AUMA SARVEx Explosion-Proof Variable-Speed Modulating Actuator

Overview

AUMA SARVEx multi-turn actuators combine explosion protection with variable-speed modulating control. They are rated for class C modulating duty (S4 – 25 %, S4 – 50 % as an option), paired with ACVExC 01.2 controls, and extend the AUMA SAREx range with a speed control ratio of 1:10. Sizes SARVEx 07.2 to SARVEx 16.2 deliver 15 Nm to 1,000 Nm tripping torque. The explosion-proof design lets plant engineers use accurate, slow-approach positioning on control valves located in gas or dust hazardous areas.

In Oman and the GCC, Seven Star LLC proudly supplies the AUMA SARVEx for hazardous-area control valves throughout the Sultanate of Oman and the GCC. Our Muscat instrumentation division advises on temperature class, certification and controls, and provides genuine AUMA equipment with documentation.

Modulating Principle and Explosion Protection of the AUMA SARVEx

The AUMA SARVEx reduces the operating speed continuously as it approaches the setpoint, reaching a standstill at the target. This allows a more precise approach than the sudden tripping of a fixed-speed actuator and AUMA describes the ability as particularly crucial for the SARVEx modulating model; positioning accuracy is better than 0.2 %. The speed can also be set by an external controller: the speed setpoint from the DCS may be sent to the ACVExC as a digital signal over fieldbus (0–100 %) or as an analogue 4–20 mA signal, turning speed into a control-loop variable.

The explosion protection follows the SAVEx family. Qualified under ATEX with certificate DEKRA 11 ATEX 0008 X and under IECEx, standard marking is II 2G Ex db eb IIC T4 or T3 Gb for gas atmospheres and II 2D Ex tb IIIC T130 °C or T190 °C Db for dust, with an Ex db IIC option. T4 is available up to +40 °C ambient and T3 up to +60 °C. The permitted number of starts per hour depends on size and speed range and is lower than for the non-Ex SARV; the data sheet gives the figures.

Engineering Design of the AUMA SARVEx

The AUMA SARVEx uses the flameproof AUMA SAREx .2 housing with a 3-phase AC motor and thermoswitches, limit and torque sensing, a handwheel, and the AUMA Ex plug/socket connector (KT) with screw-type motor terminals as standard, and a version with terminal blocks (KES) optional. It is IP68 with double-sealed terminal compartment, KS corrosion protection (KX and KX-G optional) and a sound level below 72 dB(A). Position feedback is available as potentiometer or 0/4–20 mA electronic position transmitter, and non-intrusive settings can be made via the magnetic limit and torque transmitter.

The attachment to the valve follows EN ISO 5210 with flanges F07 to F16 and DIN 3210 options. Speeds at 50 Hz are 6–60, 12–108 and 24–216 rpm, and the SARVEx 16.2 is offered at 6–60 rpm. Sizing at 100 % nominal voltage and +40 °C is based on S4 – 25 %, with S4 – 50 % using lower modulating torque but the same size.

Key Features

The AUMA SARVEx provides the following advantages in hazardous areas:

• ATEX and IECEx qualification permits modulating control with variable speed where explosive atmospheres may occur.
• Speed reduction on approach to the target gives precise settling and less hunting than a fixed-speed explosion-proof actuator.
• An external speed setpoint over fieldbus or 4–20 mA lets the DCS optimise speed as part of the control strategy.
• Multiport valve operation positions up to 16 ports with high precision on manifold valves and sampling bypass duties.
• Speed profiles with up to ten travel sections and soft start and stop limit pressure surges and mechanical shock.
• EMERGENCY and failure operations can use a predefined speed, while soft start and stop remain effective.
• The frequency converter permits 1-phase supply with a 3-phase motor and compensates mains variations.
• Fieldbus control, data logging, process controller (PID) and Bluetooth are provided by the ACVExC 01.2 controls.

Industrial Applications

The AUMA SARVEx serves hazardous-area control valves in oil and gas production, refining and petrochemicals. Typical tasks include multiport valves on production manifolds that divert a flow to a bypass for sampling, four-way valves used to fill coke drums, flow-control valves on gas conditioning skids and pressure or level regulation in chemical plants. In Oman such requirements arise at inland upstream facilities, at the Sohar, Duqm and Salalah industrial zones and on refinery and LNG-related utilities.

In Oman and the GCC, Seven Star LLC supplies the AUMA SARVEx with ACVExC 01.2 controls, and prepares quotations that state the Ex marking and temperature class. For fixed-speed hazardous-area modulating duty, the AUMA SAREx is the standard alternative, and for on-off and positioning duty with variable speed we offer the AUMA SAVEx. Send us your zone classification, gas group and loop requirements for a recommendation. In explosion-proof modulating loops the AUMA SARVEx removes the need to compromise between response time and valve protection, and the AUMA SARVEx can be tuned on site to the actual process dynamics rather than to a worst-case assumption. When reviewing the AUMA SARVEx against the rest of the AUMA range, engineers often also look at the AUMA SARV, the AUMA SAVEx and the AUMA SAREx modulating actuator.

Technical Specifications

The table summarises the AUMA SARVEx as published by AUMA. The data sheet is the binding reference.

Duty S4 – 25 % by size

Valve attachment, handwheel and weight by size

Request a Quote for AUMA SARVEx

To obtain a quotation for the AUMA SARVEx, send a formal RFQ to the Seven Star LLC instrumentation division with area classification, temperature class, valve torque and control signal. We can advise on regional availability and provide the technical datasheet for download from this page. In Oman and the GCC, Seven Star LLC delivers genuine explosion-proof actuators with certificates, warranty and local support.