explosion-proof-electric-actuator

Advantages Of Explosion-proof Electric Actuator

Explosion-proof electric actuators are used to control valves that rotate from 0 to 270 degrees, such as ball valves and butterfly valves. Widely used in petroleum, chemical industry, water treatment, shipbuilding, paper making, power station and other industries. It uses 380V / 220V power supply as the driving power supply, and uses the switch signal or analog signal as the control signal, which can move the valve to the desired position and realize its automatic control. Excellent sealing performance, less prone to accidents, suitable for explosive and dangerous scenes. And with a hand wheel, you can manually control the switch.

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The advantages of explosion-proof electric actuators:
1. Hard aluminum alloy, anodized and polyester powder coating, strong corrosion-resistance, protection grade IP67.
2. Fully enclosed squirrel cage click, small size, large torque, built-in overheat protection switch, can prevent the electric actuator from blocking the motor and damaging the motor when it overheats.
3. The design of the handwheel guarantees safety, reliability, labor saving and small size.
4. There is an indicator on the top of the valve to observe the valve position.
5. The torque switch can provide overload protection. When the valve is stuck, the motor power is automatically disconnected, and the over-torque alarm indication is output, which can effectively protect the valve and the electric actuator from damage.
6. The precise double worm gear mechanism can efficiently transmit large torque, high efficiency, low noise, long life, stable and reliable, and has a self-locking function to prevent inertial transmission and reverse transmission.
7. All screws are made of stainless steel, anti-corrosion, and suitable for outdoor use.

All in all, explosion-proof electric actuator will be your best choice of actuator. Wide application range and large torque. Any demands, please leave a message to us!

pneumatic-actuator

How To Select Pneumatic Actautor And Electric Actuator?

COVNA is a manufacturer of quarter-turn electric actuator and rack and pinion pneumatic actuator. Any demand, please contact us at sales@covnavalve.com

An actuator is a device that opens or closes valves with power drive and signal control for easy industrial automation. The actuator can be driven by voltage, current, or pneumatic, or even manual, and it responds by converting energy into mechanical motion.

Actuators can be used with ball valves, butterfly valves, gate valves, globe valves, knife gate valves and a wide variety of valves used to control or cut off the media. By setting the control signal in advance, the energy source can be automated through the system without the need for an engineer to be there to open it. When working in hazardous or harsh environments, actuators are a good option to reduce labor and casualties.

Actuators can be divided according to the energy drive: electric actuators, pneumatic actuators and hydraulic actuators.

What Is An Electric Actuator?

An electric actuator is an electrical device that converts electrical energy into mechanical torque, providing power to open or close a valve. The main advantages of electric actuators are high stability, High Torque, can work for a long time, through the signal source control (PLC control), adjustable open angle, overload protection functions, self-locking protection functions, and so on.

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What Is a Pneumatic Actuator?

Pneumatic actuators are pneumatic devices that convert the origin of compression into a mechanical torque that can quickly open or close a valve. The main advantages of pneumatic actuators are quick response, fast open speed, large load, can adapt to high torque output applications, good adaptability to the working environment.

How To Choose Between The Electric Actuator And Pneumatic Actuator?

1. From the price aspect, the electric actuator’s price is higher than the pneumatic actuator.
2. In terms of opening speed, the pneumatic actuator opens faster than the electric actuator
3. From the installation aspect, the electric actuator needs wiring or the adjustment signal control. Pneumatic actuators require a compressed air system.
4. The electric drive with a servo motor has the advantage when the force increases rapidly and accurate feedback is needed. For applications that require an accurate, synchronous operation, adjustability, and prescribed feedback programming, an electric drive is a better choice, the electric drive system composed of Servo or stepping motor with closed-loop feedback controller can supplement the deficiency of pneumatic system.

The electric actuator and the pneumatic actuator both have the same function, which is to regulate and control the flow of the medium. How you choose depends on the design of your project, as well as the cost estimates.

Please tell us your needs and budget, we will do our best for you to choose the appropriate actuator, to help you save money and effort. Email to sales@covnavalve.com

covna-electric-actuator-valve

Working Environment of Electric Actuator Valve

Electric Actuator Valve is divided into electric ball valve, electric butterfly valve, electric gate valve and electric globe valve. High Torque, long working hours, low failure rate, easy maintenance, adjustable switching speed / angle, widely used to control the air, water, steam, mud, oil and various corrosive media of the fluid.

Electric Actuator Valve can achieve remote control, PLC control, manual control and so on, its movement process can be controlled by the stroke, torque or the size of axial thrust. Can be used with the different valve body, to replace the implementation of different models to be used in various types of pipelines, suitable for all types of media. Because the electric valve device operating characteristics and utilization depend on the type of valve, device specifications and valve in the pipeline or equipment location. Therefore, the correct choice of electric valve, can effectively prevent the phenomenon of overload, improve cost-effectively.

Diesel Oil transfer

The electric device in the electric actuator valve is mechanical and electrical equipment, and its working conditions are greatly affected by its working environment. In general, electric actuator valves operate in the following types of environments:

1. With flammable, explosive gas or dust environment.

2. The environment of a ship or dock (salt spray, mold, moisture).

3. Where there is severe vibration.

4. Fire prone situations

5. The environment in Humid and dry tropical regions.

6. The temperature of the pipe medium is over 480 °C

7. Indoors or with protective measures for outdoor use.

8. Outdoor installation, wind, sand, rain, sun and other erosion.

9. Ambient temperature below-20 °C.

10. Susceptibility to flooding or submergence.

The environment with radioactive materials (nuclear power plants and radioactive material test facilities).

For the electric actuator valve in the above environment, the electric device structure, materials and protective measures are different. Therefore, should be based on the above-mentioned working environment to select the appropriate valve electric device.

how-to-select-the-right-valve

3 Tips For How To Select The Right Valve

COVNA, as a valve manufacturer over 20 years who specialized in pneumatic actuator, electric actuator, ball valve, butterfly valve, gate valve and globe valve. Any demand, please contact us and we will offer the cost-effective valve solution for you.

In fluid piping systems, the valve is the control element, its main role is to isolate equipment and piping systems, regulate flow, prevent backflow, regulate and discharge pressure. Since it is important to select the most suitable valve for the piping system, it is important to understand the characteristics of the valve and the procedure and basis for selecting the valve.

1. Characteristics Of Valves
Use Characteristics: It determines the main performance and use of the valve, the use of the characteristics of the valve are: Valve Types (closed-circuit Valves, control valves, safety valves, etc.) ; Product Types (gate valves, globe valves, butterfly valves, ball valves, etc.) ; Valve Main Parts Material (body, cover, stem, disc, sealing surface) ; valve drive mode

Structural characteristics: It determines some of the structural characteristics of valve installation, repair, maintenance, etc. , structural characteristics include: The structural length and overall height of the valve, and pipe connection form (flange connection, thread connection, clamp connection, external thread connection, welding end connection, etc.) ; Sealing surface form (insert ring, thread ring, build-up welding, spray welding, valve body) ; Valve stem structure form (rotating rod, lifting rod) and so on.

2. Valve Selection Procedure
1) Specify the use of the valve in the equipment or device and determine the working conditions of the valve: applicable medium, working pressure, working temperature, etc. .
2) Determine the nominal diameter and connection mode of the pipe to the valve: Flange, thread, welding, etc. .
3) Determine how to operate the valve: manually, electrically, electromagnetically, pneumatically or hydraulically, electrically or electrohydraulically.
4) According to the medium of pipeline transportation, working pressure and working temperature, the materials of the shell and inner parts of the selected valve are determined: gray cast iron, malleable cast iron, ductile Iron, carbon steel, alloy steel, stainless acid-resistant steel, copper alloy, etc. .
5) Select the type of valve
6) Determine the type of valve
7) Determine valve parameters: for automatic valves, according to different needs, first determine the allowable flow resistance, discharge capacity, back pressure, and then determine the nominal diameter of the pipeline and valve seat hole diameter.
8) Determine the selected valve geometric parameters: structural length, flange connection type and size, after opening and closing the size of the valve height direction, connecting the size and number of bolt hole, the overall valve shape size. Use The available information: valve product catalog, valve product sample, etc. to select the appropriate valve product.

3. Valve selection basis
1) The use, operating condition and control mode of the valve selected.
2) The nature of the working medium: working pressure, working temperature, corrosion performance, whether it contains solid particles, whether the medium is toxic, whether it is flammable, explosive medium, medium viscosity and so on.
3) Requirements For Valve Fluid Characteristics: flow resistance, discharge capacity, flow characteristics, seal rating, etc. .
4) Installation size and outline size requirements: nominal size, connection with pipe and connection size, outline size or weight limit, etc. .
5) Additional requirements for reliability, service life of valve products and explosion-proof performance of electric installations.