U70BL/255/146/320 IEC Standard profile 70kn suspension Tempered glass Insulator CTV254

• Model:U70BL
• U   Refers To Disc Suspension Insulator
• 70 indicates a rated Mechanical failing load  of 70kN
• B   For Ball And Socket Type
• L   Stands For Long Steel Foot

• 146- indicates that the height of the insulator structure is 146mm, and there are also insulators with spacing of 127mm.
• 255- indicates that the diameter of the insulator disc is 255mm, and there are also insulators with disc diameters of 280mm, 300mm,  320mm, 380mm, 420mm, etc.
• 320- indicates that the creepage distance of the insulator is 320mm, and there are also insulators with creepage distances of 400mm, 450mm, 550mm, etc.

• Type: Standard profile Toughened Suspension Type
•  Rated mechanical load: 70kn (about 7 tons)
• Purpose: Widely applicable as insulation support for medium and high voltage transmission lines and substation equipment, capable of stable operation under various climatic conditions.

• The product model is in accordance with  IEC60383-1:1993，MOD / GB/T1001.1
• The connection structure is in accordance with GB/T4056-2008(IEC60120:1984,MOD) and BS 3288 part lll.
• According to customer requirements, the locking pin can be either W-pin or R-pin.
• lf there is no special instruction, W pin is used for U70BL

Suspension insulators consist of the following elements:

• - One dielectric made of toughened glass with the appropriate properties and shape for the environmental conditions in which it must function.
• - One hot-dip galvanized nodular or ductile malleable cast iron cap.
• - One hot-dip galvanized forged steel pin.
• - The cap and pin are assembled on the glass piece using aluminous cement with the appropriate properties to withstand the thermomechanical efforts.

Lastly, the insulator cap has a stainless steel or phosphor bronze locking device (split pin) which secures the coupling of the units.

Similarly, the pins may be protected using an anti-corrosion zinc sleeve (sacrificial anode), when requested. This zinc sleeve is strongly recommended for insulators which are going to be used in lines with heavy pollution.

Under long-term electrical stress, contaminants can trigger local arcs, leading to insulator surface carbonization (electrocorrosion). Enough creep distance to disperse the strength of the electric field, reduce the risk of local discharge and extend the life.