The expansion of the application of pneumatic technology is a sign of the development of the pneumatic industry. The application of pneumatic components is mainly in two aspects: maintenance and matching. In the past, the sales of domestic pneumatic components were used for maintenance, and the sales share directly for the main supporting equipment increased year by year. The application of domestic pneumatic components ranges from metallurgical equipment worth tens of millions of yuan to chairs of only 1-2 hundred yuan. Specially developed domestic pneumatic components are used in railway turnouts, locomotive wheel and rail lubrication, train brakes, street cleaning, lifting equipment in special workshops, and military command vehicles. This shows that pneumatic technology has "penetrated" into all walks of life and is expanding day by day.
Although my country's pneumatic industry has reached a certain scale and technical level, compared with the international advanced level, there is a big gap. The output value of my country's pneumatic products only accounts for 1.3% of the world's total output value, only 1/21 of the United States, 1/15 of Japan, and 1/8 of Germany. This is very disproportionate to a large country with a population of more than 1 billion. In terms of varieties, a Japanese company has 6,500 varieties, and our country only has 1/5 of it. There is also a large gap in product performance and quality levels.
As pneumatic technology is more and more applied to equipment for automatic assembly and automatic processing of small and special items in various industries, the performance of the original traditional pneumatic components is constantly improving, and new products that meet market requirements have been developed one after another. The variety of pneumatic components is increasing day by day, and its development trend mainly has the following aspects:
Smaller size, lighter weight, and lower power consumption. In the manufacturing industries of electronic components and pharmaceuticals, the size of pneumatic components is bound to be limited due to the small size of the processed parts. Miniaturization and light weight are the first priority for pneumatic components. a direction of development. Foreign countries have developed ultra-small solenoid valves that are only the size of a thumb and have an effective cross-sectional area of 0.2mm2. It is more ideal to be able to develop components with small dimensions and large flow. For this reason, the flow rate has been increased by 2~3.3 times for valves with the same external dimensions. There is a series of small solenoid valves with a body width of only 10mm and an effective area of up to 5mm2; a width of 15mm and an effective area of up to 10mm2.
The power consumption of foreign solenoid valves has reached 0.5W, and will be further reduced to adapt to the combination with microelectronics.
Most of the air source treatment assemblies at home and abroad adopt the building block structure, which is not only compact in size, but also convenient in combination and maintenance.
The positioning accuracy of the actuator is improved, the rigidity is increased, the piston rod does not rotate, and it is more convenient to use. In order to improve the positioning accuracy of the cylinder, the application of the cylinder with a brake mechanism and a servo system is becoming more and more common. With the cylinder with servo system, the positioning accuracy of ±0.1mm can be obtained even if the air supply pressure and the applied load vary.
At international exhibitions, there are many cylinders with various special-shaped cross-section cylinders and piston rods. Since the piston rod will not rotate, this type of cylinder can maintain a certain accuracy without additional guide devices when applied to the main engine. In addition, many cylinders and cylinder slide assemblies with various guide mechanisms have been developed, such as cylinders with two guide rods, double piston rods, double cylinder cylinders, etc.
The shape of the cylinder barrel is not limited to a circle, but square, square or other shapes. Guide grooves, installation grooves for sensors and switches, etc. are opened on the profile to make installation and use more convenient for users.
Multifunctional and complex. In order to facilitate users and meet the needs of the market, various small pneumatic systems combined with multiple pneumatic components and equipped with control devices have been developed. For example, the components used to move small items are composed of two cylinders with guides according to the X-axis and Z-axis respectively. The assembly can move 3kg heavy objects, equipped with solenoid valves and program controllers, has a compact structure, takes up little space, and the stroke can be adjusted. Another example is a loading and unloading module, which has seven modules with different functions, which can complete the loading and unloading operations on the precision assembly line, and different modules can be combined arbitrarily according to the job content. Another type of manipulator is an assembly of a swing cylinder and a chuck that has a small shape and can change the swing angle. There are several types of chucks that can be selected for the chuck.
Combined with electronic technology, a large number of sensors are used, and the pneumatic components are intelligent. Cylinders with switches have been widely used in China. The switches will be smaller in size and higher in performance, and can be embedded in the cylinder body; , making the system more reliable. Using sensors instead of flowmeters and pressure gauges can automatically control the flow and pressure of compressed air, which can save energy and ensure the normal operation of the device. Pneumatic servo positioning system has already entered the market. The system uses a three-position five-way pneumatic servo valve, compares the predetermined positioning target with the detection data of the position sensor, and implements negative feedback control. When the maximum speed of the cylinder reaches 2m/s and the stroke is 300mm, the positioning accuracy of the system is ±0.1mm. A new type of intelligent solenoid valve was successfully trial-produced in Japan. This valve is equipped with a logic circuit with sensors, which is the product of the combination of pneumatic components and optoelectronic technology. It can directly receive the signal of the sensor. When the signal meets the specified conditions, it can complete the action by itself without going through the external controller to achieve the control purpose. It has been applied on the conveyor belt of objects, which can identify the size of the objects being transported, so that large items can be sent down directly, and small items can be shunted.
Higher safety and reliability. It can be known from the international standards of pneumatic technology that the standards not only propose interchangeability requirements, but also emphasize safety.
Many application occasions of pneumatic components, such as rolling mills, textile assembly lines, etc., cannot be interrupted due to quality problems of pneumatic components during working hours, otherwise huge losses will be caused, so the reliability of pneumatic components is very important. There are a lot of pneumatic components used on sailing ships, but there are not many pneumatic component factories that can enter this field. The reason is that they have particularly high requirements for the reliability of pneumatic components and must pass relevant international machinery certification.
To develop in the direction of high speed, high frequency, high response, and high life. In order to improve the production efficiency of production equipment, it is imperative to increase the working speed of actuators. The working speed of the cylinder in our country is generally below 0.5m/s. According to the prediction of Japanese experts, the working speed of most cylinders will be increased to 1~2m/s after five years, and some require up to 5m/s. The improvement of the working speed of the cylinder requires not only the improvement of the quality of the cylinder, but also the corresponding improvement in the structure, such as the configuration of hydraulic shock absorbers to increase the cushioning effect. The response time of the solenoid valve will be less than 10ms, and the service life will be increased to more than 50 million times. There is a gap-sealed valve in the United States. Since the valve core is suspended in the valve body and does not contact each other, it has a service life of up to 200 million times without lubrication.
Oil-free lubrication technology is widely used to meet certain special requirements. Due to environmental pollution and the requirements of electronics, medical, food and other industries, oil is not allowed in the environment, so oil-free lubrication is the development trend of pneumatic components, and oil-free lubrication can Simplify the system. Lubricators in the European market are obsolete products, and oil-free lubrication is generally achieved. Furthermore, in order to satisfy certain
Special requirements, deodorization, degerming and precision filters are being continuously developed, the filtration precision has reached 0.1~0.3μm, and the filtration efficiency has reached 99.9999%.
Pneumatic seals made of polytetrafluoroethylene-based composite materials are heat-resistant (260°C), cold-resistant (-55°C) and wear-resistant, and are used in more and more occasions.
In order to improve the quality, new technologies such as vacuum die-casting and hydrogen-oxygen explosion deburring are being gradually promoted in the manufacture of pneumatic components.
It is easy to maintain, repair and use. Foreign countries are studying the use of sensors to realize pneumatic components and systems with fault prediction and self-diagnosis functions.
It can be known from the development direction of pneumatic technology mentioned above that we have a lot of work to do in the development of pneumatic products. Any pneumatic component factory, even if its scale is small, can occupy a place in the market and survive and develop in the fierce competition as long as it breaks through in one aspect and maintains technological leadership.
The main component of the life-saving thrower is a firing gun body with a built-in cylinder and a folding buttstock, which is a typical application of pneumatic products. It has played a very important role in water lifesaving and land rescue.
The market trend of pneumatic components The development direction of pneumatic components: higher safety and reliability. It can be seen from the international standards of pneumatic technology that the standards not only propose interchangeability requirements, but also emphasize safety. The pressure of the pressure test of pipe joints, gas source treatment shells, etc. is increased to 4 to 5 times the working pressure, and the pressure resistance time is increased to 5 to 15 minutes, and the test should be carried out at high and low temperatures. If these international standards are implemented, it will be difficult for domestic cylinder barrels, end covers, air source treatment castings and pipe joints to meet the standard requirements. In addition to the pressure test, certain regulations have also been made on the structure, such as the external regulation of the transparent shell for gas source treatment to add a metal protective cover.