Plugged needle valves and cavitation are challenges that plant engineers are often confronted with. The AS-Schneider S371 Series can help.
The Type S371 Y-pattern needle valves are used as shut-off valves in impulse lines where a low-resistance passage and less deflection of the flow are important, or where the valve must be easily rodded. A flow generally does not occur in impulse lines except when blowing off or flushing the lines. While blowing off steam lines, the small flow cross sections and high pressures can result in high flow velocities. When combined with significant deflection of flow, this can lead to cavitation and damage the valve tip and the valve seat.
The AS-Schneider S371 Series was developed specifically for this application and has a straight-through design without any deflection of flow. It has a forged valve body and all wetted parts made of stainless steel 1.4571. It comes with a graphite packing that makes it suitable for temperatures up to 550°C. It has a fully roddable 8mm bore and stems with rolled threads, back seat, and a non-rotating valve tip. The S371 Series offers a compromise between the requirements of flow characteristics and valve technology.