Principle of single screw extrude

2016-12-20

Ordinary single-screw extruder is composed of three systems; Transmission system, extruding system and heating cooling system.

(a) transmission system, the system room for extruder drive power, generally by the motor and deceleration into a unit

Extrusion system 1 (2) charging device including hopper and automatic feeding device 2 cylinder is also called the barrel because of plastic under high temperature and high pressure inside cylinder manufacturing materials to be used for cylinder high strength strong wear-resisting corrosion resistance of the alloy just 3 is the heart of the extruder screw conveying solid plastic plasticizing plastic transport an important part of a melting body is divided into three sections of both loading compressed paragraphs metering section Charging period is compaction plastic and conveying solid plastic compression chamber melt metering section of U.S.A plastic is to make further plasticizing uniform melting body and makes the material flow quantitative uniform flow from the extrusion of constant pressure

Heating (3) the heating system is composed of heating coil heating up by - 50 degrees of space for the cylinder and the material of friction heat up SJ series single screw extruder is mainly for extrusion soft and hard polyvinyl chloride, polyethylene, thermoplastics, it with the corresponding auxiliary (including forming the nose), for processing a variety of plastic products, such as film, pipe, plate, ribbons, etc., can also be used to make plastics extruder advanced design, high quality, good plasticizing, low energy consumption, involute gear transmission, low noise, smooth operation, large loading, long life and other characteristics.

SJ series single screw extruder design concept:

When in high speed on the basis of high quality, high yield.

Does the design concept of plasticizing at low temperature, to ensure high quality products.

Have two cascade overall design, strengthen the function of plasticizing, guarantee high performance out of adjustment.

Have special barrier, BM comprehensive mixed design, to ensure that the material mixing effect.

High torque output, large thrust bearing.

For high strength alloy steel gear, axis, carburizing, grinding processing.

Have high hardness, high smoothness and low noise.

PLC intelligent control, you can realize linkage between the main auxiliary machinery.

It was not easy to monitor the human-machine interface, easy to understand processing and machine status.

Not according to the need to replace control mode (temperature control table).

When the material is 38 crmoal/A nitriding treatment, wear-resisting.

Have strict temperature control precision, combination of air cooling water cooling.

Have unique design of into the mouth with perfect water cooling device.

When groove feeding bottom surface set of screw barrel, has enhanced feed functions, guarantee for the high speed and high yield extrusion.

Single screw extruder parameters

Single screw extruder is one of the plastics extrusion line, its technical parameters and models are as follows:

1, single screw extruder technical parameters:

1) extruder production capacity Q: the amount of plastic extrusion per hour

2) than the flow per hour per week extruder production capacity

3) the nominal power Processing kg plastic motor power needed for an hour

4) screw length to diameter ratio L/Db: working parts of screw length and the screw diameter ratio

5) screw diameter Db: refers to the large diameter, a series of standard 20, 30, 45, 65, 90, 65, 150, 165, 200, 250, 300

6) drive screw motor power P: KW

7) the screw rotation speed range: nmin - nmax r/min

2, model SL - 150 indicates the screw diameter of 150 mm, length to diameter ratio systematically plastic extrusion principle of single screw extruder

1. The mouth finally a thread started calling feeding period Material can't plasticizing here; but to preheating, squeezing the reality, the past old extrusion theory is that the material is loose, then by showing that the material is solid, that is to say here after squeezed a solid material like the plug, so as long as the delivery task is the function of it.

2. The second paragraph that when compression section of screw grough by gradually decreases, and the temperature to achieve the plasticizing degree of compressed by the delivery period of three here, compressed into a here, this is called screw compression ratio of 3:1, some machines also have change, complete the plasticizing material into the third paragraph.

3. The third section is the metering section Material maintain plasticizing temperature here, just like metering pump, accurate and quantitative transport, melt materials supply to the nose, the plasticizing temperature, the temperature cannot under general slightly high. High-speed single-screw extruder main use pipe extrusion: suitable for pp-r pipe, PE gas pipe, PEX crosslinking, aluminous model multiple tube, ABS pipe, PVC pipe, HDPE silicon core pipe and all kinds of co-extrusion composite tube. Plate and sheet extrusion: suitable for PVC, PET, PS, PP, PC board profile and extrusion. Other all kinds of plastic extrusion, such as wire, rod, etc. Profiles extrusion: adjust the screw extruder rotation speed and changing the structure can be applied to the production of PVC, polyolefins, etc. Various kinds of plastic different profile. Modified granulation: suitable for all kinds of plastic blending, modification, the increase of granulation.


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