Application and Development of Pneumatic Technology in Food Packaging Machinery

After nearly 20 years of development, China's food packaging machinery has formed a certain scale and has become an important component of the machinery industry. At present, most of the packaging work in domestic food processing, especially the more complicated packaging process, is basically manual operation, which may cause contamination of the packaged product. This situation needs to be changed. At present, the state has intensified efforts to implement the food quality and safety market access system, and food packaging equipment is gradually being incorporated into the food quality and safety access system. This is a good opportunity for the food packaging machinery industry to achieve industrial upgrading. Modern food packaging machinery is a collection of advanced technologies in a variety of disciplines, with high efficiency, high precision, high automation and high flexibility, and is developing in the direction of intelligence and integration. One of the basic components is pneumatic technology. .

Pneumatic technology is one of the effective means for automation and mechanization of production processes. It has the advantages of high speed, high efficiency, cleanliness, safety, low cost, and easy maintenance. It is widely used in the field of light industrial machinery and is also being used in food packaging and production processes. The more important the role it plays. It has a large number of applications in various types of packaging machinery, which can shorten the processing auxiliary time, reduce the labor intensity of workers, and give full play to the high-efficiency performance of the equipment.

However, food packaging machinery must meet the relevant requirements and regulations for food machinery safety, and the work site environment is generally more complex and harsh. If improper pneumatic components are used, abnormal phenomena often occur. The modern food packaging machinery usually integrates mechanical, electrical, hydraulic and pneumatic technologies, and the parts are inextricably linked. Failure of any part will affect the normal operation of the equipment. Therefore, in the design and application of the pneumatic part of food packaging machinery, we must choose reliable and practical products.

In food production, the hygiene requirements vary from one production area to another. European EN1672-2 standard defines the environment of food processing machinery as three working areas, namely food area, splash area and non-food area. According to the sanitary requirements of different regions, the pneumatic technologies and products that need to be used are also not the same.

Food and splash areas require safety and hygiene

In the food area and splash area, pneumatic technology is mainly used in the distribution, bottling, forming, filling, dispensing and sealing devices, because the pneumatic components need to directly or indirectly contact with the main production materials, in order to avoid contamination of the final product The material should be non-toxic, non-absorbent, and corrosion-resistant stainless steel. If aluminum alloy material is used, it should have certain corrosion resistance, no toxicity and no absorption. The rubber products used inside the component such as seals shall meet the corresponding hygienic requirements, shall have heat-resistance, acid and alkali resistance and oil resistance, be acceptable for normal cleaning and disinfection, be insoluble, non-toxic and non-absorbent, and must not have Affect the smell of the product. The working air filter device shall ensure that the passage of dust of 5 μm or more is prohibited, and the structure and surface shall be smooth, durable, easy to clean and can achieve good cleaning effect. Although the design of the splash zone needs to be similar to that of the food area, the material requirements may be reduced as appropriate, and it must be ensured that the design does not have a negative impact on the food product.

Typical pneumatic products used in these two environments include stainless steel cylinders, clean cylinders, easy-to-clean valve terminals, stainless steel filters, and pressure reducing valves. The most representative of these are clean cylinders, such as the PVA in Norgren, England. Series clean cylinders. The clean design of this cylinder eliminates the cavities, gaps, and sharp corners to which food particles may adhere, and has a self-draining function so that the liquid can flow off directly. Aluminium cylinder material is made of anodized aluminum, piston rod is plated with hardened stainless steel, and the seal used is polyurethane material. The cylinder as a whole meets the requirements of IP67. It is not only corrosion-resistant but also can be cleaned repeatedly. In addition, the cylinder is a standardized product that conforms to ISO6431 and is replaceable. Even the mounting parts are made of standard parts, making installation and maintenance extremely convenient.

Non-food area components increasingly stringent

In non-food areas, pneumatic technology is mainly used for sealing, packaging, labeling, inspection and capping. Although the pneumatic components in this area do not need to contact the production materials, they still need to be standardized, easy to clean, and smart. And compact structure and other features. As today's food packaging equipment requires more functionality in a confined space, the size requirements for pneumatic components are becoming increasingly stringent. Typical products include the British Norgren Easy-Clean Valve-Seat VM Series shown in Fig. 2. The valve body with a width of only 10mm can provide 430L/min flowrate, can be integrated in 2 to 20 positions, and meet IP65 and complex control in food packaging. the trend of. In addition, advanced food packaging equipment generally uses non-oil-lubricated pneumatic systems consisting of filters, pressure reducing valves, and non-lubricated valves and cylinders. Such systems pre-encapsulate grease at the locations where components need lubrication, eliminating the need for oils. The mist sprayer can work for a long time without refilling grease, which can reduce fuel consumption and cost, improve the environment, and facilitate maintenance and stable performance.

Pneumatic device intelligent

With the ever-increasing improvement of food processing technology, the level of automation of food packaging has also been continuously improved. Currently, research and development of food packaging machinery is moving in the direction of high-speed, multi-function and intelligent control, industrial robots, microelectronics, computers, and intelligent And image sensing technology will be more and more widely used, and the intelligentization and networking of pneumatic technologies used in food packaging machinery will also become inevitable.

Intelligent cylinders are the most powerful intelligent cylinders. Taking the intelligent cylinder of Norgren Corporation as an example, this type of cylinder has built-in solenoid valves and speed control valves. The cylinders provide Fieldbus and ASI interfaces, enabling remote centralized control of the bus. It has an IP66 protection rating and is easy to flush; it also conforms to the ISO/VDMA standard and can be interchanged with standard cylinders. Using this cylinder can replace the traditional whole pneumatic circuit.

Intelligent pneumatic triples enable self-diagnosis of air handling systems. Most pneumatic system failures arise from air handling systems, and intelligent triples effectively solve this problem. It can continuously monitor the pneumatic system and display related data through Fieldbus and ASI connection at any time to inform when it is necessary to replace the filter element or lubricant. The pressure state is normal and the usage time is recorded so as to minimize the failure rate and reduce maintenance. Cost, increase uptime and productivity.

The development and application of intelligent and networked pneumatic technologies will further intelligentize the food packaging machinery and realize self-diagnosis of the equipment, thus improving the automation level of domestic food packaging machinery.