Jiangsu Victor machinery co., LTD ZengDiao
The bottle is a can be placed in the container, liquid or solid can be found everywhere in our life, medicine bottles, cosmetics bottles, beverage bottles everywhere.
Due to the rapid development of petroleum industry, human invented the polymer or plastic, from now on our material by a single glass or ceramic bottle into a wide variety of plastic.
Reference has a long history of glass blowing process, will be in viscoelastic state extrusion or injection molding of plastic type embryo in blow molding mold, through certain pressure of compressed air to embryo huff, close to the cavity wall, cooling stereotypes demoulding after get consistent with the cavity shape of hollow plastic products.
This is the familiar hollow blow molding process.
Hollow blow molding
Hollow blow molding is a kind of rapid development of plastic processing method, has now developed into a plastic bottle of the first mode of production.
Hollow blow molding has the advantage that the mold and mold costs are low, rich mold material;
Can produce hollow shape of complex products, there are wide development prospects;
It can produce large hollow products;
Development speed, the plastic products in the first group;
Production efficiency and high automation.
Disadvantages include the product shape has certain restrictions;
Wall thickness control to have certain difficulty;
Dimension precision is low.
Common blow molding process are extrusion blow molding, blow molding and injection stretch blow molding.
Extrusion blow molding, extrusion plastic melt by extrusion device, extrusion type embryo implantation after blowing in blow molding mold, cooling stereotypes after stripping out products;
Injection blow molding, injection type out a bottom embryo first, and then transferred to the blow molding mold blowing, cooling stereotypes after stripping out products;
Stretch blow molding, extrusion or injection production embryo, in blow molding mold with tensile axial tensile rod and transverse stretching after blowing cooling stereotypes, the stripping out products.
Crowded blowing and injection
Extrusion blow molding is one of the biggest blow molding method, are also blow molding method appeared earlier, suitable for PE, PP, PVC, PETG, thermoplastic engineering plastics, thermoplastic elastomer and other polymers and various blend of blow moulding, is mainly used to produce packaging containers, storage tanks, and other industrial parts.
Extrusion blow molding is first and foremost by type extruder extrusion tube embryo, material since the nose after plasticizing extruder melting extrusion;
Then type embryo clamping and mould, when the embryo reaches the predetermined length, intercepting a tube embryo strike to be put in blow molding mold, closed mold, clamping at the same time;
After blowing type embryo, the compressed air blowing through the mouth into embryo, type embryo blowing into the exact shape of cavity are;
At last, the mould to take out the products.
Blow molding and injection molding is combined by injection molding and blow molding a blow molding method.
First use of injection molding production zone at the end of type embryo, and then type embryos transferred to the blow molding mold for blow molding.
Injection blow molding first is production-oriented embryo, injection will melt with injection blowing air core tube with bottom type developed in the injection molding of embryo, and then through mechanical device to blow blow molding in the location of the blow molding mold;
After blowing type embryo, blowing mold mold closing, the compressed air by the core porosity type imported into the embryo, embryo in air pressure and blow molding cavity fit closely, after cooling to the demoulding location;
Final product release, at the top of the demoulding location from the products on the mandrel will be out off or directly to the packing station, and then into the next cycle process production.
The advantages and disadvantages compared
Crowded blowing technology is suitable for all kinds of plastic material, type embryo through the nose with low pressure and blowing pressure, equipment and mold cost is relatively low, the container of the production cost is low;
Can produce multilayer, thin wall and complex container capacity ranging from 1 ml to 3000 l, widely used in packaging, building materials, household appliances, food, machinery, automobile and other fields.
Into production process will produce flash, however, need to secondary recycling;
Bottle mouth, the teeth size is not stable, poor sealing;
Automation is poorer;
Product cycle is long, the production efficiency is low, it is the defects of blowing process.
Injection process automation depth of the injection and production efficiency is higher;
Good molding products, the quality of the extrusion blow molding;
At the bottom of the products without the stitching line, high strength, uniform wall thickness, the mouth size precision is high;
No marginal waste, or flash, joint line fine;
Container is suitable for processing small batch big refining and jar containers such as cosmetics, daily necessities, medicine, and food packing bottle.
Downside of injection process, can’t in processing complicated shape of the products;
Container capacity limits in 5 ml to 500 ml.
With our common on the market 100 ml bottle of lactic acid bacteria used as a reference, can be found: crowded blowing of lactic acid bacteria at the bottom of the bottle have crowded blowing process of flash and cut marks, unable to meet the demand of customer together, the bottle wall thickness uniformity is poorer, bottle parts have different wall thickness, strength is low, there is a certain risk of leakage;
And injection of lactic acid bacteria at the bottom of the smooth, with no flash and cut marks, can meet the needs of customers are together, the bottle wall thickness uniformity, the position of the bottle is due to injection molding, precise size, high strength, no shrink phenomenon, can satisfy the demand of seal easily, more high-grade
PK crowded blowing blowing process
Thus found the injection and extrusion blow in the production of the same kind of products, injection has inherent advantages, no flash, no waste, size accurate, injection of the three-stage method to high production efficiency at the same time, the three stations operate at the same time, without gap.
Cooperate with conveyor belt, testing equipment can be directly into the packaging location, high degree of automation.
Thus may draw a conclusion: in the packing bottle range to use, adopt injection process to produce the bottle can improve production efficiency and reduce the production cost.
By darth vader machinery co., LTD., jiangsu MSZ model of the production, for example, equipped with professional injection system and precision control system, to satisfy the high speed, high clamping force and combining a model mould each location clamping force uniform distribution requirements, sod rotary lifting system can be 120 ° rotation, three station can make injection molding, blow molding and stripping continuous smooth running.
At the same time due to the use of hydraulic linkage, makes the model more accurate positioning, lower maintenance costs, and more quickly.
Demoulding location with conveyor belt to realize automatic stripping, automatic counting and automatic packaging, the entire process to avoid the hand touching, makes the machine production of the products can meet the requirements in the field of medicine and health care.
The two characteristics of extrusion blow molding process
Parison wall thickness controller, no core design
In these two techniques, crowded blowing in the production of thin wall products, complex shape tubular or bottles have obvious advantages
Parison wall thickness controller in the parison forming stage, according to the parts in the parison swell when the blow ratio, which can adjust the parison wall thickness distribution.
At the same time, considering the parison formation extrusion expansion, sagging and springback of the changes, to produce the reasonable degree of parison thickness distribution curve, and then adjust the electro-hydraulic servo system, make the mouth die clearance between the die and die changes over the parison position, uniform thickness of blow molding products.
Products resistance to impact experiments show that the wall thickness uniformity makes products on strength had the very big enhancement;
Also save raw materials, shorten the cooling time of the finished product, and reduce the defect rate, greatly improving the production efficiency and product quality.
In automobile industrial fittings, for example, car doors, car roof, have common WuFengMen high-end car handles
Because of the crowded blowing technology to produce products, frivolous, high strength, can meet the demand of the car is an, reduce fuel consumption, reduces the manufacturing cost more. So the way hollow blow molding automobile accessories application more and more, such as fuel tank, all kinds of pipe fittings production, etc
No core design, shine brilliantly in the domestic cosmetic
With common large supermarket common cosmetic volume, automobile maintenance such as large volume bottles, for example. Because of the large bottles, large volume, heavy quality, customers will give preference to the bottle with handle in the process of choosing products daily taking and using convenience.
Due to no core design, need not consider demoulding screens, crowded blowing structure can produce attached handle. Even structure more complex products collapsible containers etc.
Crowded blowing big PK injection application