The most common shapes of medicinal pet bottles are round, square, oval and so on. From the point of view of use, they each have their own advantages and disadvantages. Round pet bottles have a high stiffness but are not aesthetically pleasing. The square pet bottle has a beautiful appearance, but it is not easy to control the uniform thickness of the pet bottle during molding. The oval pet bottle has a higher rigidity, but the Pet Bottle Mould has a higher manufacturing cost. Therefore, in order to ensure the rigidity of the pet bottle, in addition to selecting the material with high rigidity, the shape of the pet bottle is also designed to enhance the rigidity and load resistance of the pet bottle.
Change the surface shape of the pet bottle, such as the middle of the pet bottle is relatively thin, increase the circumferential groove or rib of the surface of the pet bottle, can improve the rigidity and bending resistance of the pet bottle. Longitudinal grooves or ribs eliminate the offset, sagging or deformation of the pet bottle under long-term load. When designing a squeeze pet bottle, if the material is high density polyethylene or polypropylene, the pet bottle should have a rectangular or elliptical cross section. For low density polyethylene or other flexible pet bottles, the cross section is round. Shaped as good.
This facilitates the extrusion of the contents from the pet bottle. In order to make the pet bottle wall thickness uniform, it should be noted that the shape of the pet bottle should be symmetrical. Minimize extreme stretching points and parts. Arc transitions are used at all transitions. The printed surface of the pet bottle is the most concentrated part of the consumer’s attention. The printing surface should be flat and continuous; if the pet bottle contains handles, grooves, ribs, etc., the design should be careful not to cause inconvenience to the printing operation. When the surface of the pet bottle is marked with a label, the surface of the label should be flat.
A “sash” can be designed on the surface of the pet bottle to make the label accurately positioned without moving. At the time of blow molding, the portion where the parison inflates first contacts always tends to be hardened first. Therefore, the wall thickness of this part is also larger. The edge and the corner portion are the portions where the parison inflates the last contact, and the wall thickness of the portion is small.
Therefore, the edges and horns of the Pet Bottle Preform should be designed to be rounded. Since most pets have notch sensitivity, pet bottles are prone to cracks and cracks at sharp corners, roots of the mouth threads, necks, etc., so these parts should be designed to be rounded.