
U40B Toughened Glass Disc Insulator 40kN








Glass Suspension Insulators
Product Overview
The smallest disc in the U-series toughened glass suspension range, designated U40B/110 to IEC. Diameter is 178 mm, height 110 mm and creepage 185 mm, with an 11 mm socket coupling. Mechanical failing load is 40 kN with a 20 kN routine test, and the electrical figures are 25 kV wet power frequency withstand, 50 kV dry lightning impulse and 90 kV power frequency puncture.
Key benefits
Why Buyers Choose This Part
- 40 kN failing load with a 20 kN mechanical routine test on every disc
- 178 mm diameter keeps string weight and wind load down on light lines
- 11 mm socket coupling matches light-duty string hardware
- Toughened glass shows a puncture by shattering, visible from the ground
Application scenarios
Where It Is Used
- Light distribution and sub-transmission suspension strings
- Short spans where a 70 kN disc is more than the design needs
- Dead-end and tension assemblies on small conductors
- Replacement of aged U40B discs on existing strings
Who it is for
Who It Suits
- Overhead line contractors building light suspension strings
- Utilities maintaining older U-series strings
- Distributors stocking IEC glass disc insulators
Problems it solves
What Goes Wrong Without The Right Part
- Oversized discs that add unnecessary weight and cost to a light line
- Punctured units that cannot be found on a visual patrol
- Coupling mismatch when the string hardware is 11 mm
- Strings assembled from mixed disc ratings that no one has documented
Technical features
How It Is Built
- IEC designation U40B/110
- 178 mm diameter and 110 mm height
- 185 mm creepage distance
- 11 mm socket coupling
- 40 kN mechanical failing load, 20 kN mechanical routine test
- 25 kV wet power frequency withstand voltage
- 50 kV dry lightning impulse withstand voltage
- 90 kV power frequency puncture voltage
- 50 µV radio influence voltage, 18/22 kV corona visual test
Specifications
Published Figures For This Product
Every value below comes from the manufacturer data for this item. Figures not listed are confirmed against the drawing before an order is placed.
| Creepage Distance | 185 mm |
|---|---|
| Socket Coupling | 11 mm |
| Wet Power Frequency Withstand Voltage | 25 kV |
| Dry Lightning Impulse Withstand Voltage | 50 kV |
| Power Frequency Puncture Voltage | 90 kV |
| 50 Μv Radio Influence Voltage, Corona Visual Test | 18/22 kV |
Materials
Materials
- Toughened glass dielectric
- Galvanised cap and pin
- Portland cement bonding
Manufacturing
Process
- Glass pressing
- Thermal toughening
- Cementing
- Galvanising
- Mechanical routine test
Quality control
Testing
- 20 kN mechanical routine test on every disc
- Power frequency puncture test to 90 kV
- Corona visual test at 18/22 kV
Certifications
Certification
- IEC designated U40B/110
- ISO 9001 quality management system
Customisation
Customisation Options
- Other U-series ratings from 40 kN up to 160 kN
- Coupling sizes from 11 mm to 20 mm
- Cap marking on request
Comparison
How It Compares
| U70B disc | U70B is 255 mm in diameter with 320 mm creepage and a 70 kN failing load. Step up to it when the span or conductor size needs more mechanical margin. |
|---|---|
| Porcelain disc of the same rating | A punctured glass disc shatters and is spotted on patrol, while a punctured porcelain disc normally looks intact. |
Use guide
Before You Order And After It Arrives
- Check the string hardware takes an 11 mm socket coupling
- Do not mix disc ratings within one string
- Fit split pins fully on every coupling during assembly
- Log the rating used per span so future replacement matches
Questions
U40B Toughened Glass Disc Insulator 40kN Questions
What is the IEC designation?
U40B/110.
What is the mechanical failing load?
40 kN, with a 20 kN mechanical routine test applied to every disc.
What is the creepage distance?
185 mm.
What coupling size does it use?
An 11 mm socket coupling.
What other ratings are available?
The U-series runs from U40B through U70B, U100B, U120B and U160B, with creepage from 185 mm to 400 mm.
What is the puncture voltage?
90 kV power frequency, with a 50 kV dry lightning impulse withstand.
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Quote For U40B Toughened Glass Disc Insulator 40kN
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