Filling technology of the hottest Krones plastic b

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The filling technology of Krones' plastic bottled beer

the key lies in the oxygen absorption amount

various information prove that the domestic and foreign beer market is about to enter a hot period of sales of plastic bottles, including small capacity bottles. It is reported that in 2005, the polyester bottle filled beer will reach 3.5% of the total global beer sales

advantages and disadvantages of plastic bottles

plastic bottles for beer filling have both advantages and disadvantages. Its obvious advantages are light weight, not easy to break, flexible modeling design, high transparency, and can shape accurate dimensions. However, the plastic bottle cannot be completely vacuumized in the filling machine, so its air tightness is not good. Since atmospheric pressure plays a major role in gas exchange, oxygen will penetrate into the plastic bottle (the oxygen content in the product should be minimized) and release carbon dioxide

plastic bottles should not be overheated, which means that generally, plastic bottles cannot be pasteurized. The compressive strength of its head is limited, which affects the choice of bottle cap. When pressed or heated, its volume will change, and the bottom of the bottle will bulge and the bottle is easy to overturn. The dimensional accuracy of plastic bottle is generally higher than that of glass bottle, but it is not a standard container at the specified angle. The environmental temperature, light and handling during transportation will affect the plastic bottle. Other factors include the raw materials for making plastic bottles, the selected shape design, the blowing process and the shrinkage of finished bottles

ideal filling: constant volume filling system

generally, beer is filled into plastic bottles through the bottle washing and filling machine. With the rapid development of science and technology and the continuous improvement of automation. The washing process starts with removing the residual substances in the plastic bottle blown out by the blow molding machine. Since the oxygen in the cleaning water is always saturated, every drop of residual water will add oxygen to the beer. Therefore, it is recommended to use an electrically controlled double channel bottle washing machine to wash the plastic bottles and then dry them with sterile air

as far as the filling process is concerned, the trend of using constant volume filling system equipped with induction flowmeter is becoming increasingly obvious. This process is very suitable for precise size containers such as plastic bottles. For the filling process of sterile polyester bottles, Krones must use this isovolumetric filling system. Because it uses a long tube filling system to fill gently under the liquid level surface, plus before capping, it flushes the bottle with the gas in the annular cylinder, and then uses the carbon dioxide discharged from the clean gas channel for standby pressure, so as to maintain a very good oxygen content. The air in the polyester bottle will be discharged from bottom to top, and the effect is very good. Since the valve is not equipped with a spring device, a very good sanitary design is formed

Krones vodm-l-pet filling system first adopts off bottle air injection. Here, Krones avoids the use of dynamic seal, but uses the folding air bag valve for static seal, and then carries out slow filling and fast filling with clean gas for back pressure. Small bottles can be filled slowly and large bottles can be filled quickly. After filling, wait for a specific static time to let the large bubbles float to the liquid level, and the plastic bottle will be discharged in the same order. The effect is to achieve the same pressure. After the bottle is lowered, the filling pipe will be emptied immediately. The CIP cleaning procedure is most suitable for use in this filling system. The CIP cleaning program can be set at will by the electrical control system. This procedure ensures optimum flow conditions

impact of bottle cap category

the selection of bottle cap category has a great impact on the air in the bottle neck, the total oxygen content and the shelf life of beer. At present, the market provides a variety of cork plastic screw caps, aluminum screw caps, crown caps, screw pull bottle caps and pre sealing screw caps. These caps have their own advantages and disadvantages

pre sealing screw cap

there are two options. One is that after high-pressure sprinkler irrigation, the pre sealing cap is placed at the bottle mouth separately, and then the screw is blown. After checking the pre sealing cap position, the original screw cap is sealed

the second type is the built-in pre sealing screw cap. When the bottle cap is screwed on, the built-in sealing gasket shall be pressed against the bottle mouth, and then the screw thread injection shall be carried out, and the bottle cap shall be tightened immediately

difference in oxygenation between long tube filling machine and short tube filling machine

when beer is filled into polyester or plastic bottles, oxygenation is an important indicator. In order to compare the filling systems and bottle cap categories, the following theoretical calculation values are listed. Of course, these theoretical values may deviate from the actual situation. The numerical calculation is based on 500ml/bottle, carbon dioxide content of 5.5g/l and filling temperature of 12 ℃. Assume that the initial oxygen content in the beer is 0.05 mg/L (when washing the bottle), and the purity of carbon dioxide in the bottle is assumed to be 96% ~ 98% (with bottle washing water)

the difference between the long tube filling machine and the short tube filling machine is that in the short tube filling machine, the purity of carbon dioxide for washing bottles is 95%, while in the long tube filling machine, the purity of carbon dioxide is 98%, and the oxygen increase is 0.08 mg/L in the short tube filling machine and 0.03 mg/L in the long tube filling machine. In the latter case, it is assumed that a vodm-l-pet filling machine with pure CO  2 backup pressure is used. After the beer was injected into the bottles by these two filling machines under high pressure, the empty Chinese plastic extruder Market in the bottleneck space also made great progress and breakthrough. The gas content was 0.35 mg/bottle

the total amount of oxygenation reaches about 0.18 mg/L (according to Ulrich and vilacha Uhlig & vilacha's law) when using crown caps, screw pull caps or screw caps with pre sealing

in another case, if the aluminum screw cap is used, the total amount of air of about 10.5 ml must be taken into account. However, it should also be estimated that under extremely adverse circumstances, 30% of the total air will be compressed into the bottle. The rest will leak along the thread, resulting in an actual additional air volume of 3.15 ml

this situation is more obvious when using plastic bottle caps without pre sealing. Because the plastic bottle cap is opposite to the aluminum screw cap, the bottle mouth has threads, and the gap between the bottle mouth threads and the cap threads is very small. It is estimated that only half of the air leaks through the threads. Therefore, in the worst case, the air volume will be increased by 5.25 ml. According to this point of view, we should try to use screw caps with pre sealing, screw pull bottle caps or crown caps

relationship between total oxygen content and bottle volume and bottle cap type

from a series of tests, Krones put the oxygen increase of 500ml glass bottle with crown cap and 500ml polyester bottle with plastic screw cap together for comparative determination: oxygen increase in liquid (unit: mg/L) The oxygen increment (unit: mg/L) and total oxygen content (TPO for short, unit: mg/L) of the air in the bottleneck space. The amount of oxygen flowing from the sake tank reaches 0.05 mg/L. Through comparison, it can be clearly seen that there is a great difference between the glass bottle and the polyester bottle. In the polyester bottle, the pressure value of oxygen content in the space from the bottleneck is the highest

since the air pressure in the bottle neck is related to the filling volume, the bottle size is inversely proportional to the value. The larger the bottle, the better

capable of arbitrary conditioning, accuracy: superior to the indicated value ±, main motor source: 0.7kw, AC220V ±, host experimental stroke 800mm, host weight, LCD display content: experimental force, displacement, peak value of experimental force, operation status, etc. regardless of market demand, in order to maintain the pure taste of the filling products, these process factors will have an impact on the selection of filling bottles and their caps. (end)

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