CN204805595U - Double pressure of ultra -low temperature gate valve sealed firmly - Google Patents

Abstract

The utility model relates to an ultra-low temperature double-row hard-sealed gate valve, which comprises a valve body, a valve seat, a gate plate, a valve stem and a valve cover. The upper end passes through the bonnet and is fixedly connected to the handwheel, and the lower end of the valve stem is connected to the gate plate in an axial floating connection; mainly, a pressure relief valve is provided between the middle cavity of the valve body and the outlet passage, and the pressure relief valve is controlled by the cone at the lower end of the valve stem. The shaped hard sealing surface and the tapered sealing surface of the inlet of the pressure relief passage on the gate plate cooperate with each other, the inlet of the pressure relief passage communicates with the middle cavity of the valve body, and the outlet of the pressure relief passage communicates with the outlet passage of the valve body. It solves the problem in the prior art that a bypass valve needs to be installed to release the pressure in the middle chamber of the valve body, and has low cost, small installation space occupation, convenient operation and labor-saving, and good sealing performance. It is suitable for ultra-low temperature, large aperture, and high-pressure medium conditions in petroleum, chemical and other industries.

Description

Ultra-low temperature double row pressure hard seal gate valve

technical field

The utility model belongs to the field of valves, in particular to a gate valve. The utility model is suitable for ultra-low temperature, large aperture, and high-pressure medium working conditions in industries such as petroleum and chemical industry.

Background technique

The structural forms of the gate valve mainly include wedge gate valve and parallel gate plate, etc. The wedge gate valve is a more commonly used structural form, and the gate plate and the valve seat are tightly sealed with a wedge-shaped wedge. When used in ultra-low temperature conditions, when the valve is closed, in order to prevent the abnormal pressure increase caused by the temperature rise of the medium in the middle chamber of the valve body, a pressure relief hole connecting the inlet passage of the valve body and the middle chamber is generally made on the gate plate. The pressure in the middle chamber is released to the outlet channel of the valve body to prevent safety accidents caused by abnormal pressure increase in the middle chamber of the valve body; under the condition of large diameter and high pressure, the high pressure in the middle chamber makes it difficult to open the gate. Traditional valves solve this problem , It is often used to install a bypass device on the valve or pipeline, which increases the cost and the installation space. It is necessary to open and close more than two valves, which makes the operation more difficult, time-consuming and laborious, increases the leakage point, and reduces the sealing performance.

Contents of the invention

The purpose of the utility model is to aim at the shortcomings of the prior art, and provide an ultra-low temperature double-row hard-sealed gate valve with low cost, small installation space, convenient operation and labor-saving, and good sealing performance.

The technical scheme of the utility model includes a valve body, a valve seat, a gate plate, a valve stem, and a valve cover. Fixed connection, axial floating connection between the lower end of the valve stem and the gate plate; mainly a pressure relief valve is provided between the middle cavity of the valve body and the outlet passage, and the pressure relief valve is formed by a tapered hard sealing surface at the lower end of the valve stem and the gate plate. The tapered sealing surfaces at the inlet of the pressure relief passage cooperate with each other, the inlet of the pressure relief passage communicates with the middle chamber of the valve body, and the outlet of the pressure relief passage communicates with the outlet passage of the valve body.

The utility model has the advantage that a pressure relief valve is provided between the middle chamber of the valve body and the outlet channel, when the valve is opened, the valve stem is lifted, and the conical hard sealing surface at the bottom of the valve stem leaves the conical sealing surface at the inlet of the pressure relief channel , the medium pressure in the middle chamber of the valve body is discharged to the outlet channel of the valve body through the pressure relief channel on the gate plate. The problem of releasing the pressure in the cavity of the valve body is low in cost, takes up little installation space, is convenient to operate, labor-saving, and has good sealing performance.

Description of drawings

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

1. Valve body, 2. Valve seat, 3. Gate plate, 4. Valve stem, 5. Bonnet, 6. Pressure relief hole, 7. Pressure relief channel.

Detailed ways

As shown in Figure 1, the ultra-low temperature double-row hard-sealed gate valve includes a valve body 1, a valve seat 2, a gate plate 3, a valve stem 4, and a valve cover 5. The gate plate 3 adopts a wedge-shaped structure, and a connecting valve is formed on the gate plate 3. The inlet channel of body 1 and the pressure relief hole 6 of the middle chamber connect the middle chamber of valve body 1 with the inlet of valve body 1 to prevent abnormal pressure rise in the middle chamber. The upper end of the valve stem 4 passes through the valve cover 5 and is fixedly connected with the handwheel. 4 The axial floating connection between the lower end and the gate plate 3, that is, the valve stem 4 can move axially in the connection port on the upper end surface of the gate plate 3. When the valve is opened, the valve stem 4 is first lifted, and then the gate plate 3 is lifted together; A pressure relief valve is provided between the middle chamber of the valve body 1 and the outlet channel, and the pressure relief valve is composed of a conical hard sealing surface at the lower end of the valve stem 4 and a conical sealing surface at the inlet of the pressure relief channel 7 on the gate plate 3, namely A valve core with a tapered sealing surface is made at the lower end of the valve stem 4, and a pressure relief passage 7 connecting the middle cavity of the valve body 1 and the outlet passage of the valve body 1 is made on the gate plate 3, and the inlet of the pressure relief passage 7 is located under the valve stem 4. In the connection port of the gate plate 3, a pressure relief valve seat with a tapered sealing surface is manufactured at the port at the entrance of the pressure relief channel 7, and the pressure relief valve seat cooperates with the valve core at the lower end of the valve stem 4 to form a pressure relief valve. The inlet of channel 7 is connected with the cavity of valve body 1, and the outlet of pressure relief channel 7 is connected with the outlet channel of valve body 1. Ram 3 is promoted, and it is easy to open.

Claims (1)

1. An ultra-low temperature double-row hard-sealed gate valve, comprising a valve body (1), a valve seat (2), a gate (3), a valve stem (4), a valve cover (5), and the gate (3) There is a pressure relief hole (6) connecting the inlet channel of the valve body (1) and the middle chamber, the upper end of the valve stem (4) passes through the valve cover (5) and is fixedly connected with the hand wheel, and the lower end of the valve stem (4) is connected to the gate plate (3 ) between the axial floating connection; it is characterized in that there is a pressure relief valve between the middle cavity of the valve body (1) and the outlet channel, and the pressure relief valve is composed of a tapered hard sealing surface at the lower end of the valve stem (4) and the gate plate (3 ) The conical sealing surfaces at the inlet of the upper pressure relief passage (7) cooperate with each other, the inlet of the pressure relief passage (7) communicates with the middle cavity of the valve body (1), and the outlet of the pressure relief passage (7) connects with the outlet passage of the valve body (1) connected.