» ASCO™ · Supplied by ACD America
ASCO™ Seat & Piston Valves
Angle-body and piston valves built for the services that punish a diaphragm: steam, hot water, aggressive liquids and high-cycling duty — pressure operated or motorized, in bronze or stainless steel.
Sizing a valve? Estimate flow, pressure drop or Cv/Kv with our free calculator.
Open the Flow Calculator →A seat valve earns its place where a solenoid diaphragm would not last. The straight-through bore of the angle body gives high flow with low pressure drop, and the piston actuator drives the disc onto the seat with force that does not depend on line pressure — so the valve closes on steam, on hot water and on media loaded with particles, cycle after cycle.
The line is organized by how the actuator is driven. Pressure-operated constructions (290D, 390, 398, X290) take a pilot air signal, which is what most plants already have at the valve. Motorized constructions (290C) need no pilot air at all and can modulate as well as switch. Function ranges from 2/2 to 3/2 — and, on the 290D, a bistable version that holds its last position. The approvals list on the 290D is the one to read if the duty is regulated: ATEX, IECEx, PED, EN 161, FDA CFR21, ISO 15848 and SIL2.
Select your valve
ASCO™ seat valves we supply
Narrow the line by port size, media and voltage — then open the series for its full technical data. Every specification below comes from the manufacturer’s published data.
290
290 (8290) Angle-Body Piston Valve
Pressure-operated angle-body piston valve with a straight-through bore in bronze or stainless steel. General service — air, inert gas, water, oil and light slurries — plus steam and hot water duty.
- 3/8" – 2 1/2"
- Cv to 14+
- Type 4 / 4X
290C
290C (8290C) Motorized Angle-Body Piston Valve
Motorized stainless-steel version of the angle-body piston valve, with proportional as well as on/off actuation. Fast closing, high flow and a design that resists water hammer.
- Motorized
- Vacuum – 10.3 bar
- IP65
290D
290D Pressure-Operated Piston Valve
The widest range of functions and connections in the seat-valve line: bronze or stainless, 2/2 and 3/2 including a bistable version, with threaded, butt-weld, clamp and flanged ends — and the longest approval list of the family.
- 2/2 · 3/2 · bistable
- Kv 2.8 – 111
- ATEX · SIL2 · PED
390
390 (8390) 3-Way Pressure-Operated Valves
The 3-way member of the pressure-operated piston family, in bronze, with 63, 90 and 125 mm piston actuators that rotate a full 360°. Built for water-hammer resistance and long life on high-cycling duty.
- 3/2 NC & NO
- Actuators 63/90/125 mm
- IP66 · SIL
398
398 (8398) 3-Way Air-Operated Piston Valve
Air-operated 3-way piston valve in stainless steel with a high-flow design, aimed at corrosive and thermal-shock environments in life science, oil & gas, chemical, water treatment and packaging.
- 1/2" – 2"
- Stainless steel
- High flow
298
298 (8298) Air-Operated Stainless Piston Valve
Two-way air-operated piston valve with a stainless-steel body, positioned for steam and hot-water service within the seat-valve line.
- 2-way
- Stainless steel
- Steam & hot water
X290
X290 Six-Port Pressure-Operated Piston Valve
Two 290 operators combined on a single six-port body, pneumatically actuated. Built for temperature-control duty such as fermentation, with tight shut-off in both directions and resistance to clogging by the medium.
- Six-port body
- Cv 5.6 / Kv 4.8
- Nickel-plated brass
No series match that combination.
Clear a filter — or tell us the duty and our application engineers will pick the valve.
Request a Quote →Series 290
290 (8290) Angle-Body Piston Valve
Pressure-operated angle-body piston valve with a straight-through bore in bronze or stainless steel. General service — air, inert gas, water, oil and light slurries — plus steam and hot water duty.
Technical data
- Port size
- 3/8", 1/2", 3/4", 1", 1 1/4", 1 1/2", 2", 2 1/2"
- Port type
- NPTF
- Actuation
- Motorized · pneumatic air pilot
- Function
- 2/2 normally closed · 2/2 normally open
- Body material
- Bronze · stainless steel
- Flow factor (Cv)
- From 2.0 to over 14.0 across the family
- Operating environment
- Indoor · outdoor
- Standards
- RoHS · Type 4 · Type 4X
Series 290C
290C (8290C) Motorized Angle-Body Piston Valve
Motorized stainless-steel version of the angle-body piston valve, with proportional as well as on/off actuation. Fast closing, high flow and a design that resists water hammer.
Technical data
- Port size
- 3/8" · 1/2" · 3/4" · DN15
- Port type
- G ISO 228/1 BSPP · ISO 7/1 RP BSPT · NPTF
- Actuation
- Motorized · proportional
- Function
- 2/2 normally closed
- Body material
- Stainless steel
- Operating pressure
- Vacuum to 10.3 bar
- Enclosure
- IP65
- Standards
- IP65 · RoHS
- Voltages
- 24 V DC · 24 V AC · 24–120 V AC/DC ranging · 48/110/115/120/208/220/230/240 V AC
Series 290D
290D Pressure-Operated Piston Valve
The widest range of functions and connections in the seat-valve line: bronze or stainless, 2/2 and 3/2 including a bistable version, with threaded, butt-weld, clamp and flanged ends — and the longest approval list of the family.
Technical data
- Port size
- 3/8", 1/2", 3/4", 1", 1 1/4", 1 1/2", 2", 2 1/2"
- Port type
- NPTF · G/RP · butt welding · clamp · flange
- Actuation
- Pneumatic air pilot
- Function
- 2/2 normally closed · 2/2 normally open · 2/2 bistable · 3/2 normally closed · 3/2 normally open
- Body material
- Bronze · stainless steel
- Flow factor (Kv)
- From 2.8 to 111
- Standards & approvals
- RoHS · REACH · ATEX · IECEx · EU 1935/2004 · FDA CFR21 · EN 161 · PED · ISO 15848 · SIL2 · EAC
Series 390
390 (8390) 3-Way Pressure-Operated Valves
The 3-way member of the pressure-operated piston family, in bronze, with 63, 90 and 125 mm piston actuators that rotate a full 360°. Built for water-hammer resistance and long life on high-cycling duty.
Technical data
- Port size
- 1/2", 3/4", 1", 1 1/4", 1 1/2", 2" · DN25–DN65 · 10 mm, 12 mm
- Port type
- G ISO 228/1 BSPP · NPTF
- Actuation
- Pressure operated · pneumatic air pilot
- Function
- 3/2 normally closed · 3/2 normally open
- Body material
- Bronze
- Actuator sizes
- 63 / 90 / 125 mm, rotatable through 360°
- Flow factor (Kv)
- From 5.19 to over 12
- Operating pressure
- Vacuum to 10.3 bar · 10.3–34.5 bar constructions
- Enclosure
- IP66 per IEC 60529
- Standards
- IEC 61508 · SIL · ATEX · ISO
Series 398
398 (8398) 3-Way Air-Operated Piston Valve
Air-operated 3-way piston valve in stainless steel with a high-flow design, aimed at corrosive and thermal-shock environments in life science, oil & gas, chemical, water treatment and packaging.
Technical data
- Port size
- 1/2", 3/4", 1", 1 1/4", 1 1/2", 2"
- Actuation
- Air-operated / pressure operated
- Function
- 3/2 normally closed · 3/2 normally open
- Body material
- Stainless steel
Series 298
298 (8298) Air-Operated Stainless Piston Valve
Two-way air-operated piston valve with a stainless-steel body, positioned for steam and hot-water service within the seat-valve line.
Technical data
- Actuation
- Pressure operated
- Function
- 2-way
- Body material
- Stainless steel
Series X290
X290 Six-Port Pressure-Operated Piston Valve
Two 290 operators combined on a single six-port body, pneumatically actuated. Built for temperature-control duty such as fermentation, with tight shut-off in both directions and resistance to clogging by the medium.
Technical data
- Port size
- 3/4"
- Port type
- G (ISO 6708)
- Actuation
- Pneumatic air pilot
- Function
- Normally closed — fluid entry under the disc
- Body material
- Nickel-plated brass
- Flow factor
- Cv 5.6 · Kv 4.8 (m³/h)
- Operating environment
- Indoor · outdoor
Need an ASCO™ seat valve?
Send us the catalog number, the port size and the service — we confirm the series, the coil and the body material, and quote it from our Orlando, FL warehouse.