RU2528840C1 - Method to manufacture fibre glass items with low value of surface electric resistance - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: in method realisation they clean a die of a future item, degrease it with subsequent application of separating wax and then a protective-finishing layer is applied - gel coat, with addition of current-conducting hydrocarbon fibres. Drying is carried out with subsequent hand moulding. Cut material is laid into the die, forming the item, then resin mixed with catalyst is applied, afterwards using brushes and/or soft rollers they evenly distribute the mixture along the die. The produced laminate is rolled with a stiff roller with its subsequent withdrawal from the mould and exposed to mechanical treatment.

EFFECT: production of items with low value of surface electric resistance and higher strength.

Description

The invention relates to methods for manufacturing fiberglass products.

The prior art document RU 2430830 C1, cl. B28B 11/00, publ. 10/10/2011, which describes a method for manufacturing products using polyester resins reinforced with glass mat, applied to the surface of a prefabricated matrix form and precisely repeating its shape.

However, in the known method is not disclosed a method of manufacturing a fiberglass product with a low value of surface electrical resistance.

The technical result of the described invention is the ability to obtain fiberglass products with low surface electrical resistance and high strength.

The technical result is achieved by a method of manufacturing fiberglass products, in which the matrix of the future product is cleaned, degreased using cotton material moistened with an alcohol solution, followed by applying a separation wax and a protective and decorative layer is applied - gelcoat with the addition of thin conductive hydrocarbon fibers. Next, drying is carried out, followed by manual molding, the cut material is laid into the matrix, forming the product, then a resin mixed with a solidification catalyst is applied, after which the mixture is evenly distributed over the matrix with brushes and / or soft rollers, after which the resulting laminate is rolled up with a hard roller, followed by extraction it is out of shape and subjected to machining.

The thickness of the used fiber is from 10 to 100 microns, the length is 0.8-5 cm. The fibers added to the gelcoat are randomly arranged in it. As such fibers can be used carbon structural thread UKN-5000 (GOST 28008-88) or UKN-M-6K.

The technical result indicated in this invention is achieved in the case of using any resins, materials for reinforcing and solidification catalysts, since The effect of reducing electrical resistance is achieved by adding carbon fiber to the gelcoat. As a result of using this invention, only on the surface of the fiberglass product, the electrical resistance decreases, and it acquires electrical conductivity.

A method of manufacturing fiberglass products in this case is the method of manual molding.

The procedure for manufacturing fiberglass products by manual molding takes place in several stages. The first stage is preparatory: the matrix surface of the future product is cleaned, degreased and a separating wax is applied. After that, a protective and decorative layer - gelcoat is applied to the matrix. The gelcoat forms the outer surface of the future product, setting the color and providing protection from external factors (ultraviolet, water, chemicals, etc.). When thin conductive carbon fibers of black color are added to the gelcoat, the product gets a characteristic color. Since the thickness of the gelcoat does not exceed one millimeter, carbon fibers are visible on the surface of the product. Carbon fibers mixed in gelcoat randomly interweave inside and make the product surface look like paper streaked with short strokes.

After the gelcoat has dried, they proceed to the next stage - molding. A pre-cut glass material or another type of reinforcing filler is laid in the matrix, forming the "skeleton" of the future product. Then, resin, previously prepared and mixed with the catalyst, is applied to the prepared glass material. The resin is evenly distributed throughout the matrix using brushes and soft rollers.

The final stage is rolling. To remove air bubbles from the uncured laminate that may affect the quality of the finished product, the laminate is rolled with a rigid roller. After curing, the finished product is removed from the mold and subjected to machining: trimming excess fiberglass at the edges, drilling holes, etc.

Also provided is a method of manufacturing fiberglass products, which is sprayed. This process is carried out in stages:

- application of gelcoat;

- application of resin and chop (chop - chopped roving);

- fiberglass seal in the matrix.

Application of gelcoat and fiberglass is carried out using special equipment. In this method, the following features must be observed:

- Spray should be applied using continuous and parallel strips overlapping by 20% at a constant speed.

- Spray in two or three passes to obtain the desired film thickness.

- Always spray the next layer perpendicular to the previous one.

- Stop the spray gun outside the mold.

- For hard-to-reach places in the form in which it is impossible to maintain the correct position of the spray gun, a brush can be used to apply the layer.

- It is also necessary to check the thickness of the wet film, which should be 0.5-1.0 mm, depending on the purpose of the reinforced plastic product.

Gelcoat must be applied in a spray booth or on a separate area of the workshop

- with effective ventilation;

- with good lighting;

- in the absence of dust;

- at a temperature of 18-25 degrees;

- at an air humidity of 80% (max.).

For spraying gelcoat and resin, spray guns of the RS series are used; these guns have a platform for internal and external mixing, as well as for installing a chopper. The chopper is mounted directly on the gun itself and is designed to cut the fiber added to the mixture. The chopper uses the torque of an air motor to cut the fiber added to the mixture. An air stream is created in the chopper that allows it to work at low temperatures and provides the best performance when working with fiber.

Equipment for the production of fiberglass spraying automatically carries out a rigid dosage of polyester resin and catalyst, chopping the roving (a bundle of continuous fiberglass filaments) into parts of a given size (chops, length 0.8-5 cm). After chopping, parts of the fiberglass fall into the stream of polyester resin from the spray gun and are impregnated with it during transfer to the matrix. The share of manual labor remains the compaction of fiberglass in the matrix with a rolling roller.

In the described manufacturing process of fiberglass products by spraying, conductive carbon fibers are also added with a thickness of 15 to 100 microns in gelcoat. As a result, the surface of the product, as in the previous case, has a characteristic color, similar to paper streaked with strokes. This effect occurs because black carbon fibers randomly added to the gelcoat are visible on the surface.

Low surface resistance avoids the accumulation of static electric charge on the surface of the product and the occurrence of a spark that can ignite explosive gases and mixtures that may be present in the surrounding atmosphere. Fiberglass products with low surface electrical resistance can be used in industry or in the home if there is a mixture of explosive gases in the surrounding atmosphere. This quality of the products obtained allows them to pass explosion protection certification. The presented process can be applied to various methods of manufacturing fiberglass products, which are known from the previous level of technology development.

Claims (1)

A method of manufacturing fiberglass products, characterized in that they clean the matrix of the future product, degrease it with a cotton material moistened with an alcohol solution, followed by applying a separation wax and apply a protective and decorative layer - gelcoat with the addition of conductive hydrocarbon fibers, carry out drying followed by manual by molding, cut material is laid in the matrix, forming the product, then a resin mixed with a catalyst is applied, followed by brushes and / or soft mixture evenly distribute the mixture over the matrix, after which the resulting laminate is rolled with a hard roller, followed by removing it from the mold and subjected to machining.