Glass Double Umbrella Type Insulator
Double-shed and triple-shed glass discs from 70 kN to 300 kN, for heavy pollution and high creepage in a narrow string.
- Failing load
- 70–300 kN
- Creepage
- 450–550 mm
- Disc diameter
- 280–330 mm
- Sheds
- Double and triple
Two or three sheds on one disc give the creepage of a much larger single-shed unit, without widening the string or lengthening the hardware. It is the profile used where pollution is heavy and the string has to stay short.
The table lists the double-shed (D) types. Triple-shed (T) types use the same ratings and a different shed count; U160BT is included as the example.
Ratings run from 70 kN to 300 kN. Above 160 kN the coupling goes from 20 mm to 24 mm, so the string hardware changes with the disc.
Specifications
Values published for each type. Double-shed discs, 280 mm to 330 mm diameter.
| Type | Mechanical failing loadkN | Disc diametermm | Spacingmm | Creepagemm | Couplingmm | Dry power-frequency withstandkV | Wet power-frequency withstandkV | Lightning impulse withstandkV | Power-frequency puncturekV |
|---|---|---|---|---|---|---|---|---|---|
| U70BLD | 70 | 280 | 146 | 450 | 16 | 80 | 45 | 120 | 130 |
| U100BLD | 100 | 280 | 146 | 450 | 16 | 80 | 45 | 120 | 130 |
| U120BLD | 120 | 280 | 146 | 450 | 16 | 80 | 45 | 120 | 130 |
| U160BD | 160 | 280 | 155 | 450 | 20 | 80 | 45 | 120 | 130 |
| U170BD | 160 | 280 | 170 | 450 | 20 | 80 | 45 | 120 | 130 |
| U210BD | 210 | 280 | 170 | 450 | 20 | 80 | 45 | 120 | 130 |
| U240BD | 240 | 280 | 170 | 450 | 24 | 80 | 45 | 120 | 130 |
| U300BD | 300 | 330 | 195 | 485 | 24 | 85 | 50 | 130 | 130 |
| U160BT | 160 | 320 | 170 | 550 | 20 | 85 | 50 | 130 | 130 |
Radio interference ≤50 μV at 10 kV and 1 MHz; visible corona 18/22 kV pin and cap; power-frequency arc test 0.12 s at 20 kA; impulse overvoltage puncture withstand 2.8 p.u. The catalogue gives no unit weight for the D types.
Choosing a Type
Double or Triple
The T version adds a third shed on the same body. It is chosen where the pollution class is one step above what the D version covers.
Coupling Change
16 mm and 20 mm couplings cover the 70–240 kN discs; 24 mm starts at U240BD and continues to U300BD.
Every disc is routine-tested before it is packed, and each type is type-tested before it is offered for supply.
Ask about Glass Double Umbrella Type Insulator
Send the type designation, the quantity and the standard the project is working to. We reply with a price and a delivery date.
We usually reply within one working day.