Bow-tie treeing effect in cross-linked polyethylene insulated cables

Extensive studies have been made in recent years on water treeing phenomena in polyethylene (PE) and cross-linked polyethylene (XLP) insulated cables. There are reports on many types of water trees found in cables removed from the field.
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These are classified into two types, a) vented, considered to be open to the atmosphere, and b) nonvented, considered to be closed to the atmosphere.
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