is provided in the valve body 1, the gate plate 3 is provided with a sealing surface that forms a sealing match with the valve seat 2, the upper end of the gate plate 3 is connected to the valve stem 6, the upper end of the valve stem 6 passes through the valve cover 12 and is connected to the actuator 19, a guide mechanism is provided in the valve body 1, which comprises a guide cylinder 7 and a plurality of guide brackets 8, the guide brackets 8 are evenly distributed along the circumference of the outer ring of the guide cylinder 7, the guide cylinder 7 is fixed in the valve body 1 through the guide bracket 8 and is sleeved on the outside of the valve stem 6, the guide bracket 8 can be fixed in the valve body by welding, clamping and the like, in this embodiment, a hook 9 and a positioning protrusion 10 are provided on the inner wall of the valve body 1, the guide bracket 8 is provided with a buckle 11 corresponding to the hook 9, and the guide bracket 8 is detachably connected to the inner wall of the valve body 1, which is convenient for disassembly and assembly. Two rolling bearings 20 are arranged in the guide cylinder 7, respectively arranged at the upper end and the lower end of the guide cylinder 7. The valve stem 6 is passed through the two rolling bearings 20. The rolling bearings bear radial loads for the valve stem 6. The guide cylinder 7 plays an axial guiding and radial limiting role to ensure that the valve stem will not become unstable or deviate during the up and down movement, thereby ensuring the reliability of the valve sealing.
[0018] In this embodiment, a shaft sleeve 13 is provided between the valve cover 12 and the valve stem 6, and the upper end of the valve stem 6 is firmly mounted on the valve cover 12 through the shaft sleeve 13 to avoid the valve stem deviation caused by the excessively long neck of the valve cover 12.
[0019] In this embodiment, a valve cavity 4 is provided at the bottom of the gate plate 3, and a discharge hole 5 is provided on the gate plate 3. The discharge hole 5 penetrates the gate plate 3 and extends into the valve cavity 4. By providing the discharge hole, abnormal pressure rise in the valve cavity 4 can be effectively prevented, and the pressure balance between the valve cavity 4 and the upstream pipeline can be achieved. Guide grooves 21 are provided on both sides of the gate plate 3, which can guide and buffer the medium impacting the gate plate and reduce water hammer.
[0020] A packing assembly is provided between the valve stem 6 and the valve cover 12, including a packing 15, a packing gland 16, and a packing pressure plate 17. The packing pressure plate 17 presses the packing gland 16 through the movable bolt 18, thereby pressing the packing 15. The packing ensures that the medium will not leak from the gap between the valve stem 6 and the valve cover 12. Furthermore, a heat sink 14 is welded on the outer surface of the valve cover 12 below the packing assembly to prevent condensed water airflow from entering the packing, thereby ensuring the reliability of the valve seal.
[0021] The embodiments should not be regarded as limiting the present invention, and any non-creative improvements made based on the spirit of the present invention should be regarded as falling within the protection scope of the present invention.
Claims
1. A cryogenic gate valve, comprising a valve body, the valve body being provided with a medium flow channel, the medium flow channel being provided with a valve seat, the valve body being provided with a valve cover, the valve body being provided with a gate plate, the gate plate being provided with a sealing surface which forms a sealing fit with the valve seat, the upper end of the gate plate being connected to a valve stem, the upper end of the valve stem passing through the valve cover and connected to an actuator, characterized in that: The valve body is provided with a guide mechanism, which includes a guide cylinder and a guide bracket. The guide cylinder is fixed in the valve body through the guide bracket and is sleeved on the outside of the valve stem. The guide cylinder is provided with a rolling bearing, and the valve stem is penetrated by the rolling bearing.
2. A cryogenic gate valve according to claim 1, characterized in that: The inner wall of the valve body is provided with a hook and a positioning protrusion, the guide bracket is provided with a buckle corresponding to the hook, and the guide bracket is detachably connected to the inner wall of the valve body.
3. A cryogenic gate valve according to claim 1, characterized in that: A shaft sleeve is arranged between the valve cover and the valve stem.
4. A cryogenic gate valve according to claim 1, characterized in that: A valve cavity is provided at the bottom of the gate plate, and a discharge hole is provided on the gate plate. The discharge hole penetrates the gate plate and extends into the valve cavity.
5. A cryogenic gate valve according to claim 1, characterized in that: The gate plate is provided with flow guide grooves on both sides.
6. A cryogenic gate valve according to claim 1, characterized in that: A packing assembly is provided between the valve stem and the valve cover. The packing assembly comprises packing, a packing gland and a packing pressure plate. The packing pressure plate is pressed against the packing gland by a movable bolt to thereby press the packing.
7. A cryogenic gate valve according to claim 6, characterized in that: A heat sink is welded on the outer surface of the valve cover below the packing assembly.