A valve seat is a crucial component of a valve. Use elastic sealing materials and a small actuator thrust to obtain a bubble-tight seal. Compressing the sealing stress of the valve seat causes the material to elastically deform and squeeze into the rough surface of the matching metal parts to block all leakage paths. The permeability of the material to the fluid is the basis for small leaks. Valve seats are an essential component of internal combustion engines, playing a crucial role in the efficient operation of the engine. These seats are located within the cylinder head and provide a sealing surface for the intake and exhaust valves. They ensure proper combustion by allowing the valves to open and close smoothly, regulating the flow of air and fuel into and out of the combustion chamber.
The role of the valve seat
It is used to support the fully closed position of the valve core and form a sealing pair.
What kind of materials are used to make valve seats?
The material used for valve seats is typically a hardened alloy, such as steel or bronze, which can withstand high temperatures and pressures. This hardness prevents excessive wear and erosion caused by constant contact with the valve face. Valve seats also need to be precisely machined to ensure a tight seal between the valve and seat.
Characteristics of valve seats
Valve seats have features of corrosion and wear resistance, long working time, high-pressure resistance, high dimensional accuracy, excellent resistance to thrust loads and high temperatures, which are suitable for most passenger vehicles, light and heavy-duty trucks, diesel engines and stationary industrial engines.
Valve discs
Valve discs, also known as valve plates or valve flaps, are essential components in various mechanical systems. These small circular discs play a crucial role in controlling the flow of fluids or gases through pipes and channels. Valve discs are typically made of durable materials such as metal or synthetic polymers to withstand the pressures and temperatures involved. Valve discs are commonly used in applications such as plumbing systems, hydraulic machinery, and even automotive engines. Their versatility lies in their ability to control both liquid and gas flows efficiently. Moreover, they can be designed to operate manually or automatically using sensors and actuators. In addition to their functional significance, valve discs also contribute to system safety. By effectively controlling fluid flow rates and pressures, they prevent potential damage caused by excessive force or overloading. This ensures that machines operate within their intended parameters while minimizing risks associated with leaks or bursts.
The feature of a skirt-type valve disc sealing ring is that the sealing between the sealing ring and the valve disc body is a double-edged line seal. The longitudinal section of the sealing part of the valve body is a trapezoidal plane space.
The role of valve discs
A spherical disc can maximize lift and minimize pressure drop. It is hardened to maximize its service life.
What kind of materials are used to make valve discs?
One commonly used material for valve discs is stainless steel. Stainless steel offers excellent resistance to corrosion, making it suitable for applications involving corrosive fluids or gases. It also provides good strength and durability, ensuring the disc can withstand high pressure and temperature conditions. Another material frequently used is bronze. Bronze valve discs offer good resistance to corrosion as well as high strength properties. They are often employed in marine applications due to their ability to resist saltwater corrosion effectively. For more specialized applications where extreme temperatures or pressures are involved, materials such as titanium or nickel alloys may be utilized. These materials exhibit exceptional strength and resistance to both heat and corrosion. In some cases, valve discs may be coated with materials like rubber or Teflon to enhance their sealing capabilities or reduce friction during operation.
In conclusion, the choice of material for valve discs depends on factors such as the type of fluid or gas being controlled, operating conditions (temperature and pressure), and desired durability. Stainless steel, bronze, titanium, nickel alloys, rubber coatings, and Teflon coatings are all common options used in manufacturing these critical components.
Valve cores
The valve core is a valve part that uses its movement to achieve the basic functions of direction control, pressure control or flow control.
Classifications of valve cores
According to the movement mode, a valve core is divided into the rotation type (at angles of 45°, 90°, 180° and 360°) and translation type (radial directions and planes).
A valve core is generally made from bronze or stainless steel, and sometimes it is also made from plastic, nylon, ceramics and glass.
The role of the valve core
The valve core in the pressure-reducing valve is one of the main components for controlling pressure.
Characteristics of valve cores
When the rotary core is rotated, the shift fork at the lower end of the rotary core drives the moving valve plate to rotate, so that the water outlet through hole on the moving valve plate corresponds to the water inlet through hole on the static valve plate. Finally, water flows from the through hole on the rotary core. This design is widely used at faucet outlets. The removable face part in the valve is used to support the fully closed position of the valve core and form a sealing pair. Generally, the valve seat diameter is the maximum flow diameter of the valve. Valve seats of butterfly valves can be made from rubber, plastic, and metal, such as EPDM, NBR, NR, PTFE, PEEK, PFA, SS315, STELLITE, etc.
The materials that should be considered when selecting a soft seated valve are as follows:
1) Fluid compatibility, including expansion, hardness loss, permeability, and degradation
2) Hardness
3) Permanent deformation
4) The degree of recovery after removed load
5) Tensile and compressive strength
6) Deformation before rupture
7) Elastic modulus
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