Piston valve 835-M

hydraulically-operatedregulatingflow-control

Overview
Hydraulically operated, piston-actuated off-line surge-anticipating control valve (Model 835-M, 800 Series) that pre-opens immediately on the pressure drop caused by abrupt pump stop to dissipate the returning high-pressure wave and eliminate surge. The valve closes smoothly, drip-tight, as quickly as the relief feature allows to prevent closing surge, and also relieves excessive system pressure. An integrated mechanical flow stem (mechanical opening limiter) provides stable flow regulation.

Features & Benefits

• Hydraulically operated, piston-actuated design – suitable for high-pressure service
• Line-pressure driven – independent operation without external actuators
• Simple, service-friendly architecture
  • Cost-effective and low-maintenance
  • Minimal external accessories required
• In-line serviceable – easy inspection and repair without pipeline removal
• Double-chamber design
  • Moderated valve reaction
  • Controlled closing curve to avoid closing surge
• Semi-straight flow, full-bore, obstacle-free path – non-turbulent flow and uncompromised reliability
• Stainless-steel raised seat – resistant to cavitation damage
• Integrated mechanical flow stem – consistent flow limiting and simple adjustment
• Optional V-Port throttling plug – improved stability at low flow rates

Typical Applications

• Pumping stations and waterworks – surge control and protection during pump shutdowns

Technical Specifications

• Model: 835-M
• Series: 800 Series
• Operation: Hydraulically operated, piston-actuated, off-line surge-anticipating control valve
• Actuation: Line pressure driven (independent operation)
• Design: Double-chamber; in-line serviceable
• Flow path: Semi-straight; obstacle-free full bore
• Seat: Stainless-steel raised seat for cavitation resistance
• Integrated: Mechanical flow stem (mechanical opening limiter)
• Optional: V-Port throttling plug for stable low-flow throttling
• Primary application: Pumping stations (surge control)
• Internal/catalogue barcode: 30587