AUMA SAR 16.2 Modulating Multi-Turn Actuator

Overview

AUMA SAR 16.2 is an AUMA NORM multi-turn actuator for modulating duty (class C, ISO 22153) with a tripping-torque window of 500 to 1,000 Nm and 10 output speeds from 4 to 90 rpm. SAR 16.2 is the largest of the SAR 07.2 to SAR 16.2 group, with 500 to 1,000 Nm of tripping torque and up to 400 Nm of modulating torque at S4-25 percent, an F16 flange, a 77 mm stem bore and a 500 mm handwheel.

Seven Star LLC supplies AUMA products across Oman and the GCC, and supplies the SAR 16.2 with local technical support from Muscat.

Operating Principle

Positioning pulses of at least 100 ms from an AM or AC positioner drive the SAR 16.2, and self-locking holds the valve. Modulating torque runs from 400 Nm at 4 to 11 rpm down to 200 Nm at 63 to 90 rpm, while starts fall from 900 to 200 per hour.

Engineering Design of the AUMA SAR 16.2

Modulating torque is 400 Nm (S4-25 percent) and 280 Nm (S4-50 percent) at the lower speeds, falling to 200 Nm and 175 Nm at the highest speeds. A moderate output speed typically gives the best balance of positioning resolution and torque.

Key Features

What stands out on the SAR 16.2:

• Modulating multi-turn actuator for large control valves.
• The tripping torque can be set anywhere between 500 and 1,000 Nm, an adjustment span of 2.0 to 1.
• The S4 – 50 percent rating of 710 Nm equals 71 percent of the maximum tripping torque.
• Maximum torque per kilogram of mass is about 12.0 to 14.9 Nm/kg.
• An illustrative stroke of 45 turns takes about 123 seconds at 22 rpm.
• It sits above the SAR 14.6 and below the SAR 25.1 in torque class.
• AUMA publishes dimension and electrical data sheets for this size separately.

Selecting the AUMA SAR 16.2

The SAR 16.2 carries weight and modulating capability that the smaller sizes do not offer: 67 kg at low speeds, 79 kg at mid speeds and 83 kg at 63 and 90 rpm. Starts per hour are limited to 900 at the lowest speeds, falling through 600 and 300 to 200 per hour at the highest speeds, and a minimum pulse of 100 ms is specified, with reversal pulses of 110 to 300 ms. These longer pulses mean the AUMA SAR 16.2 suits slower, heavier control duties rather than rapid loop control.

Typical partners are large control gate valves, heavy globe and angle control valves, large water-flow regulating valves and rising-stem sluice gates used for level and flow control.

For large regulating gates and control valves the dead time of the actuator matters as much as its speed. The AUMA SAR 16.2 needs 300 ms at 4 rpm and 110 ms at 90 rpm to start moving after reversal, and the controller should not issue commands more often than this reversal dead time allows. With 900 starts per hour at the lowest speeds the actuator can follow a loop that updates every four seconds or slower, which fits flow, level and pressure loops in water and cooling systems but not fast pressure control. Confirm during commissioning that the end-position limit switches and the torque switches are set in the correct order, so that a modulating valve operating near its end of travel is stopped by limit switching and not by an unintended torque trip.

Sizing example for the AUMA SAR 16.2

Take an illustrative regulating gate that needs 380 Nm running torque and 800 Nm at the seat. The running torque is below the 400 Nm modulating limit (S4-25 percent) at the lower speeds, and the seat torque lies within the 500 to 1,000 Nm window of the AUMA SAR 16.2. The limit falls to 350 Nm at 16 to 32 rpm and to 200 Nm at 63 to 90 rpm, so only speeds up to 11 rpm cover the 380 Nm running torque. A 40-turn stroke at 11 rpm takes about 218 seconds, and 1 percent of that stroke takes about 2 seconds, which is well matched to the 100 ms minimum pulse. These numbers are an illustrative calculation and not AUMA data.

Installation and Mounting of the AUMA SAR 16.2

The 67 to 83 kg mass of the AUMA SAR 16.2 demands a hoist, and the valve yoke or gate frame must carry the weight and the reaction torque. The F16 flange takes stems up to 77 mm and the 500 mm handwheel needs a wide swing radius. Because modulating duty puts continuous load on the gearing, specify lubrication points and access for later maintenance when planning the installation.

Industrial Applications

In Oman the AUMA SAR 16.2 is used for large-flow control at seawater intake and outfall structures, bulk-water flow regulation at transmission network control stations, and level-control gates at wastewater treatment plants. Industrial users in Sohar and Duqm apply it on large condensate and cooling-water control valves.

Next to the SAR 16.2, our genuine AUMA range includes the AUMA SAR 14.1 multi-turn actuator, the AUMA MATIC AM/AC integral actuator controls and the AUMA SAREx explosion-proof modulating actuator.

Neighbouring sizes and counterparts: AUMA SAR 14.6 modulating actuator and AUMA SA 16.2 multi-turn actuator.

Technical Specifications

Data of the AUMA SAR 16.2 from the AUMA technical data sheet for 3-phase AC motors.

Setpoint guide for the SAR 16.2 (illustrative calculation, not AUMA data)

Stroking time for 45 turns at the SAR 16.2 (illustrative calculation, not AUMA data)

Request a Quote for AUMA SAR 16.2

Send Seven Star LLC your valve data, supply voltage and controls to receive a quotation for the AUMA SAR 16.2, and open the AUMA datasheet from this page.