DE1640890C - Process for the production of a conductor insulation - Google Patents

Description

·; ιlassid bearer protected. Beir.i processing such Tapes then come later, especially when in use thicker layers of fine mica, to fold bilikiiigen in the ü lassei Jträger lying in the coil to be insulated. Be using stretchable art .ldcntrij.T these wrinkles do not arise. However, it cannot be avoided that when isolating nules with a rectangular cross-section, which is mostly : ..- In the case, put bands in the area of the bobbin edges .be stretched and the fine mica layers here. ilkn. That this is very detrimental to the quality of the insulation. : iüg is, is obvious. Very unfavorable at Lißerdein is the relatively short shelf life of the well-known "wet" mica tapes. In the icisten FäJien is even a storage of such tapes in the Dialing cabinet required. While lying down, the condition of the binding agent is constantly changing, Lierdiiivb can be very difficult when processing and, above all, irregularities, '.

The subject of the present invention is a process for the production of a conductor insulation, in particular of high-voltage windings, with a: is a carrier material and fine mica and impregnated with an insulating tape which is liquid at room temperature and is characterized by an insulating tape. that an embossed tape made of two layers of fine mica and a top layer of fiberglass fabric and one ^! inable material, such as a polyester-fiberglass blended fabric. Polyester fabric, polyester or diagonally arranged glass silk fabric is wound onto the conductor or a spool in such a way that the stretchable jugular layer in the tape is on the outside after the part to be insulated has been wrapped around.

The present invention eliminates the above-mentioned deficiencies in the "wet" mica-handlers. The tapes according to the invention consist of a total of four layers. In the middle there are / vv; i layers of fine liminer and on the outside each one layer of carrier fabric. In one case it is a glass silk fabric and in the other a polyester-glass silk mixed fabric in which the polyester threads (Trevira, Diolen, Dacron) are arranged in the KeU direction and the glass silk threads in the weft direction. Instead of this mixed fabric, you can also use diagonally cut fiberglass, rayon or rayon fleece. In order to save labor costs when applying the tapes later, it is advisable to use layers of mica as thick as possible. One layer of 250 g and one layer of 120 g / m ^{2 has} proven to be useful; two layers of 250 g / m each ² are also justifiable about 10 g / m ^2. The two double layers of! "rager and fine mica layer are now wound up together in such a way that the fine mica layer is on top of one another and the carrier materials are on the outside; then they are cut into ribbons.

After cutting and winding into tape rolls, the following arrangement results in the insulating tape: Stretchable outer carrier shoe, mica layer inside and an outer carrier layer made of glass silk fabric.

Auxiliary carriers and separating foils can be dispensed with in the tapes according to the present invention. The bands are sent and stored in this condition. They are only accepted shortly before processing whole rolls at room temperature under vacuum ma impregnated with a synthetic resin. As impregnation resins Resin-hardener mixtures which are liquid at room temperature are suitable, with at least the resin and / or The hardener component is liquid at room temperature and the mixture is liquid at room temperature Gives consistency. As a liquid resin component, bisphenol polyepoxides with a Epoxy equivalents of about 200 can be used. Cycloaliphatic can also be used for this purpose Polyepoxides and Triazin-Pofyepoxy.de if necessary are used in mixtures with one another to reduce the softening temperature of the resulting Insulation layer to be increased. For the aforementioned purpose z. B. Vinylycloxcrdiepoxycie or low-viscosity polyepoxides based on carboxylates in question. Also small additives of highly viscous or solid polyepoxides at room temperature, which are in the liquid polyepoxy compound loosen, own it, for the use as an impregnation resin.

As a liquid hardener component, in particular the dicarboxylic acid anhydrides, which are liquid at room temperature, such as methylhexahydrophthalic anhydride or methylendomethylene tetrahydrophthalic anhydride and low-melting anhydrides, such as hexahydrophthalic anhydride or mixtures thereof are used, in which also proportions of solid dicarboxylic acid anhydrides !! may be included. Suitable accelerators are compounds which have only an insignificant shelf life at room temperature affect, but cause rapid curing in the temperature range around 120 C, z. B. Phenol adducts of a tertiary aliphatic amine.

The following mixture can advantageously be used as the impregnating agent:

100 parts of a liquid polyepoxy compound based on bisphenol with an epoxy equivalent weight from 190,

85 parts of a liquid dicarbic acid anhydride:;,
0.15 part of an accelerator based on a tertiary aliphatic amine which is capped with a phenolic compound.

The vacuum impregnation of the raw fine mica

Rolling in this way has the great advantage that even thicker layers of fine mica can be impregnated perfectly, which is not the case with the known manufacturing processes described above.

The one for gluing backing material and F-a

The bisphenol polyepoxide used in PS mica dissolves after impregnating the tapes completely 111 dem Impregnating resin on. When llaizansaiz a corresponding additional amount of noise is taken into account.

fin The production of a winding insulation of Hochspamuiiigsspulen, z. B. von Roebclstäbcn, with the insulating tape according to the invention has been shown schematically in the figure:

The solvent-free liquid impregnation

medium ... see insulating tape on roll 5, the one has outer stretchable carrier 1 and contains Glimmerschichteii 2, 3 inside and with an outer carrier layer 4 is made of fiberglass fabric,

is wound onto the spool 6 so that the stretchable Carrier 1 is outside.

Through the use of fiberglass fabric as an outer support and fiberglass polycster fabrics (or other stretchable fabrics) for the other outer carrier causes that when wrapping the Coils and rods in the belts no old! Made of stretchable synthetic threads and fiberglass material is able to stretch accordingly. on the other hand the fine mica material cannot be overstretched because the other outer carrier made of glass fabric has a Prevents overstretching. In the structure according to the invention one is able to also tapes with a To apply a total thickness of 0.5 mm and above completely free of creases, which is very economical from an economic point of view brings many advantages.

When such tape rolls are impregnated under vacuum, such a material takes about BS ", ', Man on. This amount is completely sufficient for safe insulation. When later pressing the applied Isolation in connection with the hardening: some of the binding agent can still be pressed out will. It is advantageous to press in such a way that the finished insulation has a binder content of around 30%.

Insulations with "wet" fine mica tapes according to the invention are, from a dielectric point of view, the completely equivalent produced by vacuum impregnation.

One corresponding to the "wet" fine mica tape; Brcilmalerial can also be used for ironing Roebel bars and coils can be used. This has the advantage that you can iron the iron once at room temperature make and on the other hand can use relatively thick foils. Here, too, surrendered economically great advantages.

1 sheet of drawings

Claims (4)

Such insulation is applied in the form of patent claims: from wide materials or strips. The broad ma'.erialien are usually thin 1. A method for producing a conductor insulation film, consisting of a carrier (z. B. Glasscidenlation, in particular of high-voltage winding 5 tissue, rayon, rayon, paper), gen a mer composed and solvent-free synthetic resin medium which is liquid at room temperature and can be melted and hardened. These foils are wrapped in an ironing-impregnated insulating tape, characterized in that they are in a warm state on the conductors or conductors in that an impregnated tape is applied in bundles or coils. Then two layers of fine mica and one cover each are cured in a heated press. When using a layer of glass silk fabric and a stretchable synthetic resin-bonded mica tape, a dry, non-polyester fabric, polyester fleece or diagonally impregnated tape was first applied to material such as polyester-glass silk mixed fabric, and then the same arranged glass fiber fabric was applied to conductor 15 is later wound with the synthetic resin binder under vacuum or on a spool in such a way that the pressure is impregnated. Then there was an elastic carrier layer in the tape after the insulation had hardened again in appropriate ovens. wrap the part to be insulated is on the outside. I _n recent sit down so-called "wet" Fcin- 2. Process for the production of a conductor glimmable tape more and more through. It is about lation according to claim 1, characterized in that 20 here around tapes that were already in place before application that one has been impregnated by vacuum impregnation shortly before the binder. When processing Fine liming with binding agent is the binding agent to a greater or lesser extent More tape containing thick layers is liquefied. When using such tapes you need is turned. no expensive waterproofing equipment like them 3. insulating tape for producing the insulation according to 25 when using dry tapes, especially in claim 1, characterized in that as insulating large ⁷ Roebel bars of turbo generators, adhesives for connecting fine mica foil are required. With proper use and the supply and support materials used in the production of these tapes, the same Isola tape can be achieved with small amounts of a synthetic resin without a good quality as with vacuum impregnation. Very hardeners are used, which are advantageous in the later 30 with wet tapes, it is also that impregnation of the tape in the impregnation _m can apply to insulation of any thickness, which is a medium solution and together with this is not possible with a vacuum impregnation.
hardened. In the known manufacturing processes for such 4. A process for the production of an insulation "wet" fine mica tapes impregnated beinach claim 1, characterized in that a _35-play on an auxiliary carrier (paper treated on both sides tape with a binder containing a polyethylene-) a layer of fine mica liquid at room temperature Polyepoxydverbin- _lm d a layer of glass silk or rayon fabric-making bisphenol-based, a liquid dicarboxylic _c i _"e m mixture of curable synthetic resin and Lösungssäureanhydridhärter medium and an accelerator, the solvent is evaporated in the furnace and is used based on a tertiary amine. 40 wraps the material together with the sub-carrier on. After you cut ribbons from this later the subcarrier is removed before the tapes are applied to the spools. Another possibility- What used to be very successful for high-voltage 45 manufacturing was the lamination of carrier insulation electrical machines used mica with fine mica using less mersplittingmaterialicn (wide foils and tapes) with quantities of glue, impregnation in the above manner and Shellac and asphalt masses as binders are winding up the materials without an auxiliary carrier. That can in recent times it has been used more and more with synthetic resin but only if the binding agent is sufficient Bundcne mica materials replaced. The reason 50 is liquid. The binder is dried or hardened for this the continuously increasing requirements are required, it is necessary to have a struggles. Especially in the case of large turbo generators, separating foils are e.g. B. made of polyethylene, to run in, the thermomechanical stresses of the iso- lation has become so large that the older insulation is mica bands that when using mitmil thermoplastic binders meet the requirements 55 incoming auxiliary carriers or separating foils through the can no longer be fair. Remove them before applying the tapes While in the past only glow splitting was an additional workload. If it was taken, thin resin and fine mica to measure are still being used to an ever greater extent. This is to be understood as chemical or winding without separating foils, difficulties arise in the case of mechanically digested mica. 60 unrolling. The wet fine mica layer is severely damaged. The trade names for such materials are severely damaged. Sometimes it is on one of the z. B. SAMICA, COGEMICA, INTEGRATED and sometimes on the other side of the glass silk carrier. or RECONSTITUTED-MICA. Partly This can be avoided by combining two mica splits with fine mica. Wide webs or ribbons (a glass-silk carrier - while previously practically only 65 layers and a fine mica layer were used as carrier material after the im-paper, today more and more people are used to impregnate glass silk lying against each other together. Polyester fabrics and polyester vlics wraps. This will make the sensitive fine over. layers of mica through the two outer layers