SLV
Manual Flanged Butterfly Valve
The SLV Manual Flanged Butterfly Valve is the flanged-body, hand-operated member of the centre-line resilient-seated series. Operated by a handle or handwheel gearbox, it provides straightforward quarter-turn isolation and throttling for general industrial and water service.
Product Benefits
- Independent flange bolting: A flanged butterfly valve bolts independently to each mating flange, so either side of the line can be opened or dismantled with the valve staying put.
- Better at line ends: That is a practical advantage over wafer valves at end-of-line positions and wherever maintenance access matters.
- Zero-leakage class: The resilient seat still delivers the series' zero-leakage shutoff class.
- Lever or gearbox: A lever gives fast, intuitive operation on smaller valves, while a handwheel gear operator provides the mechanical advantage and self-locking behaviour that larger discs need.
- Nothing to power: Manual operation keeps the installation simple and dependable, with nothing to power and little to go wrong.
Where It's Used
- Same territory as the series: It shares the application territory of the centre-line series: water supply and treatment, HVAC systems, and general industrial flow duties at modest pressures.
- Removable valve positions: Flanged ends make it a common choice for pump stations, plant rooms and buried or exposed water mains where valves must be removable.
- Small branch to large main: The size range runs from small branch lines up to very large mains.
- Gear operation as sizes grow: Gear operation is the standard approach as sizes increase.
Good to Know
- Construction: Bodies come in grey or ductile cast iron, carbon steel or stainless steel, with discs in ductile iron or stainless grades.
- Seat materials: Seats are offered in elastomers including NBR, EPDM, PTFE, VITON and silicone rubber, and seat material drives chemical and temperature suitability, so match it to the medium first.
- Upgrade path: The standardised top flange means a manual valve can later accept a gear operator or actuator without replacing the valve body.
- Renewable wear part: As with all resilient-seated designs, the seat is the renewable wear part.
- Avoid near-closed throttling: Sustained throttling near the closed position wears the seat fastest, so size the valve to operate at moderate openings where possible.
