Electric Actuators for Gate Valves

Electric actuators for gate valves are used to automate the opening and closing of pipeline valves operated by multi-turn movement of the stem. The actuator generates the required torque and provides the rotation needed to move the gate valve between its operating positions.

“ZAVOD “ARMA” LLC represents equipment from the Austrian manufacturer SCHIEBEL ANTRIEBSTECHNIK GMBH in Ukraine. For gate valve automation, SCHIEBEL offers AB and CM series multi-turn electric actuators. The specific model and configuration are selected according to the gate valve design, required torque and axial thrust, mounting parameters, duty and operating conditions.

A correctly selected electric actuator for a gate valve enables local or remote control, monitoring of valve status and integration of the equipment into the automation system of the process facility.

Why a Gate Valve Requires a Multi-Turn Electric Actuator

The design of a gate valve requires the closure element to move between the open and closed positions. To achieve this, the operating mechanism must make the required number of revolutions. This is why a multi-turn electric actuator is used for most standard gate valve automation applications.

Unlike a ball valve or butterfly valve, whose operating movement is normally approximately a quarter turn, a gate valve requires multi-turn movement. The electric actuator rotates the stem and moves the closure element in accordance with the design of the specific gate valve.

Torque is not the only important parameter. For rising-stem gate valves, axial thrust and the design of the actuator output drive must also be taken into account. SCHIEBEL documentation for multi-turn actuators provides suitable mounting interfaces and output drive forms for use with valves of this type.

An electric actuator for a gate valve is therefore not selected solely on the basis of nominal diameter. The mechanical characteristics of the specific valve and its operating requirements must also be considered.

SCHIEBEL Electric Actuator Series for Gate Valves

AB Series Electric Actuators

The SCHIEBEL AB series comprises multi-turn electric actuators for On-Off and Modulating Duty. The manufacturer offers several AB sizes with different torque ratings, allowing technical selection according to the characteristics of the specific gate valve.

AB actuators are provided with valve mounting interfaces in accordance with ISO 5210. The manufacturer’s documentation also specifies output drive forms designed to transmit torque and, in the appropriate version, withstand axial load from the stem.

AB electric actuators can be used with local and remote control. The control system provides actuator status signals, including indication that the open or closed position has been reached.

The specific AB series actuator for a gate valve must be selected using the actual technical data of the valve rather than its type or size alone.

CM Series Electric Actuators

SCHIEBEL also offers CM as a series of multi-turn electric actuators. It is based on a modular concept and can serve as the basis for different configurations depending on the mechanics of the specific valve.

For the CM multi-turn actuator, the manufacturer provides different sizes and valve mounting options. The specific version is selected according to the required torque, stem parameters, duty and other technical characteristics of the gate valve.

SCHIEBEL also uses the CM series in combination with mechanical modules for other types of movement. For a standard gate valve control application, however, the corresponding multi-turn version is considered first.

AB and CM should therefore not be separated according to the simplified principle that one series is for large gate valves and the other for small gate valves. Selection is based on the technical parameters of the specific equipment.

How to Select an Electric Actuator for a Gate Valve

An electric actuator for a gate valve must be selected from the valve’s technical documentation. DN alone is not sufficient because gate valves with the same nominal diameter may have different designs and different actuator requirements.

The required torque is determined first. For a rising-stem gate valve, the axial thrust generated while moving the closure element is also important. The stem diameter and other stem parameters, mounting interface, number of turns for full travel, required speed and duty must also be taken into account.

Power-supply and control-system requirements are defined separately. If remote gate valve control is required, the appropriate actuator configuration and signals for interaction with the automation system must be provided.

It is also important to determine how valve status and gate valve position are to be monitored. The specific set of functions depends on the SCHIEBEL series and selected control system.

These data are used to select the appropriate gate valve electric actuator, its size, output drive form and control configuration.

Gate Valve Control and Automation

Gate valve automation makes it possible to perform opening and closing operations without continuous manual operation directly at the valve. The electric actuator provides mechanical movement in response to a control-system command and allows information about equipment status to be obtained.

SCHIEBEL electric actuators provide local and remote control. Depending on the version, the system can transmit status signals, including information on opening, closing and actuator movement.

A gate valve with an electric actuator can be integrated into the automation system of a process facility. The control method, required signals and communication capabilities are determined when selecting the specific configuration.

Automation therefore covers not only the mechanical movement of the gate valve, but also the interaction of the electric actuator with the plant control system.

When a Gate Valve Requires a Failsafe Solution

Failsafe is not a standard function required for every gate valve. It is used when the process requirements specify that, in the event of a power failure or another defined emergency, the valve must automatically move to a specified safe position.

SCHIEBEL separately offers Failsafe electric actuators for reverse-acting gate valves. This is a special configuration for gate valves of the corresponding design in which the Failsafe function provides the required emergency movement.

Not every gate valve can therefore simply be equipped with Failsafe instead of a standard AB or CM actuator. The valve design and the process safety scenario must first be determined.

If emergency closing is required for a specific assembly, it must be verified that the gate valve design and SCHIEBEL Failsafe configuration correspond to the required direction of emergency action. The same applies to processes in which the safe state is the open position.

Where Gate Valves with Electric Actuators Are Used

Industrial gate valves with electric actuators are used at process facilities where it is necessary to automate control of process-medium flow and integrate pipeline valves into the control system.

Electric automation is particularly relevant where manual operation is inconvenient because of the valve location, where remote execution of commands is required, or where gate valve operation forms part of an automated process.

Each gate valve with an electric actuator should be considered as a specific combination of valve, mechanical actuator and control system. The actuator parameters are therefore determined according to the characteristics of the specific gate valve and the conditions in which the pipeline operates.

Buy an Electric Actuator for a Gate Valve in Ukraine

“ZAVOD “ARMA” LLC supplies SCHIEBEL equipment in Ukraine and provides technical support in selecting electric actuators for industrial valves.

To purchase an electric actuator for a gate valve, the main technical characteristics of the valve must be provided. Correct selection requires information on the gate valve type and design, torque, axial thrust where applicable, stem parameters, mounting interface, number of turns, duty and operating conditions.

Requirements for local and remote control, position indication and integration into the automation system must also be defined.

Based on these data, the appropriate AB or CM series, size, output drive form and control-system configuration are determined. This approach makes it possible to select the actuator according to the actual characteristics of the gate valve rather than nominal diameter alone.

FAQ

How is the required actuator torque determined?

The required torque is determined from the technical characteristics of the specific gate valve and the data provided by its manufacturer. When selecting an actuator, the valve design, stem parameters, duty and axial load, where it is transmitted to the actuator, must also be considered. Actuator torque should therefore not be determined solely from the gate valve DN without the underlying technical data.

Can an electric actuator be installed on an existing gate valve?

In many cases, an existing gate valve can be automated, but compatibility must be checked against the technical documentation. The required torque, axial thrust, stem parameters, type and dimensions of the mounting interface, number of turns and available installation space are taken into account. The appropriate electric actuator and required mechanical connection can then be determined.

What is the difference between AB and CM for gate valve control?

AB and CM are SCHIEBEL multi-turn electric actuator series, but they cover different design and technical ranges. Current AB documentation includes sizes with maximum torque ratings up to 5,000 Nm, while the current CM multi-turn series includes sizes up to 250 Nm. However, the choice between AB and CM cannot be based on maximum torque alone. The actual gate valve torque, stem parameters, mounting interface, speed, duty, control system and other requirements of the specific facility must also be considered.