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Focus on heat shrink tube, cold shrink tube, wire and cable identification labels, Volsun Electronics is your ideal choice for industry insulation, sealing and protection.

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Self-locking silicone overhead line cover is made of high quality silicone rubber material, with excellent electrical, anti-leakage marking performance, excellent weather resistance, high mechanical properties, with hydrophobic and hydrophobic migration characteristics, high and low temperature resistance is extremely excellent. It is convenient and simple to install, saves labor and time, and is used for insulation protection of cables and wires, and increases the safe distance between objects and cables/ wires.


Soft and resistant to bending
Long service life, aging resistance, corrosion resistance
Flame retardant performance: V-0, non-flame retardant can be customized
Color: Red, Gray (customizable)
Easy installation, no flame required, short power-off construction time



Technical Performance

Item Typical value Test method
Electrical Strength Test ≥20kV/mm GB/T 1408.1-2006
Volume Resistivity ≥1×1014Ω·cm GB/T 1410-2006
Dielectric Constant 2~3 GB/T 1409-2006
Shore Hardness 70±5A GB/T 531
Mechanical Properties before heat ageing
Tensile Strength ≥4.0MPa GB/T 528
Elongation at break ≥200% GB/T 528
After Heat ageing(180℃, 7d)
Tensile Strength Change ±30% GB/T 528
Elongation Change ±30% GB/T 528
Low Temperature Elongation(-15℃, 2h) ≥20% GB/T 2951.4-1997
Low Temperature Flexibility(-50℃, 4h) No crack UL224-2004
High Temperature Crack Resistance(155℃, 2h) No crack GB/T2951.6-1997

LJ type aluminum strand applicable product selection table

Nominal cross-sectional area(mm²) Nominal outside diameter(mm) Specifies the specifications of the insulation bushing(mm)
16 5.10 Ф 8
25 6.45 Ф 10
35 7.50 Ф 10
50 9.00 Ф 12
70 10.80 Ф 14
95 12.50 Ф 16
120 14.25 Ф 18
150 15.75 Ф 20
185 17.50 Ф 22
240 20.00 Ф 24
300 22.40 Ф 28
400 25.90 Ф 32
500 29.12 Ф 35
Note: Special size and packaging can be customized upon request.

Voltage level and wall thickness level corresponding table

Voltage Rate ≤10kV ≤35kV ≤110kV ≤220kV
Wall thickness 2.0±0.3mm 2.6±0.4mm 4.0±0.5mm 6.0±1.0mm


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