DE2255473A1 - PROCESS FOR MANUFACTURING MULTI-LAYERED OBJECTS, IN PARTICULAR COVERING FOR ELECTRICAL CABLES - Google Patents

Description

9.11. 1972 IG / you

1. DAHTIGHINIPPOLT CABLES, LTD. :No. 8, ilishino-ChoJIigashi llukaijima, AmHgBSaICi-SlIiJiIyOgO, Japan »

2. HITSUBA MFG CO., LTD .: No. 1-1, Koyarna 5-Cliome, Shinagawa-Ku Tokyo, Japan.

Process for the production of multilayer articles, in particular Coatings for electric cables.

The invention relates to a method for producing multilayer Objects, in particular from 'coatings for electrical' see cables,

These are made with hardened rubber, plastic or with a multilayer Hose covered.

There is already known a method using hardening, where i is a. not hardened object hardened thereby is because / 3 he is in a bath of at atmospheric temperature high temperature, which has the following advantages compared to the known high pressure Danipf vulcanization process Has:

1j The equipment required is simple and 2) the work steps are relatively easy.

It is known to manufacture such a low pressure hardening process of .objects made of rubber or plastic tu KVJ ve na on,: <■ ;. ν ;. Door a / ensterrahinenpaclamg. However, it is still rjiclit egg. been used for the production of multi-layered Objects such as electrical cables that are sheathed with hardened materials or a hose, wolche Sjkw. which "has a multilayer structure".

Such hardened layers are necessary in order to be of high quality eIg-Ictrißciie or mechanical properties. For however, the low-pressure process has this purpose

.30983270m '

following reasons not been successful. 1) ¥ eil in a rubber or plastic öf'nn ^ ^ ene air or moisture nielit completely removed will ti can so that the Guiiuui obtained or the plastic remains porous. 2) Moisture and other volatile components in the grain or the im

(3 ·
Air present between the core and the coating layer is heated and expanded while hardening, which leads to the separation of the clad from the core.

In order to avoid the formation of pores in the product in the low-pressure process, a process is known in which calcium oxide is added to rubber or plastic in order to absorb moisture, otherwise bubbles will form. However, Dn, the compound except the 'Sonc'ht i;:' :. contains oit different volatile ingredients Calciu ioxyd ^v can not absorb, the known method does not prevent the formation of voids in the cured iurzeiignis which attributed to the volatiles ι ground, i £ ± n another method, voids avoid Zn, is a vented, a single spindle having extruder - '^ use, having a barrel with a vent hole, as can be described by OW Baumgarten, rubber and rubber, 1S ) (8), page ^ 9 ^ »19 ^ 6» But it has been found that this method is completely inadequate for the removal of moisture and volatile components that are present in rubber or plastic and that it is also difficult, produce multi-layered products, nisse with sufficiently large freedom from pores thereafter.

The aim of the invention is to provide a method for the production of multilayer articles, wherein a core with nicit hardened rubber or plastic is coated in layers, the core is heated and hardened by a heating material, ζ. Ϊ3. a molten eutectic mixture of inorganic Salting, takes place at atmospheric temperature.

Erf indugsgeniäß it is proposed that a first, uncured rubber or plastic compound in a vacuum

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Chamber is extruded with the aid of a first extruder, the extruded connection of this is lambted , lengthened or slit with the help of a cutting tool, the slit Vex-connection exerts a feed funnel, fed to a second extruder, the slit connection under reduced pressure is maintained, the connection with the aid of a second extruder, uki around a core is extruded which was getrOc'Oiet previously heated and that a curing svOri-ichtuiig. cloaked the core olme bending effect is zugefülirt which is maintained at elevated temperature in _s which is the uncured rubber or plastic jacket around the core, called and cured, using such first and second extruders that the sum of the ratio L / D of the first extruder and the ratio L / D of the second extruder does not exceed 2k . "".

.10 ^ 9832 / 0.824

An embodiment of the invention is shown in the drawing and is explained in more detail below «Show it;

Fig. 1 is a schematic arrangement of the components for the
Manufacturing process of a coated cable with hardened rubber or plastic sheath »

FIG. 2 shows a longitudinal section of an extruder E according to FIG. 1.

Fig. 3 is a longitudinal section of a cross head, dör with
a long-surface tool and is provided with a long-surface nozzle extension piece.

FIG. H is a section along line I of FIG. 3.

Fig. 5 is a longitudinal section of a hardening device according to the invention. .

FIG. 6 is a perspective view of the feeder shown in FIG.

Fig. 7 is a front side view of another Härtuiigs-Vi direction »

FIG. 8 shows a section along line II - II in FIG. 7.

Fig. 9 is a front side view of another example a hardening device

Flg. 1o a section along line III-III in FIG. 9.

It can be seen from Fig. 1 that a core W fed from the drum A is passed through the drying heater B before being fed to a cross head D of an extruder E, in FIG
which the core is completely dried, usually .ei
a temperature above 9o C. Then the dried core is passed through an additional heating device C, in which the core surface is heated, regularly at a temperature

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not lower than that which is So C below the hardening temperature. The heated core is immediately inserted into the crosshead D. As set forth below _g it "in detail followed by a treatment through Harlem in the hardening bath Fj .a optional Wasptten in the washing area G and wound onto a reel H. '■ ■' -

"■" - Jr.

For a person skilled in the art it is apparent that this method can be used effectively for coating any. Core material can be used ₀ Examples of core materials _} which are usually coated with plastic or rubber in a mass processj are electrical conductors, such as stranded bare conductors _t a with. a layer of a rubber jacket or plastic covered conductors, such ver · = litzte or woven strands or cables of a plurality of ^ insulated conductors with or without Jutefüllung ₀ This also includes hose nuclei, such as tubular bodies made of hardened rubber or plastic or the same, but multilayer body _s which may include a spring element between the layers ₀ Ss ersieht "borrowed, that many other core materials can use for this procedure. ·

The drying of the core in the drying apparatus B should be sufficient soda.6 _s when the core is heated during the subsequent Ileizvorganges, würdejg reduced the defects of the liberated from the core Gasos. ,, If the core insufficiently dried} in the device B If the core W is covered with a layer of rubber or plastic and is then introduced into the curing trough, so the dumbbell or the slat is caused by gases that arise between the core and the layer,

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solved or separated. - 6 - -

The drying time in the device B depends largely on various parameters such as the composition and eggs Size of the core or the drying temperature. For example, in the case of cores that contain a jute filling, the If it contains plenty of moisture or oil, this is the drying time unusual, d. H. 2 to 24 hours at 90 ° C or 40 minutes to 2 hours at 105 ° C or 5 to 10 minutes at 100 G. In the case when the head is made with hardened rubber or plastic is insulated, the drying time is 1 up to 3 hours at 90 ° ö, 20 minutes to 1 hour at 105 ° 0 and 1 to 5 minutes at 180 G. The higher the drying temperature of the core j, the shorter the drying time. There but an au. high drying temperature. Disintegration of The drying temperature should preferably be used not be more than 200 ° G. However, this value differs depending on the composition of the core.

If the drying time exceeds one hour, it is advisable to to dry the core batchwise instead of continuously as shown in FIG. The core can be below 90 ° G at a Temperature are predried, and this leads to a shortening of the drying time in the device B.

In connection with the invention, the following attempt used to check whether the core is sufficiently dry. A predetermined length, preferably one meter or more, the dried core is cut off, and the cut surfaces are immediately sealed at both ends. Then the

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2255471

Core heated for 30 minutes at 90 ° 0 and the weight loss of the core "not determined. If the weight loss more 'than 0.1 of the total weight of the fo Ee RNab cut it before the heating, a full drying will be accepted..

¥ / enn the surface temperature of the core, which is in the. Crosshead D enters, is low, can be between the core surface and air trapped in the rubber or plastic layer expand during hardening, which creates the risk of that the layer can be detached from the core. Preferably should therefore the core, at least on its surface ^, is heated to a temperature by an additional heating device C that is not lower than the temperature that is around 90 ° G, 'preferably around 60 ° C, below the curing temperature lies. ■

If the drying of the core in the device B is carried out at a high temperature, accordingly, if the core is completely dried.

net and the surface of the core rises to a temperature which is higher than the temperature, which is 90 C lower than the hardening temperature, is the Additional hardening of the core, not required by device G.

Drying apparatus B and the additional Trocknungsvorrich- · tung G could an individual per se known construction ^have: z. B. as a hot air dryer, infrared dryer or electrical ■ radiator. Hot, in particular dried air is preferably used, which is fed in continuously or in the

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Device circulates. The drying and the additional heating may be due to a temperature above the curing temperature Temperature, because the uncured layer is not yet present. The dried and heated to a high temperature Core W is then inserted into the cross head D when moisture absorption or temperature falls in Core can be expected before reaching the cross head D, a component is preferably used to prevent the reabsorption to avoid the humidity and the temperature drop at the core, like a hot air tunnel between devices G and D.

Core W is made from natural with an uncured compound or synthetic rubber or plastic or a mixture thereof. Different types of rubber and Plastics can be used and one of ordinary skill in the art will recognize such Materials according to the invention can apply as far as this can be ejttruded and heard ...

As an example of various rubber and plastic materials, which can be used according to the invention are the diene rubber, e.g. B. natural rubber, butadiene rubber, litrile rubber, Styrene butadiene rubber, polyisoprene rubber and the like, Polyolefins such as B, ethylene propylene, copolymers, ethylene « Propylene-diene terpolymers, polyethylene, ethylene-vinyl acetate, Ethylene-ethyl acrylate, butyl rubber and the like, halogenated Polymers such as B. chloropolyethylene, chlorosulfurous polyethylene, epichlorohydrin rubber, polychloroprene, chlorinated Butyl rubber, chromium-plated butyl rubber and the like, polysulphide

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rubbers such as thiol and the like; and inorganic polymers such as silicone rubber and the like. You can also, depending on Use mixtures of these compounds in individual cases.

It also requires no special reference to the fact that the 'uncured rubber or the plastic compound additives regularly' contains, depending on the application, _a .z example, fillers, pigments and the like. According to the invention, such additives are not new, but are commercially available, but can also be used in the invention. ^:

Look Pig. 2 describes how the uncured compound is extruded while moisture and others gaseous components are removed. The unhardened one Connection is made in the form of thin yarns, cords or the like in a rectangular vacuum chamber 3 with the help of the First extruder 1 extruded, which is provided with a screw, a screw or the like 13 and a breaking plate 12 is, whose front surface 11 to the vacuum chamber is facing. The extruded goods are immediately transferred to an in the vacuum chamber - existing rotating tool 2 slit open, which is located opposite the end face 11 of the plate 12. Tool 2 is attached to a rotating shaft 21, which extends through the wall 24 of the vacuum chamber 3. and is driven by a motor M via a belt 29 and a Pulley 26 driven. Shaft 21 is supported by a bearing supported, which is held by the side wall 24 of the vacuum chamber 3 by bolts. Bearing 23 is supported by an arm 27

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supported, which is attached to a (not shown) base part of the first extruder 1. It is a seal 35 available. The distance between cutting tool 2 and plate 12 can be changed by turning an adjusting screw 25, which is screwed into the rear end of the bearing 23, so that a projection 22 is moved, the on of the shaft 21 is present, or to withdraw the screw from the projection. By a pump, not shown, the Vacuum chamber 3 evacuated. The pump has an outlet opening 31 in connection. The pressure drop in the chamber 3 during work is indicated by a measuring element 33. The extruded cords are cut through a cutting tool cut into fine flakes as in knife 2, and the flakes fall on a feed roller or the like 42 on Bottom of chamber 3. Roller 42 conveys the flakes into a second extruder 4, which is connected to a screw or spindle 43, a crushing plate 45 and a cross head D is provided. Roller 42 or some other feed device in the feed section 41 of the second extruder effectively serves this purpose in particular to transport those flakes into the other extruder which tend to have a "bridge effect", i.e. H. in the feed room Form lumps or stick together.

The flakes adhere to the inner wall of the vacuum chamber 3. A Sheet 34 made of polytetrafluoroethylene attached to the inner surface the vacuum chamber 3, effectively serves to prevent such adhesion. Instead of this sheet, others can Process used to prevent the adhesion of rubber or

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Avoid plastic 2α, ζ. B. a sheet that .with. Silicone rubber is coated, or you use silicone oil instead of the polytetrafluoroethylene sheet. ·

During their stay in the vacuum chamber 3, the Flakes dried and degassed at lower brackets. That Drying and degassing is faster and more complete, when the thickness of the flakes is small, the ratio of the surface area to the volume of the flakes is large. However, the thickness is the flakes preferably no more than 4-0 microns, especially not more than 20 microns »The size of the vacuum in the vacuum chamber 3 is preferably as high as possible at a Ensure gates drying and degassing. Usually, the pressure in the chamber 3 is about 1 mmHg or less is used, preferably about 50 mmHg or less.

For most square materials, usually in an extrusion process In order to be used around the Eern, the residence time in the vacuum chamber is suitably chosen so that that it is between 0.5 and 20 seconds. Regularly this time will be about 2 to 10 seconds. For it will be apparent to one of ordinary skill in the art that the value these sizes can fluctuate greatly, especially upwards, and that various parameters, such as the size of the flakes, the level of vacuum, the size of the surface, etc., in suitable V / can be changed to allow the treatment in the vacuum chamber with different suitable times allow.

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Furthermore, in order to effectively degas and dry the flakes within a short time, it is important according to the invention to vigorously mix the compound in the first extruder. For this purpose it is preferably provided that the first Extruder has an L / D ratio (the ratio of the length of the screw to the inner diameter of the barrel (barrel, inner, diameter)) of at least 8, in particular in the range from 10 to 12 and a compression ratio (the ratio of the Kanalvoluniens of the feed section of the screw to the front end part of the screw) from 1.2 to 3

On the other hand, the second extruder only has the function of the flake-like rubber or the flake-like plastic to extrude, which was previously dried and degassed in rows. Hence the scorching of the compound in the heat to avoid the by mixing -ler connection through the Screws in the second extruder, the second extruder preferably has an L / D ratio as small as possible, usually from 4 to 10.

In the extruder E, the compound is subject to frictional heating because the knife 2 slits at high speed, in addition to the heat generated in the first and second extruders. Therefore, in order to avoid the scorching of the compound, it is necessary with respect to the extruder that the heat generated inside is decreased during the extrusion. In order to achieve this it is important that the sum of the L / D ratios of the first extruder and the second extruder

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is no greater than 24, preferably no more than 20.

I am individually known per se tool and · a. Nozzle. Or ", a neck nipple can be in the cross head of the second extruder be used.

Bs is not always necessary; within the. Nipp elans at ζ es during extrusion; of rubber or plastic on the core to be evacuated with a view to ensuring that the entry of Air between the core and the Sehiohtenmantel can be avoided ■ should, Evacuation is preferred because it is an extrusion material arises, which has a better connection between the core and its cladding. .

If a stranded core or a plurality of insulated conductors is coated with the extruded material as a jacket, the extruded jacket surface often becomes uneven because of the strands. You can prevent this unevenness by that you have a long-surface tool and a long-surface Kippel approach as in Fig. 3 is used.

Fig. 3 shows that the cross head D is provided with a long-faced Hippel shoulder 46 which is held by a holder 53, while the long tool 49 ^{is fixed to 1,} the housing 48 of the cross head by a tool holder 47, and it is a multi-way passage 50 between the housing 48 and the Kippelansatz 46, also a guide part 54 for the flow is present. Tool 49 is provided on the inner surface with a layer 51 made of polytetrafluoroethylene, and

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its relative position to the nipple neck 46 can be determined by 4 the Dioke adjusting screws 52 can be changed. If you use such a long-surface workpiece, the flow resistance becomes increased in it, likewise the pressure of the connection in the tool. Thus, the recessed part becomes W of the core is well filled with the compound, and a cladding layer W 2 is created that is free of unevenness the core W is as shown in FIG.

The backflow of the connection into the nipple approach is due to the uniform movement of the core W and the length of the Prevents nipple 46, whereby an increased backflow resistance is created. The required length of the elongated Tool depends on the viscosity of the connection and also increases with increasing viscosity. Usually the surface length is at least 15 mm, preferably at least 50 mm. On the other hand, the surface length of the long-surface nipple can be shorter if the viscosity of the Connection is large and when the feeding speed of the core is greater. In general, to the reflux too prevent the surface length of the nipple is preferably at least half the surface length of the tool.

After leaving the cross head B, the one with the uncured The core W provided with a connection is introduced into a hardening device F, see Fig. 1, while the core is rectilinear is, d. H. without significant bending, and in this the coating layer is heated and cured. According to the invention

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- 15 - ■ - ■ '■■ "-. ■" It is important that the coated core W should be introduced into the hardening bath in a straight line without excessive bending., while he gets from the cross head to the opening of the hardening bath. is if this is not the case, the uncured can. Mähtels chi cht, which is still deformable, deformed or bent or separated from the core and this reduces the quality, in particular the mechanical and electrical properties of the cured multi-layer product *.

Figures 5-10 show three typical hardness maps which ensure the introduction of the core of essentially straight lines.

As can be seen, the essential work step associated with the curing according to the invention is the temperature the non-hardened rubber or plastic layer To raise a temperature that is above the temperature of the decomposition point of the hardening liquid or the like and maintaining the originally uncured rubber or the like layer at "a temperature above that Maintains the decomposition temperature of the hardening liquid or the like for a sufficient time to complete the hardening *

The compound or liquid used for curing The purpose according to the invention and its amount are not so far decisive, d. H. any thermally decomposable hardening liquid or means, which is already known, is. around a rubber or plastic compound to hard, can be used in individually known amounts for the invention. Here

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It should be noted that the hardener should not be overly volatile should avoid its excessive loss during drying or extrusion under reduced pressure as well as the formation to avoid excessive pores in the cured rubber or plastic. In this context, it must be taken into account that while on the one hand preferred hardeners in the v / es entlichen are not at all volatile in the case of those used here Hardness are the same temperatures, on the other hand, highly volatile hardeners can be used insofar as they are not essential cause separation of the layer from the core or the formation of voids in the cladding layer. It can also depend on the respective instructions for use, which one To use harder is what the expert, depending on the individual case, recognizes.

Include various organic and / or inorganic hardeners which can be used according to the invention preferred hardeners include the following compounds:

1) The organic peroxides or mixtures of peroxides and sulfur or mixtures of peroxides and dioximers.

Examples of peroxides are: dicumyl peroxide, di-tertiary butyl peroxide, 1,1 di-tertiary butyl ^{I-Peroxyäthan} and 1,4-bis (tertiary butyl peroxy) -Diisopopylbenzol. Examples of dioximes are: p-quinone dioxime and p, p'-dibenzylquinone dioxime.

2) Thiuram, mixtures of thiuram and thiazole, mixtures from thiurax and imidazoline, mixtures of thiuram and lead oxide or mixtures of thiuram and dithiocarbamate. At-

, 30983270.824 ORfGINALtNSPiCTlD

- 17- ■ .. games for thiurams are: tetramethylthiuram monosulfide,

Tetramethylthiuram disulfide, dimethyldiphenylthiuram disulfide, Dipentamethylene thiuram monosulfide and dipentamethylene thiuram tetrasulfide. Examples of dithiocarbamates are: zinc dimethyldithiocarbamate, Zinc diethyl dithiocarbamate, selenium diethyl dithiocarbaiate and · tellurium diethylditniocarbamate. Examples of thiazoles are: 2-kercaptobünzothiazole, Dibenzothiazyl-Msulfid., Zinc salt of 2-EercaptoberizothiazQl and H-diethyl - 2-benzothiazyls. An example of imidazoline is 2-kercaptoimidazoline. - '

3) Mixtures of zinc oxide, liagnesium oxide and imidazoline like 2-l> lercaptoimidazoline.

4) Mixtures of the above dioximes with metal oxides "Examples of lethal oxides are: Eotes lead (Pb ₃ O ₄ ) and lead oxide (PbO)" ■

b) Sulfur or sulfur mixtures with the above thiuram. These hardeners and hardener mixtures are appropriately selected and coordinated in advance. with known methods, depending on the rubber or plastic base used.

The amount of hardener is selected in a manner known per se, is usually more than 0.1 fo, based on the weight of rubber or plastic, and the properties cannot regularly be improved if more than about 10 fo, based based on the basis weight. ^{For the 'Fachmarm:} ' it can be seen that the effect of the hardener varies and "larger and smaller values, depending on the individual case, can be used with success."

The hardener or hardeners are usually not the- • r ^ .m- ;: · · \ ~ . *> 309832 / 082Λ

-1ο ~

cured compound is added prior to treatment, and this can be done in a manner known per se, usually if the hardener or hardeners are added to the .Uligehärteten compound at the same time as all the desired additives.

In some cases a compound hardener is used; H. a hardener that breaks down at different temperatures. At gradually applied temperatures to preferred To achieve effects. Such types of proceedings are individual known per se and are not described here.

It can be seen that the hardener or hardeners do not disintegrate and that hardening at a certain level does not occur during the extrusion of the unhardened rubber or plastic, d. H. the extrusion takes place in time at a temperature below the hardening temperature.

In connection with the invention, heating fuels can be of various Kind used that; However, they are not allowed to react significantly with the layer and the temperature during the Hardening must not increase so that disintegration occurs. Such "heating fuels are known per se and their selection is in this respect not critical for the invention.

The heating materials can be .Liquids such as organic liquids, with a boiling point higher than;> 00 ⁰ G, preferably above 350 ° C, e.g. B. polyglycols, silicone oils, mineral oils and "the like molten eutectic mixtures of inorganic salts, e.g. mixtures of KtiO-, IMaNC, - and HaKO.j etc.,

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- 19 molten eutectic mixtures of metals like a Mixture of $ 42 tin and 58 ^ bismuth, hot air according to Japanese Patent application for “19714/1969 un <3- a fluid bed according to Japanese patent application Mr. 26561/1963. Optional can heat be supplied by ultrasound, compare the magazine "Kautschuk und G-uiami-Kuiiststof fe", Vol. 22 12, Page 717 (1969). -

Regardless of the type of fuel, it is of course necessary to that the one provided with the unhardened compound Core is introduced into the hardening bath (the term hardening bath is used in the application to mean that it represents the area in which the uncured jacket layer comes into contact with the heating material. In the following examples, on the other hand, the term hardening bath is used to denote a liquid heating medium to designate with 'which the core or core and cladding layer comes into contact). .

In order to facilitate the treatment and to reduce the cost and maintenance of the apparatus, it is useful as Hardening bath to use a heatable liquid. The examples contain preferred embodiments, however, can ir: Kahn en d ^ r invention also an equivalent heating fuel. be used as the meaning of the hardening bath in the general sense is to allow the hardener disintegrates or is transformed into a state in which the Hardening can be done at elevated temperature.

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From this it can be seen that the treatment time in the hardener apparatus can vary significantly and is not critical as long as the necessary curing occurs. With the preferred Systems consisting of a core and a core sheath are hardened using the Hassen method, but in less than half an hour generally by less than 10 minutes. On the other hand, in mass production, there will be no reason to go faster than to cure in 20 seconds and possibly this time is half a minute to about 10 minutes according to practice the invention.

In the hardening bath, FIGS. 7 and 8 (hardening apparatus II), core W provided with the non-hardened layer passes through the opening 63 in the upper hardening trough 60 in this trough, which is arranged above a lower tray 61. On the outside wall of the trough 61 · fastened supports 62 carry the trough. the The surface of the layer and its immediately adjacent parts are heated and hardened by the liquid hardener 64 in the upper trough 60 at atmospheric pressure is brought to an elevated temperature. After the core had left the upper trough 60 through opening 65, it will The lower hardening trough 61 is fed via a rotating wheel 70. Wheel 60 is provided with a shaft 92 in the rear Area of the outlet 65 is arranged, with part of the wheel in the liquid 64 within the lower Hardening trough 61 is immersed, and the core is heated again by the liquid 64 in the lower trough. Then he will back into the upper trough 60 through another opening 68

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introduced with the aid of a rotating wheel 67. This wheel has a shaft 92 around which the wheel rotates, the Shaft is located at the opposite end of the trough relative to the rotating wheel 66, and the core is heated for the third time, The layer is now completely cured. Of the Core leaves the upper hardening trough 60 via opening 69.

The liquid in both the upper and lower hardening troughs is kept at a temperature that is usually is about 150 to 250 ° 0, by means of an electrical heating unit 70.

When using most heating materials, whether liquid, solid or gaseous, hardening is carried out at 150 - 250 ° 0 with a preferred one Range from 170 - 230 C. With one the lower limit If the temperature is below 150 ° C, hardening takes a longer time, while with one the upper temperature Temperature exceeding the limit, higher than 250 ° G, some types of rubber and plastic disintegrate. The inside of the Above range temperature allows expediently, the curing time with regard to. the danger of To compensate for decay, and at this temperature, effective handling is easily maintained.

After the surface layer of the jacket has hardened vigorously is, the core can be bent without deformation and separation of the clad. That constantly from the inlets 63 and 68 and outlets 65 and 69 of the The fuel flowing out of the upper trough descends into the lower one

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Hardening trough down, and the fuel in the upper hardening trough

is adequately replaced by the substance that is from the lower
Trough via pump 72 and line 91 is promoted.

In the hardening bath according to FIGS. 9 and 10 (hardening apparatus III), a horizontal, rotating wheel 73 is used which is immersed in the liquid and is present in the lower trough instead of the rotating wheel 67 of apparatus II. Here, core W is set in circulation by the wheel 73 and again the lower one
Hardening bath supplied. Then the core leaves the lower hardening trough via a pair of guide grooves 74. These guide * -
Wheels can be moved to any desired position of the hardening bath in order to adjust the hardening time for the core, if necessary.

The apparatus shown in Fig. 5 and 6 (apparatus I) has a trough. Two vertically movable plates 77 are arranged in a pair of guides 76 which are attached to the side wall 71 of the hardening trough. Each plate has a semicircular cutout 78 to define an inlet 63 or an outlet 65. Liquid flowing down through the inlet 63 and the outlet 65 is received in a receptacle 79 which is present on both sides of the trough and is then collected in a basin 82 which has a heating unit 81 with guide pipes 88. The collected in basin 82
Substance is heated by the heater 81 and returned by the pump 72 to the hardening trough 60 via a temperature control device 82 which regulates or regulates the temperature of the substance.
checked.

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The fuel suitable according to the invention is a liquid, z. B. a molten eutectic mixture of inorganic salts, molten eutectic mixture of Metals, or an organic liquid with a high boiling point, d. H. one above the hardening temperature, preferably with a boiling point above 300 ° 0. Further, a fluidized bed can also be used as a fuel.

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As shown in Fig. 1, W, whose coat layer is cured has been, the washing device G, where from this layer the heating material adhering to the surface is removed. For example, washing the core can be done by immersing it in a washing liquid which is capable of dissolving light heating fuel, or a liquid detergent is sprayed on. To get washing liquid to save and reduce the amount of wasted fuel adhering to the layer can a squeezing device made of cotton, silicone foam gununi and the like Exit of the hardening trough or immediately after it. Most of the adhering to the surface of the layer Fuel is removed by the squeezing device while the core is withdrawn from the trough. Used If a molten eutectic mixture of inorganic salts is used as the fuel, the jacket layer is preferred Washed with warm water at around 60 C and also higher because a eutectic mixture is easily mixed in by dissolving warm water can be eliminated. The removal of the substance is more complete when using warm water from the core and brushing the surface with a suitable brush, or the core while washing with liquid by ultra-frequency excited.

The washed core is wound up immediately on the reel or after cooling, if appropriate. In the following Examples, comparative examples, which do not restrict the subject matter of the invention to those specified there Individual values and the like are intended to mean, data relate to parts and percentages by weight, unless otherwise stated.

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2255475

- 25 Example 1 .. '-

The machine for making electric winding wire; according to this example has a drying cylinder with air circulation of a length of 20 m, the internal temperature

is kept at 11 ο C and the electrically heated. Cylinder has a length of 2 m, the internal temperature of which has been kept at 18o G. The extruder cross head received a temperature of 90 ° C. and the loading device I, 20 m long, was replaced by a molten eutectic mixture of 53 / £ KNO "". 7 fo NaNO ", ^ o <fi> NaNO ₂ (percent by weight) filled and kept at 200 ° C. This eutectic melts at iko C,

Three electrical wires, each of which has an insulating layer 1.2 mm made of natural rubber are twisted together, stranded or the like, with the help of jute, and on the outer surface of the A cotton tape was wrapped around the stranded material to form a core which had an outside diameter of 10.3 mm. Then the core was passed through the above device at a speed of 1 m / min. Natural rubber

t ι

According to compound X in Table 1, the length of the core was increased extruded so that its outer diameter became 13 »1 mm when used an extruder according to FIG. 2, which contained a first extruder, the screw or screw thereof L / D ratio of 12 and a compression ratio of 1.5 had, with a cylinder, the inner diameter of which was 90 mm, while ^ a second extruder is a screw or screw had, its L / D ratio 8, its corapression ratio 1.5 and a cylinder with an inner diameter of 70 mm; was used. The vacuum chamber had a rotating knife

309832/0824

- 26 with h cutting. The cans of the first and second extruders

were adjusted to temperatures of 60 C or 7 ο C.

The knife rotated at a speed of 1,700 rpm and the joint to be machined was 3o microns thick Slashed flakes. The inside of the vacuum chamber was kept at 60 3gmm.

The core made with natural rubber according to compound I after extrusion was inserted into the hardening trough without bending between the extrusion device and the Hardening trough was approved, and was pulled out of the hardening trough with the help of a guide wire that was 5 m away from the inlet of the hardening trough (the effective hardening time was 5 min., the effective length of the hardening trough is 5m),

The temperature prevailing at the core before entering the cross head was measured with the aid of a copper constantan thermocouple measured, which was inserted about 1mm deep into the surface of the core. The temperature was determined to be 178 ° C.

After hardening became the heating fuel that was on the surface of the Layer was left, cored by washing with water. The electrical wire obtained, completely covered with "hardened" Natural rubber was free from porosity and could be used for 5 hours. can be continuously produced for a long time without difficulties,

Examples 2-6 and see Examples 1-2.

The electrical wires in Examples 2-6 and the

309832/0824

Original

- 27 similar examples 1-2 were made using Cores and the apparatus given in Table 2. The manufacturing conditions and results according to these examples or the comparative examples are also shown in Table 2.

The curing time for each example was set so that dsß the coated core from the trough with the help of the guide wheel deducted \ rarde that was placed in a position xirelche the allowed to adhere to the desired hardening time.

According to Examples 3, 5 and 6, the core was dried while it was being wound on a drum or reel.

309832/0824 -

Table 1

Substance / compounds

Substance / Substance / Substance / Compound Compound I formation II formation III (for sheathing (for sheathing (for sheathing) insulation))

Components (in parts)

Haturl. Rubber (belly sheet No. 2, specific weight, 0.91; Mooney viscosity, 50 (ML _{1 Α> (} at 100 ⁰ C))

Polychloroprene (M-40, product of Denki Kagaku Co., Ltd., specific gravity 1.23 ^ weight; Mooney viscosity 42 (ML _{1 + 4} at 100 ⁰ C)) toÄthylen-propylene-diene terpolymer (Hordel 1040, EI du Pont de ⁰⁰ ITemours & Co., Spec, weight, 0.86-0.87; Mooney viscosity, 40 lbs (ICL _{1 + 4} at 100 ⁰ C))

^ Hard clay (Dixie clay, specific weight, 2.62; specific heat, 0.20; aqueous content less than 5 %; ignition loss 13.4 Ή ¹ ^ talc (specific weight, 2.7; specific heat , 0.207)

Carbon black (FEF carbon black, specific gravity, 1.7-1.9; pH, 7.5; particle diameter, 40 m | 0

Carbon black (HAF carbon black, specific gravity, 1.7-1.9; pH, 8.1; particle diameter, 30 nm)

Stearic acid (mp, 69.3 ⁰ C; specific weight, 0.85); Zinc oxide (specific weight, 5.5)
- paraffin (mp, 50 ⁰ C; specific gravity, 0.88). I tetramethyl-thiuram disulfide
£ ► Aldol-oG-naphthylamine
O llagnesiun oxide (ignition loss, 8.61 fo)

. Processing oil (specific gravity, 0.937; aniline point, 95.7; viscosity (SVS, sec.Tr 90 98.9 ¹³ C and 2200 at 37,8- ¹⁰ C)

100

50

100 100

30th _ - _ 2 - 4th _ IS9 10 - 4th - 2 U * 10 25th - 5 - CJI
-P- 2 1 - -4 5 5 5 3 2

15th

table 1 (continued)

Fabric / ties

Components (in ropes)

2-Hercaptiimidazoline Dicumyl Peroxide

c * i sulfur ο

CD,

Fabric / yerbin

manure I (for

mante-

lung)

Material/
Yeroin

manure II
(for um-

mante-

lung)

q, 7

Fabric / connection III (for insulation)

2.7 0.3

Table 2

Work step no.
Wire core

Length of the heating drying cylinder B in m conditions for heating and drying the core County {* e of the additional heating cylinder C in m Zsizbedingungen thereby

Core surface temperature immediately before entry in cien cross head (= extrusion head) connection for the coating, extruded onto the core Conditions for the extrusion of the coating compound

L / D ratio

1. Extruder pressure ratio

Case temperature (C)

Rotating knife speed (rpm) Thickness of carved flakes (microns) Vacuum level of the vacuum chamber (mml-lgj

L / D ratio

2. Extruder compression ratio

Case temperature (C) Crosshead temperature D (C)

Example 2

A core with an outside diameter of 18.4 mm, formed by stranding of free conductors (each of which has an insulating layer made of hardened natural rubber 1.2 mm thick) with a jute filler, after which a cotton tape is wrapped around the stranded core will.

85 120 ° C χ 15 minutes

6 200 ° C x 1 minute

183 V »

Compound II ^

15th

1.2 00 240

23

50

Sr I

1.2 6o 90

to

Table 2 (continued)

Outside diameter of the coated wire (mm) 21.8

Type of hardening tube and its effective length * (m) Type-I, 13.8

Hardening conditions (same liquid as in Example 1) 2oo ° G χ 2.5 minutes

Core speed (m / min.) 5.5

Remarks . Wire coated with hardened

to

ο pore-free and bubble-free layer

to - ■■. '. ■

oo ■. could - for a period of time

can be made within 1 hour.

OO

IS3,

F-

! ΪΝ9 cm

Table 2 (continued) Example 3

Core, 6.0 mm in diameter, formed by stranding three conductors, each of which has a hardened layer made of natural rubber.

Drying in batches 9ο ⁰ C χ 3ο minutes

ο ¹ ' ² 2οο C χ 1ο seconds

136

Connection- II 12

8ο

43οο 17 2ο

5ο 9ο

Example 4

Core, with an outer diameter of 6.00 mm, formed by strands of 7 copper conductors from 2, o mm to each other,

14ο C χ 2 minutes

135

Connection- III 12

7ο

39οο 15 βο

8 2

1 ⁷ ο ° ο

Example 5

Core with an outside diameter of 7.2 mm by stranding a number of copper conductors and by softening a paper tape around the stranded copper conductor.

Drying in batches at 130 ° C 10 minutes

128

Connection- II 15

1.2

80

32 00

35

2o

5o 9o

! Table 2 (continued)

15.0 i · 8.4 Type-II, 29.2 Eyp-II, 66.0 180 ⁰ C χ 4 minutes 190 ⁰ C χ 3 Wed 7.3 22.0 Same as in example 2 Same as i 30 983 2, ^v ο
00

11.8

Eyp-II, 86.5 180 ⁰ C 3.5 minutes

24.7 Same as in example 2

K) CJl

Table 2 (continued)

Example 6 Same as in example 2, equivalent example 1 same as in example 5

Comparative Example 2 Same as in Example 2

u> ο to

"> v O OO

Drying in batches at 12o ° C χ 40 minutes

120 fabric / binding II

15th

1.2 60

240

23

50

1.2 60 75 130 ⁰ C 5 minutes

130 substance / compound II

1.2 80

3200 35 20 12 2 50

25 Fabric / Compound II

15th

1.2 60

240

23

50

1.2 60

aa

C4>

90 90

90

labeile 2 (continued)

21.9

Type-I, 15.8 200 ⁰ Cx 2.5 minutes 5.5

11.8

Ϊνρ-Ι, 51.5 180 ⁰ C χ 3.5 minutes

14.7

A wire covered with a charring started about 10 minutes hardened Shift that are free after the start of operations and

of pores is, however, one

became excessive after 30 minutes

slight separation of the layer strong. The case was closed

from the core shows.

represents.

21.8

ÜJyp-I, 13.8 200 ⁰ G x 2.5 minutes 5.5

The coating broke at various points along the product because a. there was increased pressure between the cladding and the core. This pressure goes to gas formation back because the IrocknoiiEi's work ride omitted.

Claims (1)

Claims Process for the production of multi-layered products, in particular electrical cables and the like, using rubber or plastic as the layer material which is hardened at low, e.g. atmospheric pressure, characterized in that a non-hardened rubber or plastic compound in a vacuum chamber by a first Extruder is extruded, then the size of the extruded material is reduced in this chamber by a cutting tool, the cut material is fed to a second extruder while maintaining a reduced pressure in the cut material, then the material is extruded around a core through the second extruder is, the core being dried and heated prior to the second extrusion, then the coated one. Core is fed substantially straight and without significant bending of a hardening device, in which the coated core is brought into contact with a heating fuel, and the temperature of the non overall ^1-cured rubber or a plastic compound is increased, so that the uncured rubber - or the plastic layer around the core is heated and cured at a pressure essentially corresponding to atmospheric pressure. 309832/0824 2. The method according to claim 1, characterized in that before the extrusion of the not yet cured rubber or plastic ^{compound, the core is heated to at least one: temperature of 90 0} C, and that at least die.Kernfläche is kept at a temperature that is not lower than the temperature which is 90 ^° C. below the hardening temperature. 3. The method according to claim · 2, characterized in that »that. at least the core surface is kept at a temperature which is not lower than the temperature which is 60 ^° C. lower than the hardening temperature. 4. The method according to claim 1, characterized in that the first extruder has an L / D ratio of at least 8. 5. The method according to claim 1, characterized in that the Rubber or plastic goods leaving the first extruder in the vacuum chamber is slit to a thickness of at least 40 microns or less; d. 6. The method according to claim 1, characterized in that in a pressure of about 100 mmHg or less is maintained in the vacuum chamber. . ■ 7. Method according to claim 1, 'characterized in that the inner wall of the vacuum chamber coated with a material which has no adhesion properties, properties relative to has slit rubber or plastic material, 30983270824 8. The method according to claim 7, characterized in that for this purpose polytetrafluoroethylene is used. 9. The method according to claim 1, wherein the slit rubber or plastic _{material is fed to this inlet with the aid of a feed device at the} inlet end of the second extruder. 10. The method according to claim 1, characterized in that the cross head of the second extruder with a long-surface tool is provided, the length of which is preferably at least 25 mm. 11. The method according to claim 1, characterized in that the The cross head of the second extruder is provided with a long nipple, a nipple attachment or a sleeve-like component, whose wall length is preferably at least 25 mm. 12. The method according to claim 1, characterized in that the hardening device is a hardening bath, the liquid heating fuel is maintained at a temperature of about 150 to 25O ⁰ G. 13. The method according to claim 12, characterized in that this fuel is a molten eutectic mixture inorganic salts is. 14. The method according to claim 12, characterized in that this fuel is a molten eutectic mixture Metals. 309832/0824 15. Procedure according to. .Claim. 12, characterized in that ' this fuel is an organic liquid whose boiling point is above the hardening temperature. 16. The method according to claim 1, characterized in that the Hardening device containing a liquid heating material Has trough that the core covered with an uncured rubber or plastic compound through the second extruder into this trough through one in the side wall of the trough arranged inlet opening is introduced into the trough, wherein the fuel flows out of the inlet and in a collecting basin is recorded. 17. The method according to .Anspruch 1, characterized in that a The hardening trough can be placed higher, one hardening trough lower, both can be provided with a liquid heating fuel, and the with a rubber or plastic compound that has not yet hardened the covered core is first fed to the upper trough by the second extruder via an opening in the side wall, then transported horizontally and in a straight line in the upper trough while the core is in contact with the fuel, it is then removed from the upper trough via one in the Wall of the latter existing opening led out and then introduced into the lower trough below the upper trough, in particular via a rotating wheel or the like. is introduced. 18. The method according to claim 17, characterized in that the fuel flowing from the inlet of the upper trough falling into the lower trough and that the fabric 309832/0824 of the lower trough is fed to the upper trough in the circuit, 19. Terfahren according to claim 17, wherein the with a rubber or The core covered by the plastic coating is also passed horizontally through the heating material in the lower trough and then fed back to the upper trough will. 20. Terfahren according to claim 17, characterized in that the core covered with a rubber or plastic compound after its horizontal transport through the lower trough as well as through the fuel located there is in turn passed through the fuel of the lower trough. 21. Terfahren according to claim 12, characterized in that a liquefied pesticide is used as heating fuel. 22. Terfahren according to claim 13, characterized in that the coated, hardened in a molten eutectic mixture of inorganic salts core is ^{washed in warm water at a temperature of not less than Go 0} C, such that the surface of the hardened layer remaining salts are washed out. 23. Terfahren according to claim 22, characterized in that the from remaining salts can be removed by brushing with the help of e.g. rotating brushes. 24. Terfahren according to claim 22, characterized in that the remaining 'salts are removed by ultrasonic excitation of the goods 309832/082 / » will. 25. The method according to claim 1, characterized in that as Fuel heating gas is used. 26. The method according to claim 1, characterized in that the heating is carried out by ultrasound irradiation. 27. The method according to claim. 1, characterized in that the Rubber or plastic compound itself contains a hardener. 30 9832/082 4 Blank page