JPS5937217B2 - Two-stage continuous kneading and extrusion equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-stage continuous kneading and extrusion apparatus that continuously performs melting, mixing, and extrusion molding (or granulation) of a polymeric material.

A conventional two-stage continuous kneading and extrusion apparatus is shown in FIG.

This two-stage continuous kneading and extrusion apparatus consisted of a continuous mixer 1 and a screw extruder 3 connected to this through a chute 2.

The continuous kneading machine 1 has a kneading cylinder 5 equipped with a hopper 4 for supplying raw materials, and a two-shaft kneading rotor 6 inserted into the kneading cylinder 5. The kneading rotor 6 is connected to a motor 7.
It is designed to be driven by a speed reducer 8.

There is a slot 9 on the tip side of the mixing cylinder 5 for adjusting the mixing degree.
is formed, and the molten resin whose kneading degree is adjusted by this slot 9 is discharged into the chute 2.

The screw type extrusion molding machine 3 has a cylinder 1 equipped with a heating device.
0 and a single screw 11 inserted into a cylinder 10, and the single screw 11 is driven by a motor 13 via a speed reducer 12.

A screen 14 and a die 15 are provided on the tip side of the cylinder 10.
An underwater cutter 16 for cutting the resin extruded from the die 15 is further provided in front of the cutter.

The resin raw material fed into the cylinder 5 of the continuous kneader 1 from the hopper 4 is melted and kneaded by the rotation of the rotor 6, the degree of kneading is adjusted by the opening degree of the slot 9, and it is turned into a rod-shaped molten resin and shot. 2.

The rod-shaped molten resin is supplied to a screw extruder 3, is given an extrusion force by a single screw 11, is extruded through a screen 14 and a die 15, is cut by an underwater cutter 16, and is granulated.

However, in the conventional two-stage continuous kneading and extrusion apparatus as described above, the extrusion pressure (50 to 250 kg/c111) required for extrusion in the screw extruder 3 was applied by rotating the single screw 11. , the ratio of the length to the diameter of the single screw 11 needs to be as large as 10 to 13, and the cylinder 10 needs to be able to withstand high extrusion pressure. However, as the size increases, the price increases, and extrusion consumes a large amount of energy.

The object of the present invention is to solve the above-mentioned problems in the conventional two-stage continuous kneading and extrusion device, and to obtain a two-stage continuous kneading and extrusion device that is small, inexpensive, and consumes less energy. It is.

Hereinafter, the present invention will be explained based on FIG. 2 of the accompanying drawings showing an embodiment thereof.

The two-stage continuous kneading and extrusion apparatus according to the present invention comprises a continuous kneading machine 21 and an extrusion molding apparatus 23 connected to the continuous kneading machine 21 via a chute 22.

The continuous mixer 21 has a kneading cylinder 25 equipped with a hopper 24 for supplying raw materials, and a two-shaft kneading rotor 26 inserted into the kneading cylinder 25.
6 is designed to be driven by a motor 27 via a reduction gear 28.

A slot 29 for adjusting the kneading degree is formed at the tip side of the mixing cylinder 25, and the molten resin whose kneading degree is adjusted by the slot 29 is discharged into the chute 22.

The extrusion molding device 23 includes a screw type extruder 30, a gear pump 31 connected to the extruding end of the extruder 30, and a gear pump 31.
It has a die 32 provided at the discharge part of the discharge part.

The screw extruder 30 has a cylinder 33 equipped with a heating device.
and a single-shaft screw 34 inserted into a cylinder 33, and the single-shaft screw 34 is driven by a motor 36 via a reduction gear 35.

The single screw 34 has a short length to diameter ratio of 4 to 6, and the cylinder 33 has a length of several kilometres.
The structure is such that it can withstand pressure of g/crit.

There are two gears 37 at the tip extrusion part of the screw extruder 30.
and 38 are provided, and the gear pump 31 is driven by a drive device (not shown) capable of variable speed operation.

A screen 39 and a die 32 are provided in front of the discharge portion of the gear pump 31, and an underwater cutter 40 for cutting the resin extruded from the die 32 is further provided in front of the screen 39 and die 32.

Next, the operation of the two-stage continuous kneading and extrusion apparatus according to the present invention having the above-mentioned configuration will be explained.

The resin raw material put into the cylinder 25 of the continuous mixer 21 from the hopper 24 is melted and melted by the rotation of the rotor 26.
The resin is kneaded, the degree of kneading is adjusted by the opening degree of the slot 29, and the molten resin is discharged into the chute 22 as a rod-shaped molten resin.

The rod-shaped molten resin is supplied to a screw extruder 30, and is forced out by a screw 34 to a gear pump 31 under pressure of about 9/crj.

Next, the molten resin is pumped by the gear pump 31 to
The extrusion pressure is increased to 0 kg/i, extruded through a screen 39 and die 32, cut by an underwater cutter 40, and granulated.

As explained above, according to the present invention, the extrusion molding device in a two-stage continuous kneading and extrusion device consisting of a continuous kneading machine and an extrusion molding device connected thereto via a chute can be replaced with a screw type extruder. Since it is composed of a gear pump connected to the extrusion section at the tip of the screw extruder and a die provided at the discharge section of the gear pump, the pressure at the extrusion section of the screw extruder can be reduced to several kg/cyyt. Therefore, the length of the screw can be reduced to 1/2 to 1/3 of that of the conventional screw, and the wall thickness of the cylinder can also be reduced.

In addition, the screw driving motor and speed reducer can also be downsized, and as a result, the extruder can be downsized and the cost can be reduced.

Therefore, the energy consumption of the extruder is significantly reduced, and can be reduced to 1/2 to 115 times that of conventional extruders.

Furthermore, since the shearing effect of the screw is reduced, an increase in resin temperature can be prevented, and a high quality resin can be obtained without deterioration of the physical properties of the resin.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional two-stage continuous kneading and extrusion device;
The figure is a sectional view of a two-stage continuous kneading and extrusion device according to the present invention. 21... Continuous kneading machine, 22... Chute, 23... Extrusion molding device, 30...
・Screw extruder, 31...Gear pump, 3
2...Die.

Claims (1)

[Claims] 1. A two-stage continuous kneading and extrusion device comprising a continuous mixing machine and an extrusion molding device connected thereto via a chute, wherein the extrusion molding device includes a screw type extruder and a screw type extruder. A two-stage continuous kneading and extrusion device characterized by having a gear pump connected to a tip extrusion section of an extruder, and a die provided at the gear pump discharge section.