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Actuators Type A

Actuators Type A

Actuators Type A

Product catalog summary
Overview: This document outlines the specifications and guidelines for SOMAS pneumatic actuators, specifically the Type A series, which includes double acting (DA) and single acting (SC/SO) actuators. These actuators are designed for control and on/off applications and are compatible with SOMAS valves and most 90° rotary valves.
Specifications: Type A actuators feature a patented backlash-free transmission for optimal control, low-friction seals for reduced starting torque, and standardized connections (ISO 5211 and VDI/VDE 3845). They are available in various configurations to meet different torque and air supply requirements.
Mounting and Torque: Standard mounting is perpendicular to the pipeline, with alternative positions available upon request. The actuators convert linear piston motion into rotary motion, achieving maximum torque in the closed position, suitable for ball segment, ball, and butterfly valves.
Actuator Types:
  • Double Acting (DA): Provides consistent torque throughout the operation.
  • Single Acting (SC/SO): Features spring return for fail-safe operation, optimized for compact dimensions.
Design Options: Customization options include ATEX design, high temperature design, hand operation, locking devices, larger air connections, and special designs.
Accessories: Various accessories such as positioners, solenoid valves, and limit switches can be fitted to enhance functionality.
Selection Tables: Detailed tables guide the selection of the appropriate actuator based on valve type, air supply pressure, and required torque, with separate tables for different air supply pressures (5.5 bar and 4 bar).
Key Features:
  • Compact design
  • Backlash-free torque transmission
  • Low friction seals
  • Optimized torque curve
  • Standardized connections
Technical Specifications: The document provides detailed specifications for various actuator types, including dimensions, weight, and mounting patterns. Actuators are categorized by type (double acting or single acting) and include options for high temperature design, hand operation, and special designs.
Material Specifications:
  • Housing, cover, and end cover: Aluminium with Duasolid paint
  • Cylinder: Aluminium with Duasolid paint
  • Tie rod: EN 1.4305
  • Piston seal: Carbon-filled PTFE and cold-resistant nitrile rubber O-ring
  • Screws and nuts: Acidproof steel
  • Connection options: Standard plastic tubing or optional acidproof steel tubing
Technical Specifications:
  • Air supply requirement: 4 - 8 bar
  • Rotary motion: Maximum of 95° with adjustable travel stops
  • Ambient temperature range: -40 to +90 °C, up to +120 °C with Viton O-ring
Mounting and Ordering Information: Mounting patterns follow ISO 5211. When ordering, specify the actuator type, size, function, shaft diameter, and any additional options required. An example ordering format is provided for clarity.
Contact Information:
  • SOMAS, Box 107, SE-661 23 SÄFFLE, SWEDEN
  • Phone: +46 533 167 00
  • Fax: +46 533 141 36
  • Email: [email protected]
  • Website: www.somas.se
Additional Notes: The document includes a disclaimer that SOMAS reserves the right to make improvements without prior notice. The document is identified as Edition: 2015-02 Si-503 EN.
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Catalog excerpts

Actuators Type A-1

Datasheet Pneumatic actuators Type A - DA Type A - SC Type A - SO • Compact design • Patented torque backlash-free transmission • • Optimized torque curve • Standardisedbetween connections Low friction seals Double acting actuator Single acting actuator (spring to close) Single acting actuator (spring to open) SOMAS actuators are designed for optimal function in control and on/off applications. The type A pneumatic actuators are specifically made to fit the SOMAS range of valves. They can also be used with most 90° rotary valves. The A-DA actuator is double acting and the A-SC and A-SO actuators are single acting spring return for fail safe operation. SOMAS offer a patented backlash-free transmission friction coupling (valid for D≤50) to optimize control performance and eliminate backlash. The actuators are designed to fit valves and accessories with the ISO 5211 and VDI/VDE 3845. SOMAS actuators have a torque curve corresponding to the torque demand for ball segment, butterfly, and ball valves. Low-friction seals allow for a low starting torque. Single or dual- cylinder units are used depending on the required torque and air supply pressure. Single acting actuators are optimised according to compact dimensions. The springs are supplied in a cartridge to reduce the risk of injury and to simplify maintenance. Adjustable travel stops are provided for both open and closed positions.

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Actuators Type A-2

The standard actuator mounting is perpendicular to the pipeline as shown in position A (see Fig.1). Position B, C or D is available on request (specify when ordering). Always specify mounting position when ordering. The actuator is mounted in position A if the position is not stated. The linear motion from the piston in converted into a rotary motion via a linkage mechanism. The curve shows the output torque from the actuator as a function of the actuator shaft angle (see Fig.2). Maximum torque is achieved in the closed position which corresponds to the demand of ball segment valves, ball valves...

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Actuators Type A-3

Actuator selection table for ball segment and butterfly valves (air supply min. 5.5 bar) Double acting actuator type DA Actuator Type A11-DA A13-DA A21-DA A22-DA A23-DA A31-DA A32-DA A41-DA A42-DA A51-DA A52-DA 1 Valid also for MTVL and MTVF The information will also be found in the data sheet for the actual valve type. 1 Valid also for MTVL and MTVF The information will also be found in the data sheet for the actual valve type. SC = Spring to close SO = Spring to open Design options To achieve certain functions, the actuators can be fitted with different types of accessories; such as positioners,...

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Actuators Type A-4

Actuator selection table for ball segment and butterfly valves (air supply min. 4 bar) Double acting actuator type DA Actuator Type A11-DA A13-DA A21-DA A22-DA A23-DA A24-DA A31-DA A32-DA A33-DA A34-DA A41-DA A42-DA A43-DA A44-DA A51-DA A52-DA 1 Valid also for MTVL and MTVF The information will also be found in the data sheet for the actual valve type. 1 Valid also for MTVL and MTVF The information will also be found in the data sheet for the actual valve type. SC = Spring to close SO = Spring to open Designation for low air supply (4 bar) The following actuators will have an additional code...

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Actuators Type A-5

Actuator selection table for ball valves type SKV (air supply min. 5.5 bar) Double acting actuator type DA Valve Shaft DN dia. (mm) Double acting actuator type DA Actuator for ball valve with PTFE 53 seats at ∆p (bar) Actuator for ball valve with HiCo seats at ∆p (bar) Double acting actuator type DA Valve Shaft DN dia. (mm) Double acting actuator type DA Actuator for ball valve with PTFE 53 seats at ∆p (bar) Actuator for ball valve with HiCo seats at ∆p (bar) 1 Air supply = 6 bar The information will also be found in the data sheet for the actual valve type. Single acting actuator type SC/SO...

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Actuators Type A-6

Actuator selection table for ball valves type SKV (air supply min. 4 bar) Double acting actuator type DA Double acting actuator type DA Actuator for ball valve with PTFE 53 seats at ∆p (bar) Actuator for ball valve with HiCo seats at ∆p (bar) 10 Double acting actuator type DA Double acting actuator type DA Actuator for ball valve with PTFE 53 seats at ∆p (bar) Actuator for ball valve with HiCo seats at ∆p (bar) 1 Air supply = 6 bar The information will also be found in the data sheet for the actual valve type. Single acting actuator type SC/SO Single acting actuator type SC/SO Actuator for ball...

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Actuators Type A-7

Measure T and ØD is valid only for Ødi 15-50 Mounting pattern according to ISO 5211 Actuator type A (SC/SO) single acting Type A13-F07 A23-F10 A24-F10 A33-F14 A34-F14 A43-F16 A44-F16 Weight = Weight for actuator without mounting kit 7

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Actuators Type A-8

Ordering example Pneumatic double acting actuator type A 32-DA. Mounting position A. When ordering actuators separately, please specify also the mounting kit you require for the actual valve type. Material specification Housing, cover, end cover: Aluminium (Duasolid painted) Aluminium (Duasolid painted) Piston seal: Carbon filled PTFE + O-ring made of cold-resistant nitrile rubber Acidproof steel Connection: (between actuator and accessories) Plastic tubing (standard) Acidproof steel tubing (option) Technical specification Air supply: Rotary motion: Max 95° adjustable travel stops Ambient temperature:...

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*Prices are pre-tax. They exclude delivery charges and customs duties and do not include additional charges for installation or activation options. Prices are indicative only and may vary by country, with changes to the cost of raw materials and exchange rates.