Valves

In process technology plants, liquids, gases, vapours, and sludge need to pass through pipelines. Industrial valves are used to inhibit or release medium flow as well as to control the resulting flow rate by opening or closing the valves. AUMA actuators are remotely controlled from the control room to operate valves

Automating industrial valves

Modern industrial applications are based on a high level of valve automation. This is the requirement for managing complex processes. The actuator positions the valve in compliance with operation commands issued by the DCS. When reaching end positions or intermediate positions, the actuator stops and signals the status to the control system.

Electric actuators

Electric actuators are equipped with an electric motor/gearbox combination, particularly developed for valve automation, providing the torque required for operating the moving elements of gate or butterfly valves as well as ball and globe valves. Manual valve operation is possible using the handwheel, available as standard. The actuator records travel and torque data from the valve, actuator controls process this data and are responsible for switching the actuator motor on and off. Typically, actuator controls are integrated within the actuator and are equipped with a local control unit apart from the electrical interface to the DCS. The basic requirements for actuators have been specified in the international standard EN 15714-2 since 2009.

Requirement for diversity

Process engineering plants with pipe systems and valve automation are required all around the globe. Not only types of plants and valves are crucial factors for electric actuators but also the climatic conditions in which they are operated. AUMA actuators guarantee reliable and safe service under most extreme environmental conditions.

International test authorities confirm the quality of AUMA actuators designed, manufactured, and tested to customer specifications by issuing product certificates.

As an independent manufacturer, AUMA can look back on long- standing experience and collaboration with the valve industry, plant engineering, and end users within the process applications of the oil & gas industry.

Requirement for reliability

Process engineering plants are only efficient, economic and safe if all components involved provide reliable service during the entire lifetime. Many plants are scheduled for lifetimes of several decades. Consequently, reliable actuator service is expected during all this time. Of course, AUMA can continue to supply spare parts for type ranges which are scheduled to be discontinued for quite a long time period.

The actuation mode is considered a significant distinction factor between the different valve types.

A typical example of multi-turn valves are gate valves. They require a defined number of turns at valve input for a complete valve stroke from CLOSED to OPEN and vice versa.
Butterfly valves or ball valves are typically used if part-turn move- ments up to 90° are required.
Globe valves are normally operated via linear movement. Further- more, certain valves are operated via lever arrangements. In this case, we are talking about lever movement.

Specific types of motion require specific actuator types.

SAEx multi-turn actuators and SQEx part-turn actuators are the core products of the AUMA product portfolio.

AUMA actuators

The basic function of AUMA actuators is the same across all products.

The gearing is driven by an electric motor. The torque applied at the gearing output is transmitted to the valve via a standardised mechanical interface. A control unit within the actuator records travel and monitors torque applied. When reaching a valve end position or a predefined torque limit, the control unit sends a signal to motor controls. Upon receiving this signal, motor controls typically integrated within the actuator stop the actuator. Motor controls are equipped with an appropriate electric interface adapted to the DCS to exchange operation commands and feedback signals between motor controls and DCS.

SAEx multi-turn actuators and SQEx part-turn actuators

Both type ranges are designed on the same principle. Commission- ing and operation are virtually identical.

SAEx multi-turn actuators

In compliance with EN ISO 5210, a multi-turn actuator is capable of withstanding thrust applied to the valve and transmits torque to the valve for at least one revolution. In general, multi-turn actuators are required to perform more than one revolution. Gate valves are often equipped with rising valve stems. They are operated on the basis of several revolutions performed by the multi-turn actuator. Therefore, SAEx multi-turn actuators are equipped with a hollow shaft which housesthegatevalvestemfortheseapplications.

SQEx part-turn actuators

In compliance with EN ISO 5211, part-turn actuators transmit torque to the valve for a rotation of one revolution or less. They do not have to be capable of withstanding axial thrust.

Part-turn valves – such as butterfly valves and ball valves – are often designed without end stop. SQEx part-turn actuators are equipped with internal end stops to allow precise approaching of end positions during handwheel operation.

SAEx multi-turn actuators with mounted gearbox

The application range is considerably increased by mounting AUMA gearboxes to SAEx multi-turn actuators.

> The combination with LE linear thrust unit acts as linear actuator. > The combination with GF lever gearbox acts as lever actuator.
> In particular when requiring higher torques, we obtain a part-turn actuator when combining with GS gearbox.
> Amulti-turn actuator with higher outputt or queis obtained when combining with GST or GK multi-turn gearboxes. Apart from this, solutions for special valve types or installations can be implemented.