JPS592829A - Continuous pressure vulcanizer - Google Patents

Abstract

PURPOSE:To provide the titled apparatus which can reduce the time of raising the temperature up to the vulcanization temperature of an extruded product and shorten the vulcanization line by building up of a temperature raising zone of a pressure vulcanization tube with a material with a small dielectric loss to be positioned in an applicator of a microwave dielectric heater. CONSTITUTION:A first pressure vulcanization tube 3 directly connected to a cross head 2 of extruders 1 and 1A made of ceramics, glass or the like small in the dielectric loss. The vulcanization tube 3 is wound with a heating coil 6 of a high frequency induction heater 5 and the subsequent zone of raising temperature of work W is positioned in an applicator 8 of a microwave induction heater 7. The work W is pressurized by an saturated steam outside while supported with a mandrel 12 inside to prevent initial foaming and hence, a double layer hose can be obtained with a greater adhesion force between the inner and outer layers.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a pressure vulcanization tube through which the extrudate can be passed in a state in which a pressurized liquid is sealed in order to continuously pressure vulcanize the extrudate such as rubber or elastomer. It relates to a device placed in front of an extruder.

Rubber extrudates such as multilayer hoses are desirably vulcanized continuously under pressure in order to prevent initial foaming and improve interlayer adhesion. This continuous pressure vulcanization is generally carried out with a liquid seal on the exit side so that saturated steam pressurized to t~/g kgf/c++t can pass through the extrudate as liquid. The pressure vulcanization tube was directly connected to the extrusion head of the extruder. However, in this method, since the material (rubber) with low thermal conductivity was heated only from the surface side, it took time for the extrudate to rise to the vulcanization temperature. Therefore, there is a limit to the improvement in productivity of extrudates, and it is also necessary to lengthen the vulcanization line.

In view of the above, the present invention provides a continuous pressure vulcanization device that shortens the time required to raise the temperature of extrudates to the vulcanization temperature, improves the productivity of extrudates, and shortens the vulcanization line. The purpose is to provide.

In the continuous pressure vulcanization apparatus of the present invention, the extrudate heating area of the pressure vulcanization tube through which the extrudate can pass in a state where the pressurized fluid is sealed is formed of a material with small dielectric loss, and The above object is achieved by placing it within the applicator of a microwave dielectric heater.

Hereinafter, one embodiment of the present invention will be described based on illustrated examples.

Here, we will explain using a two-layer hose as an example, but electric wires,
Of course, it is also applicable to extruded products such as weather strips and trims.

As shown in Fig. 1, the cross head 2vc of the extruder/J/A is directly connected to the first pressure vulcanization pipe 3, and the first pressure vulcanization pipe 3Vc is connected to the second pressure vulcanization pipe II. ing. 1st
The pressure-vulcanized tube 3 is made of a material with small dielectric loss, such as ceramics or glass. In addition, the first pressure vulcanization pipe 3
is wrapped around the heating coil 6 of the high-frequency induction heater S,
The subsequent extrudate heating zone is located in the applicator g' of the microwave dielectric heater 7 (see FIG. 2). The second pressure-vulcanized tube l is usually a steel tube covered with a heat insulating material, and a liquid sealer 9 is connected to the tip. Also, 1st and 2nd
The filling of saturated steam (pressurized liquid) into the Caropressure vulcanization tubes 3 and 1 is carried out from a boiler (not shown) through one supply pipe 10. reel,
12 is a mandrel for preventing the hollow part of the extrudate from being blocked, 13 is a microwave oscillator, and 11 is a waveguide.

The extrudate W extruded in two layers from the extruder 1 onto the mandrel/2 is
While being pressurized with saturated steam in the first pressure vulcanization tube 3,
The temperature of the applicator g (extrudate heating area) is increased by dielectric heating. At this time, the mandrel 7.2 has been heated in advance by the heating coil B, and the outside of the extrudate W is also surrounded by high-temperature saturated steam, so the extrudate W is at the vulcanization temperature (around 200°C). The current rises efficiently in a short period of time. Further, since the outside of the extrudate W is not pressurized with saturated steam and the inside is supported by the mandrel 12, initial foaming is prevented and the interlayer adhesion between the inner layer and the outer layer is improved. Subsequently, the extrudate W heated to the vulcanization temperature is passed through the second pressure vulcanization tube t.
After being held at the vulcanization temperature for a predetermined time to complete vulcanization, it passes through the liquid sealer 9 and is drawn out into the atmosphere. This extrudate W is then extracted from the mandrel 12 and cut into a product (a two-layer hose).

In the above embodiment, a high frequency induction heater was used to heat the core metal, but of course this is not necessary in the case of an extrudate having no hollow portion. Pressurized fluids are not limited to saturated steam;
An inert gas such as Nt may be used, and hot air may be used if the extrudate has no risk of ignition.

Since the continuous pressure vulcanization apparatus of this invention has the above-described configuration, it is possible to efficiently raise the temperature of the extrudate to the vulcanization temperature in a short time while pressurizing it, thereby significantly increasing the productivity of the extrudate. The vulcanization line can also be shortened.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view showing an example of a continuous pressure vulcanization line of the present invention, and FIG. 2 is an enlarged sectional view of the microwave dielectric heating portion in FIG. 1. /, /A... Extruder, 3... First pressure vulcanization tube, 7.
...Microwave dielectric heater, Za...Applicator, W
...-extrudate. Patent application Patent attorney Ii 1) Akio

Claims (1)

[Claims] In an apparatus for continuous pressure vulcanization by disposing a pressure vulcanization tube in front of an extruder through which the extrudate can pass while enclosing a pressurized fluid, the extrudate rises in the pressure vulcanization tube. A continuous pressure vulcanization device comprising a warm zone formed of a material with low dielectric loss and located within an applicator of a microwave dielectric heater.