Pet Bottle Preform Shape Characteristics

At present, the shape of the preform of the pet bottle has a circular shape, a square shape, an elliptical shape and the like. The round bottle has the largest amount of use, and is characterized by a relatively uniform wall thickness, high ability to absorb impact energy, and low production cost, but low utilization rate of effective area during storage or transportation. When the square or rectangular bottle is stored, the effective area is highly utilized and the stability is good, but the swelling phenomenon is more likely to occur. The size of Pet Bottle Preform has not yet been clearly defined, and is usually based on the nature of the user's needs. In addition to the nominal capacity, the pet bottle has a full capacity, which is larger than the nominal capacity. The specific requirements are determined by the diameter of the bottle and the height of the bottle. Let us take the small and medium pet bottle as an example, and analyze the structural characteristics from the pet bottle mouth, the bottle neck, the bottle shoulder, the bottle body and the bottom of the bottle. Bottle structure characteristics For pet bottles for tablets and capsules, the design of the diameter of the bottle mouth mainly considers the individual volume of the articles to be loaded plus the appropriate space, which not only meets the needs of mechanical equipment, but also is convenient for people to use. The cross-section of the thread shape at the neck of the pet is mostly semi-circular, and is viewed from the outside as a fine thread at both ends. There are also trapezoidal threads, called single-head threads. The design of the neck-and-neck thread form mainly depends on the good compatibility with the cap, because the moisture-proof performance of the package depends largely on the tightness of the neck and the cap after the torque is applied. This is the main part that reflects the excellent sealing performance of the bottle mouth. After the pet bottle is loaded, the capping machine with adjustable torque should be used to screw the cap. The torque can be selected according to the relevant standard and the diameter of the cap. The size of the bottle and the cover is an important prerequisite for moisture resistance, and the tightness of the screw cap is the key to the effectiveness of the moisture barrier. In order to ensure the safety of the article, it is first necessary to improve the sealing of the bottle mouth portion and increase the moisture blocking effect. At present, the PET bottle mouth is made of aluminum foil gasket electromagnetic induction sealing, and the bottle cap is mostly made of anti-theft cover. The anti-theft cover provides visible traces to the seal failure, and is primarily constructed with small holes around the bottom of the bottle cover to form a break line. Bottleneck and bottle shoulder structure The shape of the pet bottle adopts a round bottle body, and the bottle body section is longitudinally dissected. The bottle neck and the bottle shoulder are composed of two tangent arc radii, and are divided into two stages of the truncated cone rotation body from the tangent point. The design needs to calculate the distance between the bottleneck and the centerline (radius), the shoulder radius, the radius of the neck arc, and the total height of the bottle neck and the shoulder of the bottle. The main factor affecting the strength of the shoulder is the inclination angle of the shoulder. When the shoulder is too flat, the bottle is prone to collapse. Therefore, when the shoulder length is 10 mm, the shoulder inclination angle should exceed 15 degrees. The thickness should not be less than 1 mm to ensure that the bottle does not have shoulder rupture during the loading and storage of the article and during use. Bottle structure characteristics The bottle body is a cylindrical circular body. The bottle body is required to have a uniform wall thickness. If the bottle wall is too thick, the weight of the bottle body will increase, the raw material consumption will increase, and the stress in the bottle body will increase, and the shrinkage amount will also increase. The bottle wall is too thin to be blow molded and has low strength. The general requirement is that the wall thickness of the other parts should be uniform except that the ribs and threaded parts at the bottle mouth are larger than the thickness of the bottle body. In order to improve the barrier and strength of the pet bottle, the thickness of the bottle body is generally 1.2-1.5 mm, and there is a tendency to thicken. Bottle bottom structure At present, the bottom of the pet bottle preform is designed with a convex bottom or a flat bottom, and the double rounded structure is mostly. The convex bottom, that is, the center of the bottom of the bottle protrudes into the bottle to form an arch hole, which can enhance the internal pressure resistance of the bottle body and ensure the stability of the bottle body. It can also prevent pet from collapsing during blow molding and can make the thickness of the bottom of the bottle uniform. The flat bottom double-rounded bottom structure is mostly suitable for large-volume bottles, which can better withstand internal pressure.        Welcome to contact Jilian Plastics, we have a full range of pet products, no matter what your needs, we can meet you. Our 5-Gallon Pet Preform have been favored and loved by many consumers in the market, so welcome to contact us.