Switch Compartment 8 Design Principle Motor To unseat valves from end positions high starting torque is required, which is provided by the motors developed by Auma India. Change Gears Auma actuators are driven by special combination of gears, which are outside the grease filled housing and require no lubrication. This allows torque switch to be released. If control system provides continuous signal, this results in hunting of motor. This can be avoided by the use of auxiliary relay.
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Switch Compartment 8 Design Principle Motor To unseat valves from end positions high starting torque is required, which is provided by the motors developed by Auma India. Change Gears Auma actuators are driven by special combination of gears, which are outside the grease filled housing and require no lubrication. This allows torque switch to be released.
If control system provides continuous signal, this results in hunting of motor. This can be avoided by the use of auxiliary relay.
Note on Self Locking: Self locking gearing does not ensure safe stopping after an operation. If this is required, separate locking arrangement must be provided. Output Speeds Switch Compartment With large range of available output speeds, almost every required time can be achieved with Auma actuators. Depending upon type of valve, the actuator must be switched off at the end positions by limit switch or torque switch.
For this purpose, independent limit switching or torque switching devices are provided in the switch compartment. The switching devices are easily accessible for any setting at site.
The output speeds are available from 4 - rpm. During trial run, if found necessary, the output speed can be easily changed by exchanging the change wheels at site. The grease filled housing need not be opened for this purpose. For actuators with output drive A Stem nut , max. Screw type connectors are also provided as an option. For detailed information, refer page Valve Attachment For higher velocities, it is recommended to use spring loaded stem nut type AF special design.
Various output drives are available for adaption to various types of valves. Reduction Gearing Mounting Position A well proved principle of worm gearing is used to reduce the motor speed to required output speed of actuator. Self locking feature is achieved by worm gearing up to 90 rpm at output.
Worm shaft and output shaft with worm wheel run in ample sized bearings. The sliding worm is positioned between two sets of springs on worm shaft. The worm moves axially in relation to thrust, which is the measure for torque.
Auma actuators with or without integral starters can be operated without restriction in any mounting position. Self Locking Manual Operation Electric actuators have a handwheel to enable operation of the actuator during commissioning or in case of power failure. If the actuator motor is switched on again after manual operation, the handwheel is automatically disengaged from the motor drive.
After receiving command, the actuator operates the valve to one of the end positions or if necessary to a preset intermediate position. The frequency of operation of valves can span between a few minutes to several months. The duration of short time is limited to 15, 30 or 60 min. Intermittent Duty S4 A sequence of identical duty cycles, each cycle including a significant period of starting, a period of operation at constant load and a rest and de-energized period.
These periods being too short to attain thermal equilibrium during one duty cycle. The mechanical components and motors are designed to withstand a large number of operations required for modulating applications. The details are available in data sheets. The valve travel is measured by mechanical counter gear mechanism, which when reaching the set switching points, operate the electrical limit switches by cams.
In limit switching, Two train counter gear and Four train counter gear versions are available. The number of spindle turns can be set between 1 and or 1 and The torque switching enables to switch off the actuator when pre-determined torque is reached. The torque switching works on principle of sliding worm. Axial displacement of worm proportional to thrust is transmitted to torque switches. The required tripping torque can be easily set on the graduated dial and can be read directly in daNm.
If limit switch cut off is selected prior to torque switch, then torque switch serves as overload protection. However, if two additional intermediate switching positions are desired, Four train counter gear is required.
This limit switching has four counter gears and four limit switches. Two counter gears are used to switch off at end positions as in Two train counter gear while the other two are available for setting any desired intermediate positions between end positions. After cam actuation, the switches remain actuated till reaching end of valve travel. Example of such applications are: l To stop at intermediate position. Such operation can be carried out by torque seating.
Limit seating is commonly used in the end position OPEN. When torque seating is used at end position, limit switches can be used for signalization. Therefore, actuator controls can differentiate whether actuator was switched off by torque switch or by limit switch.
Torque Switching Running Indication Blinker switch is provided in the actuator and can be used as running indicator. Limit switches are tripped when an end position is reached and torque switches are tripped when the set tripping torque is exceeded. For such applications, a relay is recommended since there may be small differences in tripping points of tandem switches.
The micro switches are individually sealed to enclosure protection class IP 66, as per IS The micro switches have double break change over potential free contacts. The circuit is interrupted simultaneously at two points. The basic versions of the switch contacts are of silver. For low current ratings, micro switches with gold plated contacts are available as an option. Single Micro Switch Limit or torque switches in tandem version have additional switching contacts.
AUMA ACTUATOR CATALOGUE PDF
Analogue setpoints or measured values are When testing the complete actuator, the switch compartment 1is the perfect place for mounting Sincethe founding year of thecompany, AUMA has The Online Industrial Exhibition. Actuators from that time are still in use today cata,ogue proves the opera- tional reliability of these devices. Lever actuators SGF Open the catalog to page 3. The operating behaviour of the field devices can be optimised during operation without gaining access to the device. Theheart of the plant is a coke drum with a height of more than 40metres where Traditional values like reliability, quality, and sustainability are deeply rooted. Open the catalog to page 2. From the very beginning to the present, we have been striving to support our customers all around the globe, assist them with competent excellence and offer comprehensive local and on-site service.
Actuators SA and SAR
This means that the actuators have to operate the valve correctly under defined conditions and to remain safely operable even under AUMA is one of the leading electric actuator manufacturers worldwide and has been manufacturing electric power plants for more than 25 years. Actuators from that time are still in use today which proves the opera- tional reliability of these devices. This corresponds to the violet section in the illustration. The actuators can be adapted to suit the requirements of nearly all valve applications. This is achieved by: Graded protection concept In a compact, solid and DBE resistant housing in enclosure protection IP 68, components are installed which are themselves qualified for DBE conditions. All outer housing components are made of aluminium free materials.