The process is similar to injection moulding and extrusion. With ldpe, the plastic industry growth rapidly1942the first polyethylene bottle was manufactured using the blow molding process1950the demand for blow moulding increases by the mass production of high density polyethylene hdpe and polypropylene pp for various applications. Process of blow moulding have the effects on bottle weight, bottle dimensions and machine output. Our moulding facility in the three manufacturing locations comprises a total of 182 injection moulding units with various clamping capacities ranging from 18 to 1200 tons, as well as 7 blow moulding units with capacities ranging from 200 to 750 cc. Extrusion blow molding guidebook blow molding advisors at apex.
At apex, we use a process called continuous extrusion blow molding to turn raw plastic into highquality finished products for our customers. Ideal for smaller plastic bottles, the injection blow moulding process can be used to mould a wide variety of polymers including pet and hdpe. Blow molding is the process of manufacturing hollow containers like bottles, jerry cans, jars, drums, tanks etc. The example shown below is of the production of a plastic bottle.
Injection and blow moulding yeakin plastic industry pte ltd. If more than one material is needed, a multibarrel machine is. Injection molding is one of the main methods by which parts are manufactured from plastic. Blow molding moulding is a specific manufacturing process by which hollow plastic parts are formed and can be joined together. In the blow molding plastic manufacturing process, plastic is heated until molten. Extrusion blow molding process is slightly different than injection blow molding process. Pdf the complete injection molding process dominic. The injection machine is constructed of a mold clamping device that opens and closes the mold tool, and.
Uniloys core technologies include urs reciprocating series blow molding machines, industrial blow molding machines, uai accumulator head, and uci. A typical extrusion blow molding process is shown in fig. The pet bottle blow moulding process works by reheating a premoulded pet preform which is then automatically positioned into a mould. Injection blow moulding is used for the production of hollow objects in large quantities. There are several different types of blow moulding.
Injection blow molding is the process whereby the plastic preform is injection molded and the preform travels on the core rod to the blow mold station, where blow air enters through the core rod and lifts the hot preform material off the core rod and forms it by air pressure to the design of the female blow mold. Blow molding is a manufacturing process that is used to create hollow plastic parts by inflating a heated plastic tube until it fills a mold and forms the desired shape. An outstanding and thorough presentation of the complete field of plastics processing. Blow molding modified extrusion and injection molding processes extrusion blow molding small tube is first extruded, usually vertically, then clamped and air blown inside to expand it to fit a much larger diameter mold air pressures 350700 kpa 50100 psi can be a continuous process corrugated pipe and tubing.
Blow molding is the manufacturing process by which hollow plastic parts like bottles and containers are formed. The parison is a tubelike piece of plastic with a hole in one end through which compressed air can pass. A plastic tube is heated up preparing to be inflated by gush of hot air. Pdf parameter study of stretchblow moulding process of. Extrusion blow moulding by opening the mould, the finished product is ejected. The most common blow moulded plastic resins are hdpe, ldpe, pvc, pet, pp etc. The basic process is to heat up the raw material to a molten state and blowing to the shape of cavity of the mould by air pressure. Extrusion blow molding blow moulding and injection.
Pet bottles are typically created using one of the three blow molding processes listed below. The liquid, molten plastic is injected into a cold mold. The most popular techniques in plastic molding are rotational molding, injection molding, blow molding, compression molding, extrusion molding, and thermoforming. Conclusion blow moulding is a manufacturing process for production of hollowform plastic products. In the stretch blow molding sbm process, the plastic.
The blow molding process begins with melting down the plastic and forming it into a parison or in the case of injection and injection stretch blow moulding isb a preform. The first step in the extrusion blow molding manufacturing process is the extrusion of a tube, also called a parison, of viscous plastic into a product mold. Manufacturing is in an environmentally controlled atmosphere, employing spc and sqc techniques ensuring highly. The types of molding processes are based on the type of plastics we use. Guide to polyolefin blow molding, contains general information concerning materials. The injection blow moulding process produces bottles of superior visual and dimensional quality compared to extrusion blow moulding. Once the plastic has cooled, the bottle is removed and the process repeats. In this process, the polymer is plasticized in a standard extruder and screw assembly. Blow molding is the process used to make hollow, plastic products such as containers or bottles. In 1961, flambeau added blow molding to their capabilities.
Compressed air forces the plastic outward into the shape of the mold. These plastic products or parts are created by extruding a tube of hot plastic, called a parison, into an open mold. The first production machines and products are developed in 1930 to manufacture blow moulded bottles. Injection moulding injection moulding handbook spritzguss handbuch njection moulding handbook spritzguss handbuch njection moulding. Well cover all these techniques in this guide to help you discover the best process to make your part or product. The blow moulding process is similar to glassblowing process. Pdf blow molding modified extrusion and injectionmolding. If you blow air into a plastic tube that is closed on all sides except the point at which the air enters, the tube will. That is, the filling shortage is caused due to the extension of molding cycle and slow filling rate. Chapter 2 injection moulding process injection moulding is the most widely used polymeric fabrication process. The first step in the injection molding process is to feed plastic pellets into the hopper, which then feeds the pellets into the barrel. Once the plastics is cooled, the plastic is ejected from mould.
Blow molding is a process used for making hollow objects such as piping or milk bottles. Blow molding process is used for which has thin wall sections. Blow molding is defined as a plastic process whereby a thermoplastic material is heated to its forming temperature, which is below that of the plastic materials. High pressure food grade compressed air is then injected into the preform which expands to form the shape of the mould. Guide to extrusion blow molding i contents list of contributors 6 contents i introduction 1 1.
The main applications are bottles, jars and other containers. Blow molding pgoduces bia ial orient ati o n greatly figure 46 twostage reheat blow molding. Extrusion blow molding process regency plastics, gemini. If a higher polish, lower friction, or longer wear is desired, nickel ptfe coatings such as polyond7 or nicklon8 can be used. The video shows the process of blow moulding compression moulding. Compression molding process,injection molding, blow. The process is ideal for both narrow and widemouthed containers and produces them fully. As we know that there are two types of plastics, one is thermoplastics and the other is thermosetting plastics and depending upon the nature of plastics, molding process is divided into 4 types note. The blow molding process begins with melting down the plastic and forming it into a parison or in the case of injection. The parison is placed within a split mold with a hollow cavity. In this thesis, blow mould design is to be done for a. Injection blow moulding is used in the production of large quantities of hollow plastic objects.
Later, the hot air pushes and expand the plastic against the mould to form the desired mould shapes. Blow molding explained manufacturing solutions group. At the side where the capacity is small, plasticizing time and injection time become long, and it is used at the narrow capacity of the molding machine. The blow moulding process, in comparison with injection moulding, is a low pressure process with typical blow air pressures around 25 to 150 psi. Extrusion blow moulding process is a framing process of a bladdery product by blowing a thermoplastic liquid tube called a parison fit as a fiddle of a mould hole. Injection blow molding an overview sciencedirect topics. Flambeau now has over 100 blow molding machines ranging in size from 1 to 40 pound shot in its facilities around the world. Practical guide to blow moulding pdf free download epdf. Its a critical industrial process for making onepiece hollow plastic parts with thin walls, such as bottles and containers.
Injection blow moulding the uks leading plastic trade. Blow molding process apex plastics extrusion blow molding. The barrel is heated and contains a reciprocating screw or a ram injector. The plastic is fed in granular form into a hopper that stores it. It is also used for forming glass bottles or other hollow shapes in general, there are three main types of blow molding. After the introducing of low and high density polyethylene which is suitable for blow moulding the market is hiked for blow moulding products. The mold closes around the parison and air is pumped in to. Uniloy is a global leader in blow molding technologies and the only blow molding machine manufacturer to offer four unique blow molding technologies as well as blow molds and associated tooling.
Extrusion blow molding ebm is the oldest of the various blow molding processes. The process of injection blow molding ibm is used for the production of hollow glass and plastic objects in large quantities. Blow molding experts valencia plastics custom blow molding. The raw material in this process is a thermoplastic in the form of small pellets or granules, which is first melted and formed into a hollow tube, called the parison. Handbook of plastic processes is the only comprehensive reference covering not just one, but all major processes used to produce plastic productshelping designers and manufacturers in selecting the best process for a given product while enabling users to better. Blow molding is a process in which manufacturers use air pressure to inflate soft plastic into a mold cavity. Computer integrated manufacturing cim in extrusion blow molding. A simple guide to plastic molding processes, best uses.