Valve Electric Actuator Models: DZW / DQW / 2SA / 2SQ / 2SDQ / 2SB / SDQ / XZA / SMC / QT / QB / 903 / 802 / ZB / ZC / QB / DQ / SND / PSL A valve electric actuator is an automated device that uses an electric motor as its power source, converting electrical energy into mechanical energy through a transmission mechanism to drive valves for opening, closing, or regulation. It is one of the key devices for achieving automation in industrial process control.It mainly consists of an electric motor, a reduction mechanism (such as gears or worm gears), a stroke control mechanism, a torque limiting mechanism, and a manual/electric switching mechanism. The electric motor provides rotational power, which is reduced in speed and increased in torque through the reduction mechanism, and then drives the valve stem to rotate (quarter-turn) or lift (linear-stroke) via the output shaft.By motion type:Quarter-turn electric actuators: Rotation 0-360°, suitable for ball valves, butterfly valves, plug valves, etc.Linear-stroke electric actuators: Linear motion, suitable for gate valves, globe valves, control valves, etc.By control mode:On/off type: Fully open or fully closed only.Modulating type: Receives 4-20mA signals for continuous proportional regulation.Compared with pneumatic or hydraulic actuators, electric actuators are easier to power, require no complex air supply piping, offer high control precision, and are easy to integrate with DCS/PLC systems. Modern products also integrate intelligent control modules with features such as overload protection, fault self-diagnostics, and bus communication.The valve electric actuators produced by Kaivex Valve Group are widely used in industries such as water treatment, electric power, petrochemicals, HVAC, and metallurgy. Selection must be based on valve type, torque requirements, stroke time, ingress protection/explosion-proof rating, and control requirements.

Valve Pneumatic Actuator Models: AW / GT / AT A valve pneumatic actuator is a control device that uses compressed air as its power source to drive valve opening, closing, or regulation through a cylinder. It uses air as the working medium, converting pressure energy into mechanical energy, outputting linear displacement or angular displacement to drive the corresponding type of valve. It mainly consists of a cylinder, piston (or diaphragm), spring (for single-action return), end caps, and stroke limiting mechanism, etc.By output motion type:Quarter-turn: Drives ball valves, butterfly valves, plug valves.Linear-stroke: Drives globe valves, gate valves, control valves.By action mode:Double-acting: Air-to-open, air-to-close.Single-acting (spring return): Air-to-open, spring-to-close, or vice versa — automatically returns to a safe position upon air failure.Technical characteristics of pneumatic actuators:Fast action speed with high response frequency; switching time is typically 0.1 to 0.5 seconds.Simple structure, small size, high power output per unit volume.Fire-proof and explosion-proof, intrinsically safe — especially suitable for flammable and explosive environments such as petrochemical plants and coal mines.However, they require an air compressor and air purification system, creating dependence on an air supply.Key selection considerations:Output torque/thrust must meet the valve's opening/closing requirements.Single-acting or double-acting mode must match the process safety failure position.Additional factors to confirm: air supply pressure (typically 0.4–0.7 MPa), ambient temperature, explosion-proof and ingress protection rating (explosion-proof types are flameproof or intrinsically safe designs), and the configuration of accessories such as solenoid valves, limit switches, and positioners.

Gearbox (Worm Gear) Models: AB / D / SB-V / RK / 2CK / KB A valve gearbox (also known as a valve reduction gearbox, gear operator, or worm gear) is a mechanical device that converts high-speed, low-torque input into low-speed, high-torque output through a gear transmission mechanism. It is primarily used to assist in valve operation under manual or powered drive.The core function of a gearbox (worm gear) is to increase output torque, allowing an operator to easily open or close large-diameter or high-pressure valves that require high torque with relatively low handwheel force. At the same time, through the design of the transmission ratio, the gearbox enables slow and smooth valve movement, avoiding impact damage to the sealing surfaces.Internally, it typically uses a worm gear or spiral bevel gear transmission pair.The worm gear mechanism has a self-locking characteristic (i.e., when the input side stops, the output side cannot be driven in reverse) and is widely used on gate valves, globe valves, butterfly valves, and ball valves.Spiral bevel gears offer higher efficiency and no self-locking, making them suitable for valves that require fast opening and closing.Installation types:Top-mounted: Directly connected to the valve stem.Side-mounted: Offset output to accommodate space constraints.The valve gearboxes produced by Kaivex Valve Group are widely used on large-diameter or high-pressure valves in industries such as petroleum, chemical, electric power, and water treatment. When selecting a gearbox, it is necessary to confirm the valve's torque requirements, transmission ratio, handwheel operating force, and ingress protection rating (e.g., IP65). Some high-end models can be connected to electric or pneumatic actuators for manual/automatic integrated switching.

Valve Positioner Models: ZPQ / ZPD-2000/1000 / DVC6200 / DVC2000 / 3800SA / EL100 / EL200 / SIPART PS2 / SITRANS VP300 / SIPART SP2 / AVP100 / AVP102 / AVP300 / AVP301 A valve positioner is a key accessory for pneumatic control valves. Its core function is to improve the control accuracy and response speed of the valve. It operates on a closed-loop control principle, comparing the actual position of the valve stem with the control signal, and accordingly adjusts the air pressure supplied to the actuator.The valve positioner receives a standard electrical signal (such as 4-20mA) or pneumatic signal (such as 0.02-0.1 MPa) from the control system, while simultaneously monitoring the valve opening in real time through a feedback lever. When a deviation exists between the two, the nozzle-flapper mechanism or electro-pneumatic converter inside the positioner regulates the output air pressure, driving the actuator until the valve reaches the commanded position.The main functions of a valve positioner are:Overcoming stem friction and medium unbalanced forces, eliminating valve dead bandAchieving split-range control and flow characteristic correctionAdapting to air-to-open or air-to-close actuators by switching between direct and reverse actionBased on explosion-proof requirements, positioners can be classified as intrinsically safe (Ex ia) or flameproof (Ex d) types.In installation and application, the positioner significantly improves both the dynamic and static accuracy of the control valve, making it suitable for applications with high control quality requirements. When selecting a positioner, it is necessary to confirm the input signal, air supply pressure, action mode, and whether communication protocols such as HART are supported.

Actuator Accessory Models: ZPQ / ZPB201 / PL In a pneumatic valve control system, accessories such as the pneumatic air treatment unit (air triplet), solenoid valve, and limit switch each play an indispensable role, collectively ensuring system stability and controllability.Pneumatic Air Treatment Unit (Air Triplet): This is an air source processing unit, typically consisting of an air filter (removes impurities and moisture), a pressure reducing valve (stabilizes and regulates air pressure), and a lubricator (provides lubrication for pneumatic components). Its purpose is to supply clean, dry, stable-pressure, and lubricated air to downstream equipment.Solenoid Valve: This is the control core of the system. It receives electrical signals to switch the flow path of compressed air, thereby controlling the direction of the pneumatic actuator's action (e.g., valve open or close). A common single-coil 5/2-way solenoid valve is suitable for single-acting actuators, while a double-coil 5/2-way solenoid valve is used for double-acting actuators.Limit Switch (Position Feedback Unit): This is a valve position detection and feedback device. It is mechanically connected to the valve stem or actuator shaft. Through internal micro switches or proximity sensors, it converts the fully open and fully closed positions of the valve into electrical signals, which are transmitted remotely to the control room for status monitoring and interlock control.These three components are typically used together with a pneumatic actuator to form a complete valve control and feedback loop, and are widely used in automated production lines in industries such as petroleum, chemical, and water treatment.