AUMA SAEx 25.1 Explosion-Proof Multi-Turn Actuator

Overview

AUMA SAEx 25.1 begins the large-frame half of the series as seventh size. Tripping torque is adjustable from 630 to 2,000 Nm (S2-15 min), the flange is F25 and the handwheel measures 400 mm.

The SAEx 25.1 reaches Omani and GCC projects through Seven Star LLC, a trusted AUMA supplier. Engineers in Muscat, Sohar and Salalah deal with one regional contact for quotation, delivery and start-up advice. For comparison, review the SAEx series overview, the Ex modulating range (SAREx) and the AUMA GS part-turn gearboxes.

Operating Principle of the AUMA SAEx 25.1

Inside the SAEx 25.1, a 3-phase AC motor turns a reduction gear and the output drive. Position and torque are monitored mechanically, so a seized valve trips the actuator before the stem is overloaded. Self-locking applies up to 90 rpm at 50 Hz; from 125 rpm it does not, and AMExC or ACExC controls complete the drive.

Engineering Design of the AUMA SAEx 25.1

Handling a 155 to 165 kg actuator needs a hoist and a plan. Check that the F25 flange face, the 95 mm stem bore and the valve yoke are compatible before the actuator leaves the warehouse. Because the documented marking is group IIB, hydrogen or acetylene service (group IIC) is not covered and must be clarified with AUMA before ordering. Choose IP68 as an option where flooding of the valve pit is possible.

The motor is wired in a separate connection compartment, with direct terminal connection for the actuator controls. IP67 is standard, IP68 optional, and the optional heater is rated 12.5 to 25 W.

Key Features of the AUMA SAEx 25.1

Headline data of the SAEx 25.1, as documented by AUMA:

• Adjustable trip torque from 630 to 2,000 Nm for 15-minute duty, 1,400 Nm for 30-minute duty.
• Permitted run torque begins at 700 Nm and ends at 380 Nm for S2-15 min, depending on speed.
• Output speeds of 4–180 rpm (4 and 5.6 rpm on request) at 50 Hz, with up to 40 starts per hour.
• Handwheel diameter 400 mm, approximate weight 155 kg (4–22 rpm), 165 kg (32–180 rpm).
• Motor power of 1.1–15 kW at 400 V, nominal currents of 7.0–30 A.

Selecting the AUMA SAEx 25.1 for Your Valve

The SAEx 25.1 starts the larger frame series with 630 to 2,000 Nm tripping torque, an F25 flange and a 95 mm stem capacity. Two differences from the 16.2 matter at the specification stage: the explosion-protection group is IIB rather than IIC, and standard enclosure protection is IP67 with IP68 as an option. The maximum number of starts per hour falls from 60 to 40. Weights are 155 kg and 165 kg, so a crane or lifting device is needed during installation and replacement.

Compared with the SAEx 16.2, the SAEx 25.1 offers twice the maximum tripping torque, 2,000 Nm against 1,000 Nm, on an F25 flange instead of F16. The next frame, the SAEx 30.1, raises this to 4,000 Nm on F30 with a 500 mm handwheel, at 195 kg and more.

AUMA SAEx 25.1 Torque and Speed Data

The following limits apply to the AUMA SAEx 25.1 at rated voltage and an ambient temperature of +40 °C. Illustrative calculation, not AUMA data: a valve needing 60 turns per stroke takes 450 s at 8 rpm, 113 s at 32 rpm and 29 s at 125 rpm.

Worked Sizing Example for the SAEx 25.1 (Illustrative Calculation)

A large crude-oil export valve needs 1,450 Nm to seat and 450 Nm to run. The SAEx 25.1 supplies 2,000 Nm tripping torque, but run torque is 700 Nm up to 11 rpm, 600 Nm at 16 to 22 rpm and 500 Nm at 32 to 90 rpm. The 450 Nm running demand is met at all of these speeds, while at 125 rpm (400 Nm) it is not. At 30 starts per hour or fewer, the 40-per-hour limit is far from restrictive. This is an illustrative calculation, not AUMA data.

Motor and Electrical Data of the AUMA SAEx 25.1

5 speed points from AUMA’s separate electrical data sheet (S2-15 min, 400 V / 50 Hz), 1.1 to 15 kW; approximate values that are not part of the technical datasheet attached here.

Explosion Protection and Installation Notes for the AUMA SAEx 25.1

Standard ATEX markings of the SAEx 25.1 per AUMA: II 2G Ex db eb IIB T4 or T3 Gb, II 2G Ex h IIB T4 or T3 Gb and II 2D Ex tb IIIC T130 °C or T190 °C Db. Certificate: TÜV 14 ATEX 7542 X. Confirm temperature class and zone on the nameplate.

From this size the certificate changes to TÜV 14 ATEX 7542 X and the gas group to IIB, so projects that need hydrogen or acetylene service must clarify group IIC with AUMA first.

Industrial Applications

The AUMA SAEx 25.1 is chosen for very large gate and globe valves in hazardous areas, for example export-pipeline block valves, large storage-tank isolation valves and heavy process valves in refineries. Group IIB certification covers many hydrocarbon atmospheres, and the IP67 standard enclosure with an IP68 option supports outdoor installation in dusty, humid conditions.

Seven Star LLC supplies the SAEx 25.1 to EPC contractors and operators in Oman who need genuine AUMA large-frame actuators with factory documentation. Because of its 155 to 165 kg weight, we recommend discussing lifting and valve-yoke requirements early in the RFQ stage.

Technical Specifications

Key figures for the AUMA SAEx 25.1, taken from AUMA’s technical data sheet.

Neighbouring sizes and counterparts: AUMA SAEx 16.2 explosion-proof actuator, AUMA SAEx 30.1 explosion-proof actuator, AUMA SAREx 25.1 explosion-proof modulating actuator and AUMA SA 25.1 multi-turn actuator.

Request a Quote for AUMA SAEx 25.1

To request pricing for the AUMA SAEx 25.1, contact the Seven Star LLC instrumentation division. The datasheet is downloadable here, and each unit is supplied with local support.