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H.V.
Generator
AcceleratorChannel
Deflecting Magnet
Cable
www.siechem.comPolymer Cross-Linking Information
Siechem PV Power, Control & Data Transmission Cables Insulation & Sheath is energy electron beam irradiation cross linked from in house state of the art
irradiation centre with prestigious AERB, (Govt. of India) Mumbai approval. The Insulation and Sheath materials are made of polyolefin co-polymer. Polyolefin
consists of many random molecular chains, with no particular orientation, and no chemical bonds existing between chains before cross linking. After irradiation
cross linking ( as shown in figure-1) the free & random molecular chains are cross linked as shown in the figure-2
Electron Beam Cross Linked PV cables have higher Electrical, Mechanical, Thermal & Weathering properties. EBXL Siechem PV cables have
following special features.
1. Do not melt or flow even at very high temperatures.
2. High resistance against UV, Ozone & Hydrolysis.
3. Good flexibility, easy to strip
4. Improved abrasion/cut through
5. Better crush resistance
6. Solder iron resistance
7. Better over load characteristics
8. Resistance to stress cracking
9. Improved fluid, chemical & oil resistance
10. Slightly better flame resistance
11. Negligible change in thermal stability & electrical property
12. Improved fire resistance performance
13. Higher short circuit capacity
14. Improved high temperature mechanicals
15. High Degree of Cross-Linking and homogenity
16. No Polymer degradation due to high temperature as EB Cross-Linking occurs at room temperature
17. No oxidative degradation in polymers as observed in chemical cross-linking and so on.
Figure 2 Two random polymeric molecules
during and after irradiation cross linking
Figure 1 The State of Polymer Chain
before and after cross linking
A brief description of Cross-Linking, Product realiability, advantages and testing of Siechem PV cables and accessories.
A. DURING IRRADIATION
ELECTRON RADIATION
ELECTRON RADIATION
B.AFTER IRRADIATION
CROSSLINK
BONDS
Wires & Cables
Figure Layout of Electron beam
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During the irradiation process, high energy electrons are bombard over the insulation system. Figure 2 illustrates two random polymeric molecules being subject to
irradiation. The energy of irradiation ejects a hydrogen atom which then removes a neighboring hydrogen atom, forming molecular hydrogen gas (H ). The vacant sites
2
on the adjacent polymer chain then combine to create a cross-link bond.