Air Torque DRSC00060U A-Version Pneumatic Rack and Pinion Actuator

Overview

The Air Torque DRSC00060U is a compact aluminium rack and pinion pneumatic actuator from the Air Torque Edition 2010 (4th Generation Upgrade) range, supplied here in the A-Version coating for general industrial service. One body covers two functions: built as type DR it is double acting and delivers 70 Nm at 6 bar, and fitted with spring cartridges as type SC it becomes a spring return, fail-safe actuator giving 42 Nm at the 90° spring position and 27 Nm at 0°. That torque band makes the Air Torque DRSC00060U a natural size for automating small and medium quarter-turn ball valves, butterfly valves and plug valves.

Seven Star LLC supplies the Air Torque DRSC00060U to valve automation workshops, EPC contractors and plant maintenance teams in Oman and the GCC, with engineering support in Muscat. We help customers in Muscat, Sohar, Duqm and Salalah select between double acting and spring return builds, confirm the ISO 5211 interface and drive square against the valve, and combine the actuator with NAMUR solenoid valves and limit switch boxes into complete packages.

Operating Principle

Inside the Air Torque DRSC00060U, two opposed pistons carry gear racks that engage a central pinion. In the double acting DR version, air supplied to port 2 while port 4 is vented drives both pistons outward and rotates the shaft one way; reversing the supply moves the pistons back to the centre and rotates the shaft the other way. Output torque is the piston force from the supply pressure multiplied by the pinion pitch radius, less friction, so a DR actuator gives a linear torque through the full stroke in both directions.

In the single acting SC version, air at port 2 drives the pistons outward and compresses the springs; when air or power is lost, the springs return the pistons and turn the valve to its fail position, which can be configured as fail close or fail open. Spring return torque therefore varies with stroke position, which is why Air Torque quotes two spring values for the DRSC00060U – 42 Nm at 90° and 27 Nm at 0°. For the Air Torque DRSC00060U, valve sizing should compare the valve breakaway and seating torque against the lowest of the relevant air and spring values with a suitable safety factor.

Engineering Design of the Air Torque DRSC00060U

The A-Version body of the Air Torque DRSC00060U is extruded aluminium with an ALODUR anodized coating inside and out, and the manufacturer states that the internal surface roughness has been reduced by around 40% compared with normal hard anodizing, lowering friction and extending seal life. The end caps are pressure die-cast aluminium, anodized and then covered with a light grey RAL 9007 polyester layer; the pistons are die-cast aluminium, anodized black; and the drive shaft is steel with an electroless nickel coating. Fasteners on the end caps and stop screws are A2-70 stainless steel.

The Air Torque DRSC00060U follows EN ISO 5211 with an F05/F07 double flange and a 14 mm female square (DS14), and its G 1/8 inch air connections follow the NAMUR interface of VDI/VDE 3845, so a solenoid valve can be bolted directly to the side face. The top of the shaft and the accessory attachment (AA1) accept limit switch boxes and positioners. External travel stops allow the close position to be adjusted from -5° to +15° and the open position from +75° to +95°. The drive shaft is held by top and bottom bearings and is blowout proof, and each actuator passes a serial tightness and torque inspection before receiving its serial number.

Key Features

Engineers choose the Air Torque DRSC00060U for the following reasons:

• Air Torque DRSC00060U double acting torque of 70 Nm at 6 bar, with spring return values of 42 Nm (spring at 90°) and 27 Nm (spring at 0°).
• Conversion from double acting to spring return by fitting maintenance-free spring cartridges, reducing the number of stocked variants.
• ISO 5211 F05/F07 flange with DS14 square and NAMUR VDI/VDE 3845 accessory interfaces for direct mounting.
• Triple piston guidance that keeps output torque constant under high side load.
• ALODUR-anodized body with polyester-coated end caps, salt spray and Kesternich tested according to the A-Version datasheet.
• Temperature versions for -40 to +80 °C (standard), -15 to +150 °C (high temperature) and -55 to +80 °C (low temperature).
• Working pressure from 2.5 to 8 bar on dry or lubricated air or inert gas, silicone-free construction.
• External OPEN and CLOSE travel stop adjustment over 20° for precise valve alignment.

Industrial Applications

With its 70 Nm double acting output, the Air Torque DRSC00060U is typically mounted on small-bore ball valves for chemical dosing, water treatment and RO pretreatment skids, on wafer butterfly valves in HVAC and district cooling plants, and on drain and sampling valves in oil and gas facilities. Spring return SC builds of the Air Torque DRSC00060U are used where a valve must go to a defined safe position on loss of air, for example on tank inlet isolation or utility shutoff duty in plants in the Sohar and Duqm industrial areas.

The A-Version coating is intended for general industry and is not recommended for sodium hydroxide or strong acids and bases, so Seven Star LLC can advise on stainless steel or other coating versions where the environment is aggressive. For complete valve automation packages we combine the Air Torque DRSC00060U with pilot valves such as the ASCO 551 NAMUR solenoid valve, and for larger torques customers can compare the Rotork CP compact pneumatic actuator or the Masoneilan 96/97 rack-and-pinion actuators that we also supply.

Technical Specifications

Data for the Air Torque DRSC00060U are taken from the Air Torque product page, the Edition 2010 A-Version datasheet and the 4th Generation Upgrade operating manual:

How to Order

Send Seven Star LLC a formal RFQ for the Air Torque DRSC00060U stating DR or SC, spring set, fail direction, temperature version and the valve flange and stem details, and our instrumentation division will confirm the configuration and quote supply on request. The A-Version datasheet and the operating manual are attached on this page for download. Seven Star LLC supplies Air Torque pneumatic actuators and complete valve automation assemblies throughout Oman and the GCC, with engineering support in Muscat.