Technical Information Power And Control Cables Power Appendixes XLPE (Cross-liked Polyethylene) Comparison Table of Cross Linking Methods صفحه Comparison Table of Cross Linking Methods
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Peroxide |
Silaine |
Irradiation |
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Curing Media |
Organic Peroxide |
Silane Compound |
High Frequency Radiation |
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Curing Equipment |
High Pressure & High Temperature Curing Duct |
Saturated Steam Bath |
Electron Beam Generator |
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Strong Point |
Most Common No Thickness Limit |
Cheap Equipment Low Energy Cost High Speed Line |
High Speed Extrusion Low Running Cost |
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Weak Point |
Expensive Equipment Limited Line speed High Energy Cost |
Wall Thickness Limit |
Expensive Equipment Limited Beam Cap. Wall Thickness Limit |
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Application Voltage |
6000 v – 500 Kv |
150 V – 33 kv |
Max 600v |
WATER TREEING CAUSES
Water treeing is the major defect of insulation of medium and high voltage cables.
It is independent of the Peroxide , Silaine or Irradiation methods of cross-linking and It can be categorized as following matters :
1- Impurities
related to the purity of the raw materials for the insulation and very important the semiconducting screens
2- Moisture in cable screens and insulation
2a. after production (is low both cables i.e. Silaine cured or dry cured ; was high in steam cured cables)
2b. during service operation (can be kept low in both cables i.e. Silaine cured or dry cured by water tight constructions)
3- Electrical Fields
Only Depends on fabrication of conductor (to be round) and tightness of layers and totally no sharp edges!
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There are two most common
* Vented tree |
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