DE2310388A1 - Contact heating device - for heating plastics tubes and profiles to elastic-deformation temperature - Google Patents

Abstract

In a contact heating device which is in design similar to a press, plastics-coated holding jaws are provided which snugly fit the tube or profile to be heated. The plastics coating is applied only at the surfaces coming into contact with the tubes or profiles, and an electric heating device is embedded in the holding jaws in close vicinity to the contact surfaces. The claimed device affords direct contact of the plastics article with the heating surfaces without risk of caking or thermal degradation.

Description

Contact heaters for plastic pipes The invention relates on a contact heater to warn plastic pipes and profiles on a Temperature at which these tubes and profiles can be elastically deformed.

Devices are already known in which Ro'ure and Profiles be brought into an elastically deformable state by heating. These well-known Devices consist of double-walled ones with oil or heating bands or heating cartridges directly heated containers, the shape of which is the plastic pipe or. Profile shape of the to processed object are adapted and a certain distance and thus a Have air cushions between the plastic part and the heating surface. The disadvantage of this hitherto known heating device consists in it.

that there is direct contact between the components to be heated and the irritating surfaces do not exist, as the plastic parts immediately upon contact would stick to the heating surface and thus be destroyed.

The object of the present invention is to provide a simple, To create an electrically heated contact heater with which it is possible to use plastic pipes and to bring profiles to a temperature at which they can be elastically deformed, without these parts being attacked.

This is achieved in that in this press-like design Contact heater adapted to the pipe, profile shape and pipe and profile diameter, the plastic tube or profile to be heated erg enclosing at the contact surfaces with the tube or profile plastic-coated jaw half attachable ind, in embedded in an electrical heating device adjacent to the contact surfaces is.

This is done with little effort by the arrangement of the electrical Heating device near the contact surfaces and through the plastic coating flawless electrical heating of the pipes and profiles is possible on these surfaces. This means that these pipes and profiles are brought to a certain temperature can, in which these tubes and profiles are elastically deformable without this Bake on the contact surfaces.

According to a further embodiment of the invention, this contact heater a plastic tube that can be moved in at the same time as the jaw halves are closed, plastic-coated mandrel on, in which the contact surfaces are also adjacent an electric heater is embedded.

This enables the heating-up time, especially in the case of plastic pipes to shorten by evenly heating the plastic pipe from the inside will.

According to a further embodiment of the invention are in immediate Proximity of the contact surfaces to a corresponding one Test column temperature-dependent Test means, e.g. 3. Thermocouples attached to control the heater.

This allows the electrical heating device in a simple manner can be controlled in such a way that the contact surfaces always have a uniform temperature is broadcast.

According to a further embodiment of the invention, there is the electrical Heating device consisting of several heating cartridges, which cover the entire contact surface evenly surround.

This ensures that the heat is evenly distributed over the entire area Contact surface ensured, so that the elastic deformability of the to Machining dell plastic pipes and plastic profiles as identically as possible at every point is.

In the drawing are those necessary for an understanding of the invention Details shown.

Based on this drawing is an embodiment of the invention described.

1 with the press-like contact heater is designated. In the embodiment, a plastic tube 8 is shown, which when you close the Jaw halves 2 and 3 comes into contact with these. There are heating cartridges in the halves of the stream 4 and 5 embedded. The representation is only symbolic.

Likewise, it is only shown symbolically that the contact surfaces of the jaws, which come into contact with the plastic pipes or profiles, a plastic layer Exhibit it.

A mandrel 6, in which heating cartridges are also embedded, can be introduced into the tube are. The mandrel is also plastic-coated 7 on its contact surface 8 in order to achieve a Avoid caking of the pipes.

The heating cartridges are embedded adjacent to the contact surfaces, in order to reduce the temperature of the contact surfaces with the lowest possible power to bring the desired height.

The contact device is designed so that when pipes are heated and closing the jaws, the mandrel is automatically inserted into the pipe to be processed will.

If profile shapes are heated instead of pipes, they are accordingly insert other jaws adapted to the profile shape into the contact heater.

A conversion of the heating device to a different Ronx diameter or another profile shape is special here due to the interchangeability of the heating jaws simple.

In that the electrical heating device consists of several evenly Cartridges distributed over the entire contact area are also uniform Warming of the basement area ensured.

Bn one or more points of the contact surfaces can be temperature-dependent Test equipment, e.g. thermocouples, attached in the immediate vicinity of the contact surfaces which one of the controls provided for this purpose determines the temperature of the contact surface indicates, so that by means of this test means an automatic control of the heating device possible it. In this way, the temperature of the contact surface can be approximately the same being held.

With the arrangement described above, not only is the warm-up time shortened, but also in heating power and thus saved in electricity.

The contact heating device described can be used in a simple manner in the operating process area can be set up without great effort, so that continuous production is guaranteed can be. In this way, both the subsequent pressing and upsetting in the exact shape as well as bringing it to the exact length thereby ensured, that the contact heater is arranged as expediently as possible in relation to this device can, i.e. without being exposed to the risk of the pipe or profile being damaged prematurely comes out of the elastically deformable state.

Claims (4)

Claims 1. / Contact heater for heating plastic pipes and profiles to a temperature at which these tubes and profiles can be elastically deformed, d a d u r c h g e k e n n n z e i c h n e t that in this press-like trained Contact heater (1) adapted to the pipe, profile shape and pipe and profile diameter, closely enclosing the plastic pipe or profile to be heated at the contact surfaces Jaw halves (2, 3) coated with plastic with the tube or profile can be attached in which an electrical heating device (4, 5) is embedded, 2. Contact heater according to claim 1, d a d u r c h g e k e n It should be noted that this contact heater (1) is on at the same time as it closes of the jaw halves (2, 3) in a plastic-coated plastic tube that can be moved in Has mandrel (8) in which the contact surfaces adjacent an electrical heating device is embedded. 3. Contact heater according to claim 1 or 2, d a d u r c h g e k e n n z e i n e t that in the immediate vicinity of the contact surfaces on a corresponding Test center for temperature-dependent test equipment, see B. Thermocouples, for control purposes the heating device (4, 5, 7) are attached. 4. Contact heater according to claim 1 or 2, d a d u r c h g e k e It is noted that the electrical heating device (4, 5, 7) each off consists of several heating cartridges, which evenly surround the entire contact surface.