Classification of electrical actuators

An electrical actuator is a device that converts the output signal of a regulator using electrical energy to produce mechanical movement.

Electric actuator

Pay attention to the theory of automatic control and control devices.

Electric actuators are used in cases where little effort is required to move the regulating body or, conversely, a large force is required. One of the advantages of using electric actuators is ease of installation. All industrial enterprises are provided with electricity, and installation work on installing electrical actuators is usually not a problem.

There are two general types of electrical actuators: solenoid actuators and electrical motor actuators.

Electrical solenoid actuators

Solenoid actuators use the principle of electromagnetic attraction to produce mechanical movement.

Solenoid actuator

The main advantage of solenoid actuators is their fast response: armature movement is almost instantaneous after current is applied or turned off. The disadvantage of solenoid actuators is that they cannot be set between extremes: they are either fully extended or fully compressed (rod retracted). Also, the design of the solenoid actuator prohibits its use in components that require large forces. To generate large gravitational forces, the solenoid actuator must be extremely large in size.

Main details:

1. An anchor, like a cylinder of iron or steel; 2. rod that connects the armature to the controlled device; 3. a spring that presses on the anchor; 4. electrical winding, which is a coil of wire with leads.

Operating principle of the solenoid mechanism:

1. Current passes through the winding, the coil becomes an electromagnet; 2. the armature is attracted by the electromagnet and moves inside the coil; 3. As a result, the rod moves, causing a change in the position of the device associated with it; 4. When the electric current is turned off, the armature returns to its original position by a spring.

Hydraulic modifications

Hydraulic devices are well suited for adjusting valves. If you believe the opinion of experts, there are many modifications of contact rheostats on the market. The main disadvantage is the reduced frequency. In this case, contactors are used only for two phases. Some modifications are made with blockers. Expanders for them are selected of a two-pole type. The conductivity parameter reaches a maximum of 130 microns. These modifications are not best suited for powerful drive devices. You can buy a good actuator in a store for 33 thousand rubles.

Electric motor actuator

Electric motor actuators are typically used when a large amount of force is required to produce mechanical movement and positioning between extreme positions is required.

Electric motor actuator

Operating principle of electric motor actuator

1. An electric motor drives the gear train, which is used to move the regulator; 2. two position switches (labeled A and B) are located at the points at which the control element is fully open and fully closed; 3. When the control element reaches the full open position, position switch A opens, turning off the electric motor; 4. Similarly, position switch B opens when the control element reaches the fully closed position, also switching off the motor.

Price list for MEO executive mechanisms, regulating devices, blocks and control devices

The price list below shows wholesale prices* for single-turn electric actuating mechanisms MEO and flange MEOF, as well as regulating devices, control devices, units (PBR, RP4, BSPT, BP, RZD, BRU, IPU, ZU, BU, DUP-M etc., see table-3) and spare parts (see table-4). Prices are indicated for general industrial versions of MEO instruments and actuators (prices for explosion-proof Ex-IIBT4 and nuclear power plant versions are available on request) as of January 2022. All prices are for the basic version - general industrial, excluding the cost of additional options, units and equipment, packaging, shipping and/or delivery costs, excluding tax (VAT = 18%), based on a wholesale order (for large wholesale quantities and for project orders, the price is formed individually, based on the volume of the batch, the agreements reached and the address of the object). Terms of discounts, availability of promotions and special offers and prices - check with managers.

Table-2 (2 of 4): Price list for high-power actuators MEO-250, -630, -1600, -10000, MEOF (flange) (prices of electric drives are indicated as of January 2022)

type of sensor (designation of the position signaling unit (BSP) of the output shaft): - "I" - inductive (BSPI unit), - "P" - rheostat (BSPR, BSPR-IIBT6 (explosion-proof) units), - "U" - current (units BSPT, BSPT-IIVT6 (explosion-proof), - “M” - limit switch block (BKV, BSPM-11VT6 (explosion-proof)).

Table-3 (3 of 3): Price list for regulating devices and control devices and units (PBR, RP4, BSPT, BP, RZD, BRU, IPU, ZU, BU, DUP-M, etc., prices are indicated according to condition as of January 2018)

Table-4 (4 of 3): Price list for spare parts and accessories (SP&A) (prices are as of January 2018)

The above price list shows wholesale prices* for single-turn electric actuating mechanisms MEO (lever) and flange MEOF, as well as regulating devices, control devices, units (PBR, RP4, BSPT, BP, RZD, BRU, IPU, ZU, BU, DUP-M, etc.) and spare parts. Prices are indicated for general industrial versions of MEO instruments and actuators (prices for explosion-proof Ex-IIBT4 and versions for nuclear power plants are available on request) as of January 2022. Only basic versions of MEO are available at the production warehouse; the production time for other mechanisms is from 15 working days (subject to the availability of all components). All prices are for the basic version excluding tax (VAT=18%), additional costs. options and equipment, packaging, shipping and/or delivery costs, based on a wholesale order (for large wholesale quantities and for project orders, the price is formed individually, based on the volume of the batch, agreements reached and the address of the facility). Terms of discounts, availability of promotions and special offers and prices - check with managers.

Technical description (characteristics) of actuators MEO, MEOF

Single-turn (or part-turn) electric actuators MEO (lever), MEOF (flange) and PEOZ drives are designed to transmit torque to the valve when it is rotated one turn or less (from 0 to 360°).

Electrical actuators MEO and MEOF (electric drives) are designed to actuate shut-off and control valves in automatic process control systems, in accordance with command signals from regulating and control devices.

PEOZ actuators are designed to operate shut-off valves in the “Open-Close” mode.

Options for actuators and drives:

- general industrial (basic version) - explosion-proof (explosion hazard category for explosion-proof versions (subgroup and temperature class) - IIBT4); — for nuclear power plants (increased reliability for nuclear power plants and nuclear energy facilities (UAE)).

Functions of the executive mechanisms of MEO and MEOF

— Automatic, remote or local (manual) opening and closing of valves, stopping of valves in any intermediate position; — Indication of the degree of opening (closing) of the valve on the scale of the local indicator; — Positioning of the working element of the reinforcement in any intermediate position; — Formation of a discrete signal about the intermediate and final positions of the working body of the valve; — Torque overload protection (MEO(F)-1600-04K, -08K, -09K, MEOF-10(K)). Modern modifications of actuators also allow the implementation of a digital output option via the RS485 interface: - Generation of digital signals of the state of limit and limit switches for transmission via the RS-485 interface (mechanisms equipped with a sensor unit BD-1, BD-2). — Discrete state of opening and closing torque switches for transmission via RS-485 interface (MEO(F)-08K, -09K, MEOF-10(K)) — Generation of digital signals of the state of opening and closing torque switches, torque signal for transmission via RS-485 interface (MEO(F)-08K, -09K, MEOF-10(K)).

Functions of PEOZ and KSATO drives operating in automatic control systems:

Functions of KSATO drives operating in the “Open-Close” mode: Remote or manual opening and closing of valves; Remote stop of valves in any intermediate position; Indication of the degree of opening (closing) of the valve on the scale of the local indicator; Torque overload protection.

Parameters of the PR-5 model

This is an inexpensive and high-quality mechanism. It is ideal for low power drives. Its overload percentage is extremely low. The conductivity parameter in the device is maintained at 120 microns. In this case, the frequency fluctuates around 44 Hz. Many experts say that the coil is not afraid of large overloads. However, the expander burns out quite often. There is no lock in the standard configuration of the mechanism. The motor for the model is selected with a power of 4 kW. The switch is a limit switch and operates very smoothly. The price for this mechanism starts from 44 thousand rubles.

IM-41 series device

The presented mechanism is classified as a pneumatic device. In production, the modification is found in plunger devices. According to experts, the coil is used of a low-voltage type, and the overload indicator fluctuates around 40 A.

It is also worth noting that the modification uses a blocker that works without failures and is equipped with a KK30 class protection system. The motorized valve is fixed to the contactors. The motor for the device is selected at 3 kW. There is no anchor in this case. The failure rate is around 0.4%. Some experts say that the modification quickly overheats. However, it is important to note that the maximum operating temperature of the mechanism is 45 degrees. The output shaft is applied at 3.2 cm.

In total, the model has three contactors, which are installed behind the output shaft. This mechanism does not have a modulator. The device is not best suited for ventilation systems. The closure coefficient is on average 34%. The user can purchase this mechanism at a price of at least 40 thousand rubles.

PR-1M series device

This actuator copes well with controlling drive devices. His coil is capable of withstanding large overloads. It is also worth noting that the modification is equipped with a three-pole expander. The model has a rheostat with a sensor.

The blocker in the PR-1M deserves special attention. The failure rate of the model is only 0.2%. The output shaft starts very smoothly and has extremely low wear. The expander of the modification is installed behind the contactor. The model is suitable for adjusting pumps. Pipeline parts may be matched with compressors. The price for this mechanism fluctuates around 40 thousand rubles.

Features of the PR-2 modification

This mechanism is quite often used in ventilation systems. The input shaft is used with a small diameter. It is also worth noting that the modification is distinguished by a high-quality rheostat, which is capable of maintaining a frequency of 55 Hz. The model's motor is 5 kW. The expander in this case is of a three-pole type, and its protection is applied to the KK50 series. In total, the model has three contactors.

The modification is well suited for low-power drive systems. The coil is used at 40 W. There is no modulator included as standard. The closure rate is within 33%. The blocker of the modification is used with an adapter. The user can purchase the mechanism of the presented series at a price of 30 thousand rubles.

Parameters of the MEO-23 model

This automatic control system is distinguished by its high output impedance. The device is well suited for drive modifications. The coil of the model is designed for 14 W. Protection class KK40 is used. It is also worth noting that the rheostat is a wired type. The softness of movement in this case is ensured by the expander. According to experts, engine failures occur infrequently. The model does not have a blocker.

The pressure reduction rate is at the level of 55%. In this case, the sensor is not provided by the manufacturer. The modification is great for cranes. The standard motor is 4 kW. The operating frequency of the mechanism is maintained at 55 Hz. The switch in the device is of the limit type. This automatic control system costs approximately 35 thousand rubles.