(1) in the design of extruded plastic bottles, if the material is high-density polyethylene or polypropylene, the cross-section of the plastic bottle should be rectangular or oval, for the material of low-density polyethylene or other flexible plastic bottles, the cross-section of the circular as well. This facilitates the content to be extruded from the plastic bottle. The plastic parts used in conjunction with the plastic bottle are mainly caps and seals. Plastic bottle mouth design should focus on how to make plastic bottle mouth better with the lid and the sealing device. The bottom of the plastic bottle is a weak part of the mechanical properties of the plastic bottle. Therefore, the bottom of the plastic bottle is generally designed into concave shape, the corner of the plastic bottle, and the inner recess, do a large arc over.In order to facilitate the stacking of plastic bottles, increase the stacking stability of plastic bottles, the bottom of the plastic bottle should be designed within the groove.
(2) plastic bottle surface with the label, should make the standard veneer flat. A "frame" can be designed on the surface of the plastic bottle, so that the stickers are positioned accurately and do not produce movement. During blow molding, the first contact area of the parison is always tending to be hardened. So the wall thickness of the site is also larger. The Edge and the corner position, is the type billet blows the last contact the place, the area wall thickness is small. Therefore, the edges and corners of the plastic bottle should be designed as rounded corners. Change the surface shape of the plastic bottle, such as the middle of the plastic bottle is relatively small, increase the plastic bottle surface of the circumferential groove or convex rib, can improve the rigidity and flexural resistance of the plastic bottle.longitudinal grooves or stiffeners eliminate the displacement, sagging or deformation of plastic bottles under long-term load.
(3) The printing surface of the plastic bottle is the most concentrated part of the consumer's attention. Printing surface should be flat, continuous, if the plastic bottle contains a handle, groove, reinforcing ribs and other structures, design should be careful not to the printing operation caused inconvenience. The oval plastic bottle, the rigidity is also high, but the mold manufacture expense is high.Therefore, in order to ensure the stiffness of plastic bottles, in addition to the selection of high stiffness of the material, but also through the plastic bottle shape design, enhance the plastic bottle stiffness and load resistance strength.
(4) Because most plastic has notch sensitivity, plastic bottle at the sharp corner, the root of the mouth thread, neck and other parts, prone to crack and cracking phenomenon, so these parts should be designed to fillet. For the transfer of rectangular plastic bottles, it is necessary to support most of the load of plastic bottles, so local increase of the wall thickness, but also conducive to improving the plastic bottle stiffness and load resistance.