With over 60 years of service in the field, Elwood’s product line sets the standard by which our competitors follow. Water hydraulics is our specialty.
Our Spindle Style Descale Valve is specifically designed for the Descale environment. Widely used in the steel processing industry worldwide, providing unparalleled service and shock control. Available in normal open or closed positions, with a variety of sizes and mounting configurations, required to provide our customers with the complete solution.
FUNCTION
The main valve consists of a counter balanced spindle controlled by an internal hydraulic cylinder acting on the top of the spindle to generate the force required to close the valve, and a pneumatic air cylinder located on the bottom of the valve that is actuated to open the valve. The pneumatic cylinder’s position (open or closed) is controlled by an electrically-operated pneumatic solenoid, supplying air to the pneumatic cylinder. The opening and closing speed of the valve can be controlled by regulating the air flow entering or exiting the pneumatic cylinder.
FEATURES
• Designed to operate with low viscosity fluids and raw water • Removable Stainless Steel internal parts
• Excellent corrosion-resistance • V-Notch Shock Technology with Velocity Control Ports
• Shield Seat Design • Reversible Soft Composition Disc
• Inverse Flow Technology
V-NOTCH SHOCK TECHNOLOGY
Uses specially-designed orifices machined into seat and precision contours on the spindle assembly to control flow and reduce
hydraulic shock in the system.
As the valve is opened, fluid flows past the disc and is discharged through the special V-Notch orifices machined into the annular area of the seat located above the sealing area of the disc. (1) As the valve closes, the spindle reduces the V-Notch area, rapidly at first (2) the at a decreasing rate for each increment of spindle movement, until, (3) at the very peak of the V-Notch, flow is stopped before the disc is seated. The fluid is brought to rest gradually, eliminating harmful shock or water hammering.
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Cross-sectional view through seat area (closed position) |
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A. Reversible Composition Disc
The soft composition disc is designed to provide reliable maintenance-free drop tight
sealing around scratches or scored surfaces between the disc and seat. Damaged discs are easily reversed to provide extended seal life, reducing long term maintenance costs.
B. Inverse Flow Technology
Inverse flow concept uses the direction of fluid flow through that valve in conjunction with the operating direction of the valves spindle. The flow of the fluid through the valve is directly opposing the movement of the valve spindle as it closes. This prevents the spindle from slamming into the valve seat as the spindle approaches the fully-closed position. If fluid flow is in the same direction as the spindle movement, a large imbalance would be created, causing the spindle to slam into the valve seat.
C. Shield Seat Design
Using the different contours on the spindle assembly and the bore diameter in the seat, creates a precision metering system to control the effects of high velocities. When the spindle begins to open, the gap between the seat and the disc accelerates faster than the gap between the spindle and the bores, minimizing the effects of high velocity fluid acting on the seat and disc, providing longer valve life.
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