The working principle and characteristics of the globe valve
The globe valve is a tool that relies on the pressure of the valve stem to make the sealing surface of the disc and the sealing surface of the valve seat tightly fit to prevent the flow of the medium. It is a forced sealing valve and is one of the most widely used valves.
According to the direction of the passage, the globe valve is divided into four types: straight-through globe valve, direct-flow globe valve, angle globe valve and plunger globe valve.
1. Working principle of globe valve:
The stop valve, also called the cut-off valve, is one of the most widely used valves. The reason why it is popular is that the friction between the sealing surfaces is small during the opening and closing process, which is relatively durable, has a small opening height, and is easy to manufacture. , Easy maintenance, not only suitable for medium and low pressure, but also suitable for high pressure. The closing principle of the shut-off valve is to rely on the pressure of the valve stem to make the sealing surface of the disc and the sealing surface of the valve seat closely fit, preventing the flow of the medium. Our country’s valve “Sanhua” once stipulated that the flow direction of the stop valve should be from top to bottom, so there is directionality when installing. The structural length of the shut-off valve is longer than that of the gate valve, and the fluid resistance is large, and the sealing reliability is not strong during long-term operation.
As one of the most important cut-off valves, the globe valve plays an important role in the aerospace field. As an important component of aerospace equipment, the shut-off valve realizes the functions of medium transportation, cut-off, and adjustment, and its sealing performance directly affects the safe and reliable operation of aerospace equipment. Studying the influencing factors and influencing rules of the sealing characteristics of typical globe valves has guiding significance for the structural design of the valve sealing pair, thereby improving the sealing performance and reliability of the valve.
2. Globe valve characteristics:
The valve plays an important role in cutting off and throttling the medium in the pipeline. As an extremely important cut-off valve, the valve is sealed by applying a torque to the valve stem, and the valve stem is in the axial direction. The valve clack applies pressure to make the sealing surface of the valve clack closely fit the sealing surface of the valve seat, and prevent the medium from leaking along the gap between the sealing surfaces.
The sealing pair of the globe valve is composed of a valve flap sealing surface and a valve seat sealing surface, and the valve stem drives the valve flap to move vertically along the center line of the valve seat. During the opening and closing process of the globe valve, the opening height is small, the flow is easy to adjust, and the manufacturing and maintenance are convenient, and the pressure application range is wide.
Compared with another commonly used shut-off valve in industrial production, an alarm valve, the shut-off valve is simpler than the former in terms of structure, and is easy to manufacture and maintain. In terms of service life, the sealing surface of the globe valve is not easy to wear and scratch. During the opening and closing process of the valve, there is no relative sliding between the valve disc and the sealing surface of the seat, so the wear and abrasion of the sealing surface are small, so the sealing is improved. During the full closing process of the auxiliary service life stop valve, the disc stroke is small, and its height is relatively small compared to the alarm valve. The shortcoming of the globe valve is that the opening and closing torque is large and it is difficult to achieve rapid opening and closing. Because the flow passage in the valve body is relatively tortuous, the fluid flow resistance is large, and the fluid power is lost in the pipeline.
TH Valve is a professional manufacturer of butterfly valve, gate valve, check valve, globe valve, knife gate valve, ball valve with API, JIS, DIN standard, used in Oil, Gas, Marine industry, Water supply and drainage, fire fighting, shipbuilding, water treatment and other systems, with Nominal Diameter of DN50 to DN1200, NBR/EPDM/VITON, Certificates & Approvals: DNV-GL, Lloyds, DNV, BV, API, ABS, CCS. Standards: EN 593, API609, API6D
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