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Abu Dhabi 
(UAE)

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Electric actuators for valve


AVA Series Valve Electric Actuator:

Designed Service Life of Actuator

At the rated torque of on-off actuator, the shortest life time is 30,000 times open/close/open cycles with the assumption of maximum seating torque at stroke end and an average of 1/3 maximum seating torque during stroke.

Life Test of Valve Actuator

Standard AVA/AVAT life test of electric valve actuator is based on 10,000 time open/close/open cycles (500,000 output turns) with maximum seating torque at stroke end and an average of 1/3 maximum seating torque during stroke. Actuator is stalled 25 times against a solid object to prove its durability.

Operating Temperature of Valve Actuator

Actuators are suitable for operating in -30 deg. C  to +70 deg. C ambient temperature. Please note that the appointed operating temperature range for the hazardous area certificate should go by certificate. For temperature out side this range, manufacturer to advise.

Duty cycle

Duty cycle of motor covers S2 to S4

Vibration – Valve Electric Actuator

Standard AVA/AVAT range of actuator is suitable for the environment where the vibration dose not exceed the following standard.

Equipment induction: The cummulated vibration in 10-1000MHz frequency range must less than 1 grms.

Impact: Maximum acceleration is 5g

Seism: If it is to operate during and after the event, frequency range is 150Hz and acceleration is 2g. If it is only required to maintain structural integrity, it is 5g

Isolation control should be used or the actuator should be mounted far away from valve and drived by an extension shaft with vibration absorbing couplings in the place where it is excessive equipment induced vibration.

Noise Electric Actuator for Valves: Independent tests have shown that the noise did not exceed 61dB (A) within 1M distance.



             
Internal Structure of AVA Electric Actuator


1. Torque Measurement

Newtork actuator for vales adopts precise pressure sensor can have fast accurate detecting of output shaft torque.

2.   2. Motor & Drive

Newtork three-phase squirrel-cage a synchronous motor designed by advanced special software can work in extreme environments with F class insulation. The motor shaft and worm shaft of valve actuator are separate in order to facilitate rapid replacement for valve actuator servicing. Worm and worm shaft are immerged in lubricant to fit temperature change.

3.   3. Terminal Compartment

Separately sealed terminal compartment can make sure of the integrity of the electrical control part even when the terminal compartment cover is removed for site wiring from the electric valve actuator.

4.   4. Thrust Base

Valve Actuator Models below AVA06 are fitted with lubricated, removable type ‘A’ thrust base. Actuators can be removed without changing valve position. AVA07 and above models’ thrust bases are integrated with enclosure. Simple and removable drive bushing can be machined to fit valve stem.

5.   5. Valve Position Control

Newtork valve actuators discards traditional potentiometer to measure valve position and introduce hall incremental encoder to improve the position accuracy. Optical absolute encoder as the option can record the valve position of actuator accurately without battery when the power is off.

6.   6. Valve Position Control

Local control switch (Local / Stop / Remote) and pushbuttons are magnetic switches without penetrating shafts and control the actuator by internal magnetic reed. It can meet the requirements of tight seal and damp-proof.

7.   7. Infrared Setting

Infrared setting tool can set and diagnose valve actuator through sealed indication window without removing the electric cover. The communication distance between setting tool and window is within 0.75 meter

8.   8. Manual Operation

The handwheel (or independently geared hand wheel on larger size) of actuator can be directly driven with low speed padlockable hand/auto clutch to provide reliable emergency manual operation in the event of a power supply failure. Manual operation has lost motion ‘hammer blow’ effect, which will facilitate easy valve operation.



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AVAR Series Electric Actuators for Valves

AVAT Series Electric Actuator for Valves

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