Plastic İnjection Molding

Machine Training We will give information about plastic injection mold tooling in this article about mold and mold design. How the plastic injection machine works. We will examine the parts of the injection molding machine.

Plastic Injection Molding

Injection molding is not a continuous production method which is used in its own press, this method is mainly used only in case of mass production. In addition, special machines and special molds connected to these machines are used in this method. The machines used for this purpose have aspects similar to those used in the injection molding of metals. In spraying machines, spraying of liquid materials into the mold is generally provided by a piston. In many cases, however, presses working with an endless screw system are used, replacing piston presses over time.

Plastic Injection Molding Method

Special injection machines have been developed in order to prepare large volumes of liquid plastic and to flush directly into the mold at any desired time. This method is very similar to the casting of metals known for a long time. The injection molding machine consists essentially of a heating device with a piston inside which is used to melt the dispensing molding device and keep it at the desired temperature. 1- Outer mold half 4-Inner mold half 6-Injection plunger 7-Warehouse 8-Heater 9-Nozzle the molding means is filled into the funnel-shaped tank 7, which is mounted on the injection cylinder of the machine shown schematically. A nozzle (9) is disposed on the front of the cylinder, which is surrounded by heating elements (8). There are mold halves (1, 4) in front of the nozzle. When the piston (6) is pulled backwards, the mold opens automatically; When the piston moves forward, a pressure occurs and the mold closes immediately. In the forward movement of the piston, it is pressed into the mold with a certain amount of the molten material. The pressed material solidifies immediately as the mold is cooled. The solidified part is automatically extruded from the mold while the piston is retracted. This method of working is particularly good for thermoplastic materials but is a bit complicated.

Plastic Injection Molding Machines

In the above figure, the external appearance and parts of the plastic injection machine are given.

How does the injection molding machine work?

The following figure shows the parts of the injection molding machine. The working system of the plastic injection machine is described in the following section. These machines are similar to both the machine and the tool. Therefore, it would be useful to examine these machines together with the molds. In the above figure, a diagram of such equipment is shown. In the figure, the injection press and the cylinder are schematically described. The dynamic plate is driven by a double-jointed lever and cylinder tool. Both cylinders are hydraulically, the required hydraulic oil is pushed upwards through the oil pump (9,10) from the tank (12) and the spray cylinder (2), the closing bodies (8), the tap (11) and the adjustment tap (6) forwarded. The setting tap is a four-way valve, which can be actuated from both sides. The four-way valves are managed remotely, either electrically or hydraulically. the work cylinder (1) is usually operated in the same way. A camshaft is fitted in the system to stop the main motor of the press and remove the load of the entire hydraulic system.

How does the plastic injection method work?

The above section is in the picture; it is possible to see the approximate constructions of the single parts. This illustration shows the final status of the spray stage of the machine. The mold consisting essentially of the stationary part 21 and the dynamic upper part 23 is held in the closed position by the rotary pressure plate means with the stationary work table of the press. The melted article is sprayed into the mold cavity by means of the dispensing channels (19) from the spray nozzle (17). Before starting the pressing process, the artificial substance is filled from the hopper (9) into the spray cylinder (11) and the pressing piston (12) is moved forward, while the electric heater resistors (15) are supplied simultaneously. The heating is usually gradually increased in proportion to the increased pressure. The molding mass is distributed by uniform mixing with a torpedo (14) located in the middle of the machine. The torpedo is stationary in the cylinder 10. The liquefied device reaches the nozzle 5 by gaining a smooth flow rate in the torpedo. After the injection process, the mold is cooled by means of the cooling channels (2). The movable plate (1) is then brought to its initial position and the die is opened. The bridge (25) carrying the pusher pins is based on the pusher in the stationary position. The pusher pins 27 on the bridge extend to the mold cavity. With the help of these pins and the center pin (25), the sprayed workpiece is removed.