The AVK DN250 (10") disc valve is a robust and highly versatile product, often used in the drinking water, water distribution and other applications requiring the regulation of liquid flows. This type of valve, model AVK DN250 , features a flanged configuration and meets ANSI and AWWA standards, offering guarantees of high quality and reliability.
Appearance and construction:
Visually, the AVK DN250 features a compact body made of ductile iron ( GG-GJL ), coated with a blue epoxy resin finish, which protects it from corrosion and wear. The valve features a central disc made of ductile iron coated with EPDM (rubber approved for drinking water), which ensures a perfect seal. The disc is profiled to minimize flow resistance, thus reducing wear on the internal liner and ensuring long-lasting operation even under vacuum conditions .
)(
).
Main components:
- Body : Ductile iron (GG-GJL) coated in epoxy.
- Disc : Ductile iron with EPDM coating.
- Shaft and bearings : Stainless steel with PTFE coated bearings to reduce friction.
- Seal : EPDM O-rings that guarantee a perfect and long-lasting seal.
Dimensions and specifications:
ANSI standards . The installed length (L) is 165 mm, while the overall height (H1) is 245 mm. The overall weight is around 50 kg, making it a handy valve for its category .
).
Mechanical characteristics:
This valve is designed to operate within a pressure range of PN16 , making it suitable for medium-pressure applications, such as water distribution networks. The disc is designed to rotate with low torque, thanks to the profiled edge design, which reduces mechanical stress on the internal components. The valve is designed to close in a clockwise direction and offers excellent abrasion resistance, especially in environments requiring intensive use .
).
How to use:
The valve is simple to use: using a manual or automatic actuator, the disc rotates to open or close the liquid flow. During installation, it is essential to ensure the flanges are correctly aligned to avoid sealing problems. The rotary closing mechanism ensures a reliable seal, even suitable for liquids with suspended particles(
).
Accessories:
Compatible accessories for the AVK DN250 include electric or pneumatic actuators to automate opening and closing. It can also be combined with flow meters to monitor flow and adjust operation based on operational needs .
).
Mathematical formulas for optimal use:
To optimize valve use, the formula for calculating pressure drop (ΔP) across the valve can be applied, based on factors such as nominal diameter and flow velocity. The relationship is:
ΔP=k⋅(V22g)\Delta P = k \cdot \left(\frac{V^2}{2g}\right) Δ P = k ⋅ ( 2 g V 2 )
Where:
- ΔP is the pressure drop,
- k is the valve leakage coefficient,
- V is the velocity of the fluid,
- g it's the acceleration of gravity(
).
Maintenance:
Maintenance of the AVK DN250 is relatively simple. It is advisable to periodically inspect the internal EPDM liners and O-rings for signs of wear or damage. The valve can be lubricated occasionally to ensure smooth disc movement. It is also important to check that the flanges are properly tightened and that there are no leaks .
)(
).
How to recognize a good used item:
A used AVK DN250 disc valve in good condition should have a disc with no obvious signs of corrosion or deformation. The EPDM liner should not be cracked or worn, and the actuator should operate without excessive strain. The absence of obvious leaks is a sign that the O-ring seal is still effective. It is also important to check that the actuator moves smoothly and that the valve body is not structurally damaged .
).
Sectors of use:
This valve is ideal for the water industry and drinking water distribution, but can also be used in other applications requiring the control of neutral or moderately aggressive liquid flows. It is particularly appreciated for its durable design and ease of installation and maintenance.
Why buying used is worth it:
Buying a used AVK DN250 disc valve saves costs without compromising reliability. If properly maintained, this type of valve can provide years of uninterrupted service at a much lower price than a new product.
