The Complex for electron beam treatment of polymer products
Technical characteristics of the Complex for electron beam treatment of polymer products:
The complex is intended for cross-linking of polymers.
Dimensions of the Complex are 12m х 4m х 6m.
Weight of the Complex is 200 tons.
Capacity of the complex is 250 kW.
Electron beam treatment of polymer products such as:
1
Water pipes and couplings.
2
Heat shrink tubes and couplings.
3
Cables and wires.
4
Films.
Productivity of the complex: the volume of the processed products depends on the material and the
required radiation dose.
Technical illustration of the Complex for electron beam treatment of polymer products.
Example of placing the Сomplex in a factory.
Сross-linking of polyethylene pipes and couplings
The complex is designed for radiation cross-linking of polyethylene pipes and couplings. The complex
has unique equipment that allows to cross-link polymers simultaneously along the whole circumference
of the pipe. The homogeneity of the received dose and, consequently, the homogeneity of the cross-
linked material are guaranteed by the technology employed.

Productivity of the complex depends on the treated product.
The diameter of the tube can be up to 250 mm and the thickness of the wall can reach up to 25 mm.

Despite the fact that all polymer pipes have common technical and operational characteristics, certain
types of pipes (PE, PP, PVC, PEX and metal-plastic) also have their own distinctive features. Metal-plastic
pipe is a five-layer construction of three main and two bonding layers. The inner layer of the pipe is
made of cross-linked polyethylene. On the surface, a layer of special glue is applied, connecting
polyethylene with aluminum. The aluminum layer is made of a special foil with a thickness of 0.4 mm,
with a butt weld across the entire length. Welding of aluminum buttocks allows obtaining a pipe with an
ideally circular cross section. On the surface of aluminum, another layer of special glue is applied, which
binds aluminum to the outer layer of plastic PE-Xs. The entire pipe is linked via bombarding electrons on
both internal and external layers. In total, there are three methods for cross-linking of polyethylene: a
chemical method with peroxide (PE-Xa), a chemical method by silicone (PE-Xb), and a physical method
by electron irradiation (PE-Xs). In order to achieve the same quality, the percentage of peroxide
crosslinking should be 70%, silane - 65%, electronically- 60%.

Crosslinking of polyethylene is the process of formation of transverse and longitudinal bonds between
long polymer molecules under the influence of intense electron bombardment. In the case of physical
cross-linking, the polyethylene pipe is irradiated with hard X-rays. This process is very productive; its
speed is 80 m / min. Polyethylene obtained as a result of physical cross-linking is marked as PEX-C.
Under the influence of accelerated electrons and secondary gamma radiation, chemical bonds break
down, facilitates formation of free radicals which, in turn, recombine creating cross-links between
macromolecules.

According to this method, the production of pipes is divided into two separate stages: the production of
pipes on conventional pipe lines and the subsequent processing by high energies from electron
accelerators. In order to obtain even cross-linking of the pipe along both the thickness and perimeter,
the accelerator must have special sweeps of electron beams. For pipes with a wall thickness of 10 mm,
accelerators with an energy of 3 MeV are required, for 5 mm accelerators with an energy of 5 MeV with
capacity about 50-100 kW.
Improvements in properties resulting from irradiation:
1
Chemical properties
Metal-plastic pipes are resistant to the effects of various chemical solutions.
2
"Form memory"
After bending, the metal-plastic pipes retain the desired shape, which facilitates and accelerates the assembly of fittings and further work with the pipe.
3
Durability
The inner layer of metal-plastic pipes is made of high-strength cross-linked polyethylene. This ensures virtually no deterioration even at high flow rates. High resistance allows carrying out water supply pipelines with high internal pressure. Also, metal-plastic pipes are resistant to multiple, sharp pressure and temperature drops.
4
Expansion ratio
Due to the aluminum layer, the coefficient of linear expansion of the metal-plastic pipes is 0.025 mm / (mChK).
5
Heat resistance
It allows employing pipes for the installation in hot water systems.
6
Electrical safety
The special design of the fittings allows terminate electrical contact and put a barrier for premature destruction of the system due to the impact of electric fields.
7
Ecological compatibility
Metal-plastic pipes have no contra-indications for use in any type of drinking water pipelines. Due to the fact that the outer layer of the pipe is also cross-linked polyethylene or polypropylene, there is no need to protect the pipe the outside against the corrosion, and there is no need to paint it.
Сross-linking of heat shrink tubes and couplings
The complex is designed for radiation cross-linking of heat shrink tubes and couplings. The complex has unique equipment that allows to cross-link polymers simultaneously along the whole circumference of the pipe. The homogeneity of the received dose and, consequently, the homogeneity of the cross-linked material are guaranteed by the technology employed.

Productivity of the complex depends on the treated product.
The diameter of the tube can be up to 250 mm and the thickness of the wall can reach up to 25 mm.

The main task of heat shrink tubing is the isolation of contacts, but in addition, there are other ways of using such devices:
1
Shrinkage on a wooden or metal strut of a power transmission line support to protect against corrosion and rotting of wood in the ground.
2
Isolation from the corrosive environment of metal and water pipes.
3
Improvement of the ergonomics of the tool handles and sports equipment, by using ribbed or ribbed tubes.
4
Longitudinal sealing of bundles of cable. In addition to external insulation, due to a special tape, the space between the cores is completely filled and isolated.
5
Cable protection from high temperatures. There are products for which a working temperature ranges from -65 to +260 degrees. This additionally helps the cable to withstand extreme operating conditions in the vicinity of open sources of fire or heat. Such brands are called teflon or fluoroplastic.
6
Transformation of conventional tools into a kind of dielectric, for example by isolating the tip of a screwdriver.
The use of heat shrinkage is based on the shape memory effect. It is achieved by radiation exposure. For instance, if the polymer is placed in a powerful flow of electrons, at the molecular level, there is a connection of neighboring macromolecules with each other. This technology is called cross-linking technology. After this operation the polymer itself becomes more elastic, and the product, when heated, acquires its original shape and initial dimensions.

Theoretically, the same tube can be seated an infinite number of times. If you had a device for warming up and blowing it, it would turn into a reusable product. And the term of its storage in the original form is dozens of years. All characteristics and quality of the product, subject to certain requirements, do not depend substantially on the date of manufacture.

Nowadays, the heat shrink tubes have gained immense commercial and technical importance throughout the world. However, the main field of application remains to be the sphere of electronics and electrical engineering.
Non-flammable
Material is of great importance. Due to the the composition of this material, it has such properties are pre-set. For example, if add flame retardants, the tube acquires the properties of self-extinguishing and is denoted by the NG index.

This does not mean that it does not burn at all. But in the absence of an external source of flame, it quickly extinguishes. This is ensured by preventing the entry of oxygen to the site of fire by flame retardants.
Сross-linking of cables and wires couplings
The complex is designed for radiation cross-linking of heat shrink tubes and couplings. The complex has unique equipment that allows to cross-link polymers simultaneously along the whole circumference of the pipe. The homogeneity of the received dose and, consequently, the homogeneity of the cross-linked material are guaranteed by the technology employed.

Productivity of the complex depends on the treated product.
The diameter of the tube can be up to 80 mm and the thickness of the wall can reach up to 25 mm.

Radiation crosslinking allows more flexibility in the choice of raw materials and in the design and construction of cables. Not only individually insulated cable cores but also several cores twisted together, or complete leads and cables, can be crosslinked in a single process step. If the application requires the use of an inner core insulation which is sensitive to radiation, it is even possible to crosslink the outer sheath only. If desired, company gives support in optimizing the radiation dose and the polymer compound used, in order to indentify the best option in terms of technical properties and costs. These possibilities make radiation crosslinking a competitive alternative to other crosslinking processes.

Another important application for radiation crosslinked cables are connecting cables for photovoltaic systems. Only radiation crosslinked cables are in a position to fulfill the legal requirements for working temperatures and arc resistance, and to withstand stress from industrial influences such as acid rain, exhaust gases, ozone and other chemical substances. Unlike chemical crosslinking, in radiation crosslinking only one process step is needed to crosslink the double insulating sheath generally required for photovoltaic cables.

In addition to good dielectric properties, XLPE insulation has a wider range of operating temperatures and higher mechanical characteristics than other materials. The transition to cables with SPE insulation instead of cables with BPI (paper-impregnated insulation) is due to a number of undeniable advantages:
1
Higher durability.
2
Low cost on reconstruction and maintenance of cable lines.
3
Improvement of the ergonomics of the tool handles and sports equipment, by using ribbed or ribbed tubes.
4
Low dielectric losses (dielectric loss factor 0.001 instead of 0.008).
5
Greater throughput due to an increase in the permissible heating temperature of the conductors.
6
Increased resistance to heat pressure.
7
Low moisture absorption.
8
More ecological installation and operation (absence of lead, oil, bitumen).
9
Absence of level restrictions during laying.
10
Better resistance to oil and chemicals.
11
Better resistance to hydrolysis.
12
Higher flexural strength (alternate bending strength).
13
Better abrasion properties.
14
Improved resistance to stress cracking.