Page Category: Actuators
Page Category: Actuators
A local/remote station serves as an interface for controlling valves, offering seamless transition between computer-based and manual operation modes. Designed within a compact NEMA Type 4X fiberglass polyester enclosure with stainless steel trim, it ensures protection and durability. Equipped with essential features including selector switches for open/close control and hand-off-auto operation, it grants users flexibility to override computer control when necessary. Indicator lights signal valve status, and three dry contact relays facilitate open confirmation, closed confirmation, and alarm signaling. With these features, the station provides efficient valve control solutions for industrial applications.
Ideal Applications Include:
Maintenance, manual control, protection against computer signal loss
- For use with Series 19 Electric Actuators
- NEMA Type 4X enclosure constructed of fiberglass polyester
- Stainless steel trim
- For use with with Series 19 Electric Actuators
- NEMA Type 4X enclosure constructed of fiberglass polyester
- Stainless steel trim
- Captive cover gasket
- Captive cover screws
- Two position selector switch (open/close)
- Three position selector switch (hand/off/auto)
- Terminal block for the landing of the Series 19 electric actuator flying leads
- Three indication lights (green – open; red – closed; blue – alarm)
- Three dry relays – SPDT, 10A (open confirmation [CR1], closed confirmation [CR2], alarm [CR3])
- Series 19 CAV
- Series 19 SAV
- Series 19 MAV
- Contact factory for specific applications
Page Category: Actuators
The Series 19 modulating failsafe combines the features of a modulating unit with the reliability of a failsafe unit. With all of the same features of the modulating unit, the modulating failsafe employs a capacitor discharge design for the failsafe ability. When the power supply is lost, the failsafe system will cycle the valve to a predetermined position (open, closed, or as is).
Resources:
Data Sheets
Specifications:
Sizes:
S20, S50, S110, S400
Amp Draw:
0.34 Amp for S20, 0.39 Amp for S50,
1.24 Amp for S110, 1.83 Amp for S400
Cycle Time:
Per 90 degrees: 10 seconds
Torque:
177 in-lbs to 3540 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter color-coded cable
Enclosure:
NEMA 4X
Voltage:
95 VAC to 265 VAC 1Ph 50/60 Hz
24 AC/DC
Max Temp:
150° F
Valve/Actuator Packages
- Compact: Perfect for OEM and skid manufacturers
- OLED Screen: Displays input command, position status, alert conditions
- Push Buttons: Used to calibrate/adjust end positions and operate local controls
- Multi-voltage: 95 VAC to 265 VAC or 24 VAC/VDC
- Motor: Reversing, brushless DC motor
- Gear Train: Permanently lubricated steel gears
- Corrosion Resistant Enclosure: NEMA 4X enclosure with stainless steel trim
- ISO mounting configuration
- Electrical Connection: NEMA 4X cable gland with two-meter cable length
- Position Indication: Highly visible beacon position indicator
- LED Position Indication: RED closed, GREEN open, BLUE fault
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Selectable Control Signal: User can select 4-20 mA, 0-20 mA, 0-10 VDC, 2-10 VDC, or 1-5 VDC (size 20 is specifically a current control signal or a voltage control signal)
- Reverse Acting: User can select standard operation or reverse acting
- Selectable Fail Position: If control signal is lost, the unit can be calibrated to fail as is, fail open, or fail close
- Transmitter: Current or voltage transmitter (matching the control signal) is standard equipment
- Capacitor Discharge System: A capacitor is used in place of batteries for failsafe mode
- QR Code: Links to user manual; includes wiring schematic
- RoHS Compliant
Page Category: Actuators
An on/off Series 19 electric actuator provides maintenance- and trouble-free operation in an on/off application.
Resources:
Data Sheets
- Data sheet – Series 19 MAV Modulating Actuator for Diaphragm Valve (24 VAC/VDC)
- Data sheet – Series 19 MAV Modulating Actuator for Diaphragm Valve (95 VAC to 265 VAC)
- Data sheet – Series 19 MAV Modulating Actuator for Gate Valve (95 VAC to 265 VAC)
Ideal Applications Include:
Remote locations, locations with no air supply, colder temperatures, smaller valves, low cost applications
Specifications:
Sizes:
S20, S50
Amp Draw:
0.96 Amp for S20, 1.2 Amp for S50 (24 VAC/VDC)
0.24 Amp for S50 (95 VAC to 265 VAC)
Cycle Time:
Per cycle: 13 to 100 seconds
Torque:
177 in-lbs to 442 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter cable
Enclosure:
NEMA 4X PC/PET enclosure with stainless steel trim
Valve/Actuator Packages
Type-14 Diaphragm Valve:
- Compact: Perfect for OEM and skid manufacturers
- OLED Screen: Displays input command, position status, alert conditions
- Push Buttons: Used to calibrate, local controls
- Multi-voltage: 24 VAC/VDC
- Motor: Reversing, brushless DC motor
- Gear Train: Permanently lubricated steel gears
- Corrosion Resistant Enclosure: NEMA 4X PC/PET enclosure with stainless steel trim
- Electrical Connection: NEMA 4X cable gland with two-meter cable
- Visual Position Indication: Flat disc position indicator
- LED Position Indication: RED closed, GREEN open, BLUE fault
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Selectable Control Signal: User can select 4-20 mA, 0-20 mA, 0-10 VDC, 2-10 VDC, or 1-5 VDC (size 20 is specifically a current control signal or a voltage control signal)
- Reverse Acting: User can select standard operation or reverse acting
- Selectable Fail Position: If control signal is lost, the unit can be calibrated to fail as is, fail open, or fail close
- Transmitter: Current or voltage transmitter (matching the control signal) is standard equipment
- Alarm Contacts: Dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC for alarm status (over torque, as an example)
- QR Code: Links to user manual; includes wiring schematic
- Space Heater: Internally wired to limit condensation
- CE Compliant: All actuators are CE labeled and compliant
- 70% Duty Cycle: Extended duty cycle is ideal for high cycling applications
- Simple Wiring: Wiring technique is the same for all voltage units
- Local Controls: Used with OLED and push buttons, a user can locally open or close units via password
Type-C Gate Valve:
- Compact: Perfect for OEM and skid manufacturers
- OLED Screen: Displays valve position, alarms (such as an over torque condition)
- Push Buttons: Used to calibrate/adjust end positions, local controls
- Multi-voltage: 95 VAC to 265 VAC, 24VAC/VDC
- Motor: Reversing, brushless DC motor
- Gear Train: Permanently lubricated steel gears
- Corrosion Resistant Enclosure: NEMA 4X PC/PET enclosure with stainless steel trim
- ISO mounting configuration
- Electrical Connection: NEMA 4X cable gland with two-meter cable
- Visual Position Indication: Flat disc position indicator
- LED Position Indication: RED closed, GREEN open, BLUE fault
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Auxiliary Contacts: Open and closed dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC
- Alarm Contacts: Dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC for alarm status (over torque, as an example)
- QR Code: Links to user manual; includes wiring schematic
- Space Heater: Internally wired to limit condensation
- CE Compliant: All actuators are CE labeled and compliant
- 70% Duty Cycle: Extended duty cycle is ideal for high cycling applications
- Simple Wiring: Wiring technique is the same for all voltage units
- Local Controls: Used with OLED and push buttons, a user can locally open or close units via password
- Data sheet – Series 19 MAV Modulating Actuator for Diaphragm Valve (24 VAC/VDC)
- Data sheet – Series 19 MAV Modulating Actuator for Diaphragm Valve (95 VAC to 265 VAC)
- Data sheet – Series 19 MAV Modulating Actuator for Gate Valve (95 VAC to 265 VAC)
- User Manual | Spanish
- Specification – MAV Modulating
Sales Resources:
Page Category: Actuators
Series 19 modulating actuators provide precise flow for your process line or system. The actuators use voltage or current control signals to accurately modulate the valve to the required position, while simultaneously providing voltage or current position feedback.
Resources:
Data Sheets
Specifications:
Sizes:
S20, S50, S110, S400
Amp Draw:
0.34 Amp for S20, 0.39 Amp for S50, 1.24 Amp for S110, 1.83 Amp for S400
Cycle Time:
Per 90 degrees: 10 seconds
Torque:
177 in-lbs to 3540 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter color-coded cable
Enclosure:
NEMA 4X
Voltage:
95 VAC to 265 VAC 1Ph 50/60 Hz
24 AC/DC
Max Temp:
150° F
Valve/Actuator Packages
- Compact: Perfect for OEM and skid manufacturers
- OLED Screen: Displays input command, position status, alert conditions
- Push Buttons: Used to calibrate/adjust end positions and operate local controls
- Multi-voltage: 95 VAC to 265 VAC or 24 VAC/VDC
- Motor: Reversing, brushless DC motor
- Gear Train: Permanently lubricated steel gears
- Corrosion Resistant Enclosure: NEMA 4X enclosure with stainless steel trim
- ISO mounting configuration
- Electrical Connection: NEMA 4X cable gland with two-meter cable length
- Position Indication: Highly visible beacon position indicator
- LED Position Indication: RED closed, GREEN open, BLUE fault
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Selectable Control Signal: User can select 4-20 mA, 0-20 mA, 0-10 VDC, 2- 10 VDC, or 1-5 VDC (size 20 is specifically a current control signal or a voltage control signal)
- Reverse Acting: User can select standard operation or reverse acting
- Selectable Fail Position: If control signal is lost, the unit can be calibrated to fail as is, fail open, or fail close
- Transmitter: Current or voltage transmitter (matching the control signal) is standard equipment
- Alarm Contacts: Dry contacts rates 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC for alarm status (over torque, as an example)
- Space Heater: Internally wired to limit condensation
- QR Code: Links to user manual; includes wiring schematic
- RoHS Compliant
- Data Sheet – Series 19 SAV Modulating Actuator
- Data Sheet – Series 19 SAV Modulating Actuator Type-21
- Data Sheet – Series 19 SAV Modulating Actuator Type-21a SST
- Data Sheet – Series 19 SAV Modulating Actuator Type-23
- Data Sheet – Series 19 SAV Modulating Actuator Type-57P
- User Manual | Spanish
- Specification – SAV Modulating
Sales Resources
Page Category: Actuators
The basic Series 19 CAV Com Pack® is a mechanical-type actuator available as an on/off unit. The CAV Com Pack® mounts on Asahi/America’s Type-27 Omni® ball valves, Type-21 ball valves and Type-23 Multiport™ ball valves to provide smooth operation in a compact and lightweight package. The Com Pack® Series 19 fits Omni ball valve sizes 3/8” – 2”, Type-21 and Type-23 ball valves sizes 1/2″ – 2″ and has a cycle time of 10 seconds per 90 degrees.
Resources:
Data Sheets
Specifications:
Size:
C20 for 3/8″ – 2″ Omni® Type-27 Ball Valves
Amp Draw:
0.18 Amp
Cycle Time:
Per 90 degrees: 10 seconds
Torque:
177 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter color coded cable
Enclosure:
NEMA 4X
Voltage:
95 VAC to 265 VAC 1Ph 50/60 Hz
24 AC/DC
Max Temp:
150° F
Valve/Actuator Packages
- Compact: Perfect for OEM and skid manufacturers with a footprint of 2.75” x 4” up to a 2” ball valve
- Multi-voltage: 95 VAC to 265 VAC or 24 VAC/VDC
- Motor: Reversing, brushless DC motor
- Capacitor Discharge System: A capacitor is used in place of batteries for failsafe mode
- Fail Position: Fail close is standard; fail as is, or fail open are options
- Gear Train: Permanently lubricated steel gears
- Corrosion Resistant Enclosure: NEMA 4X enclosure with stainless steel trim
- ISO mounting configuration
- Electrical Connection: NEMA 4X cable gland with two-meter cable
- Position Indication: Highly visible beacon position indicator
- LED Position Indication: RED closed, GREEN open
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Auxiliary Contacts: Open and closed dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC
- Space Heater: Internally wired to limit condensation
- CE Compliant: All actuators are CE labeled and compliant
- 75% Duty Cycle: Extended duty cycle is ideal for high cycling applications
- QR Code: Links to user manual; includes wiring schematic
- Simple Wiring: Wiring technique is the same for all voltage units
- RoHS Compliant
Page Category: Actuators
A failsafe actuator cycles as on/off while charging internal capacitors. When power is lost, the capacitors discharge and power the unit to a predetermined fail position. When power is restored, the capacitors charge up again.
Resources:
Data Sheets
Specifications:
Sizes:
S20FS, S50FS, S110FS, S400FS
Amp Draw:
0.34 Amp for S20, 0.39 Amp for S50, 1.24 Amp for S110, 1.83 Amp for S400
Cycle Time:
Per 90 degrees: 10 seconds
Torque:
177 in-lbs to 3540 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter color-coded cable
Enclosure:
NEMA 4X
Voltage:
95 VAC to 265 VAC 1Ph 50/60 Hz
24 AC/DC
Max Temp:
150° F
Valve/Actuator Packages
- Compact: Perfect for OEM and skid manufacturers
- OLED Screen: Displays valve position and alarms
- Push Buttons: Used to calibrate/adjust end positions and operate local controls
- Multi-voltage: 95 VAC to 265 VAC or 24 VAC/VDC
- Motor: Reversing, brushless DC motor
- Capacitor Discharge System: A capacitor is used in place of batteries for failsafe mode
- Selectable Fail Position: Fail close is standard; fail as is, or fail open are options
- Corrosion Resistant Enclosure: NEMA 4X enclosure with stainless steel trim
- Electrical Connection: NEMA 4X cable gland with two-meter cable length
- LED Position Indication: RED closed, GREEN open, BLUE fault
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Auxiliary Contacts: Open and close dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC
- Alarm Contacts: Dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC for alarm status (over torque, as an example)
- Space Heater: Internally wired to limit condensation
- CE Compliant: All actuators are CE labeled and compliant
- 75% Duty Cycle: Ideal for high cycling applications
- Output Torque: Series 19 electric actuators have an output torque range from 177 in-lbs to 3540 in-lbs
- Simple Wiring: Wiring technique is the same for all voltage units
- Local Controls: Used with OLED and push buttons, a user can locally open or close units via password
- QR Code: Links to user manual; includes wiring schematic
- RoHS Compliant
- Data Sheet – Series 19 Failsafe Actuator
- Data Sheet – Series 19 SAV Failsafe
- Data Sheet – Series 19 SAV Failsafe on Type-21 ball valve
- Data Sheet – Series 19 SAV Failsafe on Type-23 ball valve
- Data Sheet – Series 19 SAV Failsafe on Type-57P butterfly valve
- User Manual | Spanish
- Specification – SAV Failsafe
Sales Resources
Page Category: Actuators
An on/off Series 19 electric actuator provides maintenance- and trouble-free operation in an on/off application.
Resources:
Data Sheets
- Data sheet – Series 19 MAV On/Off Actuator for Diaphragm Valve (24 VAC/VDC)
- Data sheet – Series 19 MAV On/Off Actuator for Diaphragm Valve (95 VAC to 265 VAC)
- Data sheet – Series 19 MAV On/Off Actuator for Gate Valve (95 VAC to 265 VAC)
Ideal Applications Include:
Remote locations, locations with no air supply, colder temperatures, smaller valves, low cost applications
Specifications:
Sizes:
S20, S50
Amp Draw:
0.96 Amp for S20, 1.2 Amp for S50 (24 VAC/VDC)
0.24 Amp for S50 (95 VAC to 265 VAC)
Cycle Time:
Per cycle: 13 to 100 seconds
Torque:
177 in-lbs to 442 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter cable
Enclosure:
NEMA 4X PC/PET enclosure with stainless steel trim
Voltage:
95 VAC to 265 VAC
24 VAC/VDC
Max Temp:
150° F
Valve/Actuator Packages
- Compact: Perfect for OEM and skid manufacturers
- OLED Screen: Displays valve position, alarms (such as an over torque condition)
- Push Buttons: Used to calibrate/adjust end positions, local controls
- Multi-voltage: 95 VAC to 265 VAC or 24 VAC/VDC
- Motor: Reversing, brushless DC motor
- Gear Train: Permanently lubricated steel gears
- Corrosion Resistant Enclosure: NEMA 4X PC/PET enclosure with stainless steel trim
- ISO mounting configuration
- Electrical Connection: NEMA 4X cable gland with two-meter cable
- Visual Position Indication: Flat disc position indicator
- LED Position Indication: RED closed, GREEN open, BLUE fault
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Auxiliary Contacts: Open and closed dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC
- Alarm Contacts: Dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC for alarm status (over torque, as an example)
- QR Code: Links to user manual; includes wiring schematic
- Space Heater: Internally wired to limit condensation
- CE Compliant: All actuators are CE labeled and compliant
- 70% Duty Cycle: Extended duty cycle is ideal for high cycling applications
- Simple Wiring: Wiring technique is the same for all voltage units
- Local Controls: Used with OLED and push buttons, a user can locally open or close units via password
- Data sheet – Series 19 MAV On/Off Actuator for Diaphragm Valve (24 VAC/VDC)
- Data sheet – Series 19 MAV On/Off Actuator for Diaphragm Valve (95 VAC to 265 VAC)
- Data sheet – Series 19 MAV On/Off Actuator for Gate Valve (95 VAC to 265 VAC)
- User Manual | Spanish
- Specification – MAV On/Off
Sales Resources
Page Category: Actuators
The basic Series 19 CAV Com Pack® is a mechanical-type actuator available as an on/off unit. The CAV Com Pack® mounts on Asahi/America’s Type-27 Omni® ball valves, Type-21 ball valves, and Type-23 Multiport™ ball valves to provide smooth operation in a compact and lightweight package. The Com Pack® Series 19 fits Omni® ball valve sizes 3/8” to 2”, Type-21 and Type-23 ball valve sizes 1/2″ – 2″ and has a cycle time of 10 seconds per 90 degrees.
Resources:
Data Sheets
- Data Sheet – Series 19 CAV On/Off on Type-27 Ball Valve
- Data Sheet – Series 19 CAV On/Off on Type-21 and Type-23 Ball Valves
Ideal Applications Include:
Remote locations, locations with no air supply, colder temperatures, smaller valves, low cost applications
Specifications:
Sizes:
C20 for 3/8″ – 2″ Omni® Type-27 ball valves
C20 for 1/2″ – 2″ Type-21 ball valves and Type-23 Multiport™ ball valves
Amp Draw:
0.18 Amp
Cycle Time:
Per 90 degrees: 10 seconds
Torque:
177 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter color-coded cable
Enclosure:
NEMA 4X
Voltage:
95 VAC to 265 VAC 1Ph 50/60 Hz
24 AC/DC
Max Temp:
150° F
Valve/Actuator Packages
- Compact: Compact and lightweight actuated valve package that is ideal for OEMs
- Motor: Reversing, brushless DC motor
- Multi-voltage: 95 VAC to 265 VAC or 24 VAC/VDC
- Gear Train: Permanently lubricated solid gears
- Corrosion Resistant Enclosure: NEMA 4X enclosure with stainless steel trim
- Position Indication: Highly visible dome position indicator
- LED Position Indication: RED closed, GREEN open
- Manual Override: Manually cycle valve via electroless nickel-plated hex key
- Auxiliary Contacts: Open and closed dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC
- Space Heater: A two-watt heater is internally wired to limit condensation
- QR Code: Links to user manual; includes wiring schematic
- RoHS Compliant
Page Category: Actuators
An on/off Series 19 electric actuator provides maintenance- and trouble-free operation in an on/off application.
Resources:
Data Sheets
- Data Sheet – Series 19 SAV On/Off Actuator
- Data Sheet – Series 19 SAV On/Off Actuator on Type-21 ball valve
- Data Sheet – Series 19 SAV On/Off Actuator on Type-23 ball valve
- Data Sheet – Series 19 SAV On/Off Actuator on Type-57P butterfly valve
Ideal Applications Include:
Remote locations, locations with no air supply, colder temperatures, smaller valves, low cost applications
Specifications:
Sizes:
S20, S50, S110, S400
Amp Draw:
0.34 Amp for S20, 0.39 Amp for S50, 1.24 Amp for S110, 1.83 Amp for S400
Cycle Time:
Per 90 degrees: 10 seconds
Torque:
177 in-lbs to 3540 in-lbs
Electrical Connection:
NEMA 4X cable gland with two-meter color-coded cable
Enclosure:
NEMA 4X
Voltage:
95 VAC to 265 VAC 1Ph 50/60 Hz
24 AC/DC
Max Temp:
150° F
Valve/Actuator Packages
- Compact: Perfect for OEM and skid manufacturers
- OLED Screen: Displays valve position, alarms (such as an over torque condition)
- Push Buttons: Used to calibrate/adjust end positions and operate local controls
- Multi-voltage: 95 VAC to 265 VAC or 24 VAC/VDC
- Position Indication: Highly visible beacon position indicator
- LED Position Indication: RED closed, GREEN open, BLUE fault
- Manual Override: Manually cycle valve via electroless nickle-plated hex key
- Auxiliary contacts: Open and closed dry contacts rated 0.1 Amp @ 250 VAC, 0.5 Amp @ 30 VDC
- Space Heater: Internally wired to limit condensation
- QR Code: Links to user manual; includes wiring schematic
- RoHS Compliant
- Data Sheet – Series 19 SAV On/Off Actuator
- Data Sheet – Series 19 SAV On/Off Actuator on Type-21 ball valve
- Data Sheet – Series 19 SAV On/Off Actuator on Type-23 ball valve
- Data Sheet – Series 19 SAV On/Off Actuator on Type-57P butterfly valve
- User Manual – SAV | Spanish
- Specification – SAV On/Off
Sales Resources
Page Category: Actuators
Series 79P stainless steel pneumatic actuators have a 316 stainless steel housing for chemical resistance and high strength. The actuator functions using a double piston rack and pinion arrangement for a smooth torque profile throughout the actuator stroke. Air-to-spring models feature pre-loaded springs that safely avoid potential hazards during maintenance. The base of the actuator has an ISO output drive and bolt circle for easy mounting to quarter turn valves. The top of the actuator has a visual position indicator and a NAMUR mounting pad to accommodate mounting accessories. The air ports are 1/4″ NPT and have a NAMUR bolt pattern to accommodate flush mount solenoids.
Resources:
Datasheet – Series 79 Pneumatic Actuator
Ideal Applications Include:
Chemical Processing, Bleach Plants, Aquariums, Mining, Water Treatment, Landfills, Swimming Pools, Power Plants
Specifications:
Torque:
100 to 3795 in-lbs
Materials:
316 stainless steel housing and stainless steel hardware
Models:
Air-to-air
Air-to-spring (fail closed)
Air-to-spring (fail open)
- Actuator body and end caps constructed of 316 stainless steel
- Double piston, rack and pinion operation
- Female ISO output drive
- 80psi to 120psi recommended operating pressures
- Fail positions can be specified for air-to-spring actuators
- Visual position indicator
- -25° F to 195° F operating temperature range
- 1/4″ NPT air connections
- Safety springs for safe maintenance
- ISO output drive and bolt pattern for easy mounting
- NAMUR accessory mounting
- Output shaft is 316 stainless steel