English
Gate Valve
Gate valve is a kind of opening and closing member that uses a gate. The movement direction of the gate is perpendicular to the direction of the fluid. The gate valve can only be fully open or fully closed and cannot be used for regulation or throttling.
The gate valve achieves sealing through contact between the valve seat and the gate. The sealing surface is divided into two types: metal seal and elastic seal.
The structure of the gate valve can be categorized into two types:
- Non-Rising Stem
- Rising Stem
How does a gate valve work?
The working principle of a gate valve is that the gate moves up and down with the valve stem in a straight line. There is a trapezoidal thread on the valve stem. The nut at the top of the valve and the guide groove on the valve body are used to realize the up and down movement of the valve stem, and the valve stem drives the gate to move.
What are the common materials for gate valves?
Common materials for gate valves include cast iron, steel, stainless steel, copper, aluminum, etc. Different materials have different characteristics and applications.
What is a gate valve used for?
A gate valve is a valve used to cut off, open or regulate pipeline fluids. It is usually used for on/off control in systems that require linear flow and minimum flow restrictions. Widely used in water supply systems, wastewater treatment, oil and gas pipelines, and industrial applications.
Is a gate valve a flow control valve?
Gate valves are not usually used as flow control valves. Its main function is to fully open or fully close the flow of fluid in the pipeline. If the gate valve is used for adjustment, the gate will be in a half-open state. Different media will flush the gate of the gate valve during the flow process, which is likely to damage or bend the gate of the gate valve. For precise flow regulation, other types of valves, such as stop valves or throttle valves, are more suitable
What is the difference between ball valves and gate valves?
1 Differentball valve The ball valve consists of a spherical ball with a hole in the center of the ball. The ball rotates in the valve body to open or close the flow. The gate valve consists of a flat or wedge-shaped gate that moves up and down to open or close the fluid.
2 Operation method: The operation of the ball valve is relatively simple, usually opening and closing by rotating 90 degrees, which is more convenient to operate; the gate valve requires multiple turns of the handwheel to fully open or close, and the operation speed is slower.
3.Application method: Ball valves are used in applications that require fast and reliable on/off control, such as in gas pipelines, water systems, and chemical processing. Gate valves are used in applications where the valve remains fully open or fully closed for a long time, such as in water distribution systems and oil pipelines.
What are the advantages and disadvantages of gate valves?
Advantages:
1.Low flow resistance: The medium flows in a straight line through the valve body, resulting in low flow resistance.
2.Less effort required to open and close: Compared to a globe valve, the gate's movement direction is perpendicular to the flow of the medium, making operation easier.
3.Tall height and long opening/closing time: The gate valve has a long stroke, and the gate is raised and lowered by a stem.
4.Water hammer effect is not easily produced: This is due to the long closing time.
5.Bidirectional flow of the medium: The medium can flow in either direction, which makes installation easier. The channels on both sides of the valve are symmetrical.
6.Short structure length: The distance between the two connecting ends of the valve body is relatively short.
7.Simple shape and short structural length: The manufacturing process is efficient, and the valve is widely applicable.
8.Compact structure, good valve rigidity, smooth channel, low flow resistance: The sealing surface is made of stainless steel and hard alloy, providing long service life. PTFE packing ensures reliable sealing and ease of operation.
Disadvantages:
1.More complex manufacturing process: Gate valves usually have two sealing surfaces, making manufacturing more complicated compared to globe valves.
2.Friction between sealing surfaces: The relative friction between sealing surfaces leads to significant wear, and repairing worn sealing surfaces is not easy.
3.Large body cavity dimensions: This increases the structural length, size, and installation space required, especially for large-diameter gate valves, which tend to be bulky.
4.Long opening and closing time.
5.Potential for closed valve cavity pressure: In cases where needed, a pressure relief structure must be added to prevent abnormal pressure buildup in the valve cavity.