In the packaging production of food, daily chemicals and other fields, the capping mechanism is a key device to ensure the sealing of bottles, cans and containers. It closely combines the bottle and the cap through threaded connection, preventing the leakage and deterioration of the contents. Its design and working principle directly affect the sealing efficiency and quality.
The core logic of screw cap sealing is not complicated. The sealing part of the bottle can is pre-processed with external threads, while the inner side of the bottle cap is correspondingly made with internal threads. The two are like screws and nuts, and are connected by rotation. Bottle caps are mostly made of thin metal sheets or plastic, and are usually lined with elastic sealing gaskets inside. However, new types of screw-top plastic caps with sealing structures or bottle caps that use stoppers as sealing elements can omit this sealing gasket. When sealing, place the bottle cap with a sealing gasket at the bottle mouth. During the twisting process, the pressure generated will squeeze the elastic sealing gasket, causing it to undergo elastic deformation and thus fill the gap between the bottle mouth and the bottom of the cap, meeting the sealing requirements.
FAQ
Q: How does the screw cap seal achieve the sealing of bottles and cans?
A: The screw cap sealing is accomplished through threaded connection. The sealing part of the bottle or can has external threads, and the inner side of the bottle cap has matching internal threads. Moreover, the bottle cap is usually lined with an elastic sealing gasket (some new types of screw-mouth plastic caps or bottle caps with stoppers as sealing elements may not have this gasket). When sealing, place the bottle cap with a sealing gasket on the bottle mouth. The pressure generated by twisting causes the elastic sealing gasket to undergo elastic deformation, closely adhering to the bottle mouth and the bottom of the cap, thus achieving a sealed connection.
Q: What are the two main ways of threaded connection sealing for bottles and cans?
A: What are the characteristics of the threaded connection sealing of the bottles and cans used for canned food packaging? The threaded connection sealing of bottles and cans is mainly divided into two types: multi-head threaded connection sealing and single-head threaded connection sealing. Canned food packaging bottles and cans are sealed by multi-head threaded connection. To facilitate opening, the sealing joint part is made with 3 or 4 threaded sections for connection. The length of each threaded section is approximately 1/3 of the total length of the entire thread circle, with a relatively large lead. The thread is a universal thread, and there are protruding claws corresponding to the number of threaded heads on the bottle cap, and an elastic rubber ring is lined inside.
Q: What steps are involved in the pneumatic capping process?
A: What are the advantages of this type of screw cap? The pneumatic capping process is carried out in sequence as follows: removing the cap, lifting the cap, holding the cap, centering the bottle mouth, capping, removing the cap and resetting it, and then entering the next working cycle. The deformation of the rubber body by pushing the pressure block, the holding of the cover, and the control of the rotational motion input into the clutch are all achieved through pneumatic means. This type of screw cap has the advantages of sensitive movement, smooth and stable combination, and reliable operation. It belongs to a relatively advanced type of screw cap.
Q: What is the function of the friction plate in the three-jaw screw cap mechanism?
A: Then how to adjust the height of the screw cap to adapt to bottles of different heights? In the three-jaw capping mechanism, when the bottle cap is tightened, if the capping head continues to apply force, the friction plate will slip, thereby preventing the bottle cap from being damaged and protecting the bottle cap. This mechanism adjusts the height of the capping head through a screw. Rotating the screw can change the position of the capping head, thereby meeting the capping and sealing requirements of bottles of different heights.
Q: How does the four-screw cap tightening mechanism drive the screw wrench to rotate to complete the cap tightening?
A: The motor of the four-screw cap tightening mechanism drives the worm and worm wheel to rotate through the small pulley, V-belt and large pulley, causing the vertical shaft to rotate. Meanwhile, the vertical shaft rotates clockwise driven by the sprocket, and the screw is installed on the vertical shaft of the cap tightening mechanism. The rotation of the vertical shaft will drive the screw to rotate together, and the upper pressing head will press the bottle cap under the action of the lever mechanism. The screw and the upper pressing head work together to finally tighten the four-screw cap onto the bottle or can.
From the perspective of the way of threaded connection, the sealing of bottles and cans is mainly divided into two types: multi-head threaded connection and single-head threaded connection. Take the commonly used bottles and cans for canned food packaging as an example. They are typical representatives of multi-head threaded connections. To facilitate consumers' opening, the sealing joint of this type of bottle or can will be processed with 3 to 4 threaded sections for connection. Each threaded section is approximately one-third the length of the entire circle of threads, with a relatively large lead, and the thread specifications follow general standards. The matching bottle cap will be designed with protruding claws corresponding to the number of threaded heads, and the inside is also lined with elastic rubber rings to further enhance the sealing effect.