Process of blow molding products

Formation on the process of blow molding products made by the pressure is blown from the blower is commonly called blowpin, with air pressure between 5-8 bar.

Step-step process is part of the blow molding machine where raw materials (thermo plastic) which was originally converted into sleeve-shaped granules or parison. Postal 2 extruder continuously rotated by the motor of the post 3 after transmission through the post 4. Because round extruder, granule in hoper post a drop-down box, enter the barrel and pushed left by the round extruder. On a wall along the barrel heaters installed some post, where the barrel wall temperature is set more towards the front (left) until it reaches the higher melting temperature of the plastic. Plastics that have been driven melt flows into the die head post 6. At the end of the die head are heading pin 7 and 8 post Die, in which molten plastic flows through the gap between the pin and die. Because the gap between the pin and die Berpenampang ring, then after the material will pass through this slit-shaped sleeve post 9, a constant flow according to round extruder.

Oxtruder rotation speed can be set, as well as the size and the die can be changed to some extent.

This is to adjust the product to be dimolding kecilntya, and the short length of time eyele. The size and short length extruder and barrel, to determine discharge generated in the trenches every hour, which is not the same for each machine depending on engine class.

The amount of space or volume of the room from the area under the hoper, mid-length of extruder, extruder tip, inside the die head, until finally at the end of the pins & die, decreasing the volume of the room. With the decreasing volume of space, the plastic material inside the barrel until the tip of the die head having a compression or a higher compression. Therefore, the material is so ...... out of the tip of the pin and die where it has been free from compression, parison will swell. The amount of swelling is determined by the high and low levels of compression experienced. Further value of swelling is called the swelling factor and coded v.

For this type of material that is difficult "meeting" or difficult welding such as NylonPE, and PP, require a high-compression rate, so the swelling would be a big factor. Conversely, for the type of material that is easy retrieval such as PVC and PC requires a compression rate so low that the swelling factor is small. Both kinds of these properties must be known by the designer to be able to calculate the size of the pin and die, the width of the cutting, etc., when planning and toolingnya meblow mold.

Compression raises the temperature, the higher the compression rate the higher the temperature rise. Materials such as PVC having the nature of easy retrieval, but very sensitive to temperature, which is flammable. Conversely, materials such as PE and others difficult meeting, but more resistant to temperature. Therefore the type extrudor, die head, and the dimensions of the pin and the die must be adjusted at time of processing the material type of PVC or PE and others, according to the level of compression required.

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