What Is Pneumatic Accessories?

Pneumatic accessories are industrial equipment used to realize industrial automation. There are positioners, limit switches, pneumatic reversing valves, air filters, etc. for your choice. Each pneumatic accessory has a different function. It is generally used with various types of pneumatic valves, which is convenient for remote control and industrial automation to improve the production efficiency of the project.



A positioner is an industrial device that receives or feeds back signals and delivers air to a pneumatic actuator to adjust valve opening and closing.
● Responsive and precise adjustment
● Available in single-acting types and double-acting types
● Explosion-proof type is available for the dangerous applications
● Helping you control the valve remotely

Limit Switch

The limit switch is an industrial device that feedbacks the opening and closing of the valve body. At the same time, it can feedback signals to the system, so that you can know the status of the valve by checking the system.
● Clear viewing window for easy observation of valve opening and closing
● IP67 protection grade can be used normally outdoors
● Explosion-proof type is available for the applications required.

Pneumatic Reversing Valve

Pneumatic reversing valve is an industrial equipment controlled by electromagnetic. Mainly used to control fluid automation basic components, and to control the opening and closing of pneumatic valves. The action is accurate, the degree of automation is high, and the work is stable and reliable.

Air Filter

An air filter is a filter used to filter impurities in the air so that clean air can be the driving source. In order to make the pneumatic valve run more smoothly and have a longer working life.

The above is the introduction of the pneumatic accessories provided by COVNA. If you have a demand for a complete set of pneumatic valves, you are welcome to consult us to obtain the optimal valve solution and cost budget.

COVNA Actuator Valves For Mechanical Vapor Recompression

Mechanical vapor recompression is an industrial system for seawater desalination, metal processing plants, and food processing plants. It is used for waste & wastewater treatment, improving water resource utilization and waste treatment rate, and making our living environment more environmentally friendly. Since 2000, COVNA helped more than 500 wastewater treatment projects with automated valve solutions. In this article, we will recommend actuator valves for mechanical vapor recompression based on our knowledge of the product and our knowledge of wastewater treatment projects.

Since the medium of wastewater treatment projects will contain a certain degree of corrosiveness, we will recommend stainless steel valves or fluorine-lined valves to customers.

Stainless Steel Valve

The valve body and ball/disc are made of stainless steel 304/316/316L and can withstand media from pH 1 to 14. Provide you with corrosion-resistant fluid solutions.

Stainless steel valves can be divided into stainless steel ball valves, stainless steel butterfly valves, stainless steel gate valves and stainless steel globe valves for your choice.


Fluorine-lined Valves

The valve body is cast steel. The ball/valve plate and seals are all PTFE, and the seals will be thickened. PTFE has excellent corrosion protection properties, making it ideal for regulating flows containing aggressive media.
Fluorine-lined valves can be divided into fluorine-lined ball valves and fluorine-lined butterfly valves.

The pipelines of wastewater treatment projects are divided into different levels of areas according to the processing steps. Therefore, some processing areas need to use ball valves, and some areas need to use butterfly valves or gate valves.

Ball Valves

Ball valve is a commonly used valve. Suitable for flow-through, cut-off and regulation. The advantages of ball valves are their high pressure-bearing capacity, high-temperature tolerance and various installation methods. But the size range of the ball valve is limited. The cost of a large-sized ball valve may exceed your budget.

According to the flow direction requirements, the ball valve can be divided into two-way type or three-way type to meet your needs of confluence, diversion or changing the flow direction of the medium. According to the structure type, the ball valve can be divided into floating ball valve and fixed ball valve to meet your different pipeline needs.

Butterfly Valves

The butterfly valve is a quarter turn valve. The butterfly plate rotates 90 degrees with the valve stem to open or close the valve. It is suitable for on-off and control the flow rate. The advantages of butterfly valve lie in its compact design, large size range and various installation methods, which can match the installation of various pipelines. But the pressure bearing capacity of the butterfly valve is low.

Gate Valves

The gate valve is a linear operated valve. The valve plate moves straight up or down with the valve stem to open or close the valve. The gate valve can only be fully opened or fully closed, so it is suitable for circulating or blocking medium flow.

Actuator Types

The above valves can be driven by electric actuator, pneumatic actuator or handle/Gearbox. Meet your remote control and on-site control needs.


Check Valves(Non-return Valves)

The check valve is a valve that prevents the backflow of the medium, thereby ensuring the normal operation of the pipeline.


The Y-strainer is a valve used to filter impurities in the media. Thereby extending the working life of valves and pipes.

The above are valves commonly used in wastewater treatment projects and mechanical vapor recompression. If you have a demand for valves, you are welcome to consult us to obtain the optimal valve solution and cost budget. sales@covnaactuator.com

COVNA Actuator Valves For Industrial Tunnel Washers

Industrial tunnel washers provide large-scale and environmentally friendly commercial washing services. Able to use less water, and wash more cleanly. Valves play a role in conveying water or detergent in industrial tunnel washers. Helping industrial tunnel cleaners run smoothly and improve efficiency. Below, we will introduce you to the valves that can be used in industrial tunnel cleaning machines.

Ball Valves

The ball valve is a quarter-turn valve. It can assist the pipeline to realize the functions of circulation, cut-off, changing the flow direction of the medium, confluence and diversion. So the ball valve will be one of your first choice valves.

● According to the function, the ball valve can be customized into high-temperature types (suitable for controlling steam, hot water, etc.), high-pressure types (suitable for high-pressure cleaners), anti-corrosion types (suitable for controlling strong acids and alkalis, etc.), general-purpose types (suitable for for regulating ordinary water flow, etc.).

● According to the difference of the actuation mode, the ball valve can be divided into electric ball valves, pneumatic ball valves and manual ball valves. 3 actuation methods to meet the actuation needs of your project.


Butterfly Valves

The butterfly valve is a valve with a compact design, easy to operate, and a large size. It can save you installation space and purchase cost. Provide you with the services of circulation, truncation and regulation of traffic.

● Butterfly valve can be divided into soft seal butterfly valve and hard seal according to the difference of seals. Meet different temperature and pressure needs.

● According to the difference of the connection method, the butterfly valve can be divided into wafer type, flange type, lug type and clamp type to meet various installation needs of your pipeline.

● According to the driving method, butterfly valve can be divided into electric butterfly valves, pneumatic butterfly valves and manual butterfly valves. All in all, electric actuators are your first choice for smart devices. Pneumatic actuators are fast and cost-effective. Manual valves are low cost.


Gate Valves

The gate valve is a linear operated valve. It is suitable for flow-through and shut-off. Its advantages are easy installation and easy handling.

Check Valves

The check valve is an industrial valve used to prevent the backflow of the medium and ensure the normal operation of the project.

The above is an introduction to the valves that can be used in industrial tunnel cleaning machines. If you are an industrial tunnel cleaning machine manufacturer or other industrial equipment manufacturers, welcome any inquiry to sales@covnaactuator.com.


Why Choose Pneumatic Sanitary Valves?

Pneumatic sanitary valves are electronically polished as standard, and the smooth surface ensures cleanliness with no areas of media accumulation and potential contamination.

Other valves will be customized to meet the needs of the project, such as replacing seals and changing component materials to withstand high pressures or temperatures. But they do not have the same refinement as sanitary valves. So if you are from the food processing industry or have a need for sanitary safety, sanitary valves will be your first choice.

At the same time, pneumatic actuators have fast switching speed, which can match the food processing industry’s requirement for switching speed, and the cost of pneumatic actuators is low. Therefore, pneumatic sanitary valves are very suitable for the food processing industry.

Valve Body Materials

Sanitary valves can be made of 304SS, 304L or 316, 316L stainless steel. After production and processing, they have undergone special treatment, while other valves can be made of cast iron, cast steel, ductile iron, stainless steel, and a wider range of materials.
Because sanitary valves are used in pharmaceuticals, food, daily chemicals, etc., which have high sanitary requirements, these products are all edible or in direct contact with the human body, Sanitary grades are also used in environments with strict health regulations that require a zero-tolerance policy for physical and chemical hazards.

All sanitary valves must be sterilized in order to meet certain health standards. Non-hygienic valve manufacturers cannot produce such valves because all toxic components (such as lead) must be removed, which can lead to poisoning, cancer and even death. Therefore, most sanitary valves are made entirely of stainless steel.

However, ordinary valve materials such as steel, iron, copper and other materials cannot be satisfied. First of all, steel and iron are used as valves. If the humidity in the liquid or air is relatively high, they will corrode and rust, thereby polluting the product. The same is true for copper valves, and the patina is also a toxic substance, so it cannot be used as a sanitary valve.


Sealing Material

COVNA’s pneumatic sanitary valves all use food-grade silicone seals and are de-oiled. This makes the seals more suitable for food grade and for use in the food processing industry.


Sanitary valves generally adopt the way of clamp quick installation connection. While the connection methods of industrial valves include flanged, thread, welding, etc. Compared to other industrial valve connections, the clamp connection used in sanitary valves effectively prevents food from accumulating in the connection, better protecting the safety and hygiene of food.

COVNA pneumatic sanitary valve has the following advantages:

  • Seamless
  • Easy to clean
  • Smooth and polished surface
  • These properties allow the product to flow cleanly and remain sterile without the risk of bacterial growth or other forms of contamination.


If you have a demand for pneumatic sanitary valves, feel free to consult us at sales@covnaactuator.com for suitable valve solutions.