Insulation Enhancement Products — Overhead Line & Bus Covers
Insulcover overhead line covers, GSOC silicone line covers and GPFIC bus connection covers — a retrofit insulation system that prevents wildlife-caused flashovers on bare conductors and bus connections.
- ANSI C37.20.2
- ASTM D2671
- ASTM D2303
Installation instructions
Full dimensional specifications and technical data — download the sheet for your size.
Choose a size
Selection Charts
| Gala Code | Conductor Dia.(mm) | Packaging(Mtr./Roll) |
|---|---|---|
| GOC 1 | upto 10 | 30 |
| GOC 1A | upto 15 | 30 |
| GOC 2 | upto 22 | 30 |
| GOC 3 | upto 28 | 30 |
| GOC 4 | upto 38 | 30 |
Insulcover is available in five sizes that cover conductors up to 800 sq. mm. Source: GALA Overhead Line Cover (INSULCOVER) catalogue sheet, Issue 2, December 2025.
GSOC-M — 2.0 mm wall
| Gala Code | Conductor Dia.(mm) | Thickness(mm) | Packaging(Mtr./Roll) |
|---|---|---|---|
| GSOC-M-15 | upto 15 | 2.0 | 15 |
| GSOC-M-20 | upto 20 | 2.0 | 15 |
| GSOC-M-24 | upto 24 | 2.0 | 15 |
| GSOC-M-28 | upto 28 | 2.0 | 15 |
| GSOC-M-32 | upto 32 | 2.0 | 15 |
| GSOC-M-38 | upto 38 | 2.0 | 15 |
Source: GALA Silicone Overhead Line Cover catalogue sheet, Issue 2, March 2026.
GSOC-H — 2.7 mm wall
| Gala Code | Conductor Dia.(mm) | Thickness(mm) | Packaging(Mtr./Roll) |
|---|---|---|---|
| GSOC-H-15 | upto 15 | 2.7 | 15 |
| GSOC-H-20 | upto 20 | 2.7 | 15 |
| GSOC-H-24 | upto 24 | 2.7 | 15 |
| GSOC-H-28 | upto 28 | 2.7 | 15 |
| GSOC-H-32 | upto 32 | 2.7 | 15 |
| GSOC-H-38 | upto 38 | 2.7 | 15 |
Source: GALA Silicone Overhead Line Cover catalogue sheet, Issue 2, March 2026.
GSOC-H3 — 3.0 mm wall
| Gala Code | Conductor Dia.(mm) | Thickness(mm) | Packaging(Mtr./Roll) |
|---|---|---|---|
| GSOC-H3-15 | upto 15 | 3.0 | 15 |
| GSOC-H3-20 | upto 20 | 3.0 | 15 |
| GSOC-H3-24 | upto 24 | 3.0 | 15 |
| GSOC-H3-28 | upto 28 | 3.0 | 15 |
| GSOC-H3-32 | upto 32 | 3.0 | 15 |
| GSOC-H3-38 | upto 38 | 3.0 | 15 |
Source: GALA Silicone Overhead Line Cover catalogue sheet, Issue 2, March 2026.
GSOC-EH — 5.0 mm wall
| Gala Code | Conductor Dia.(mm) | Thickness(mm) | Packaging(Mtr./Roll) |
|---|---|---|---|
| GSOC-EH-15 | upto 15 | 5.0 | 15 |
| GSOC-EH-20 | upto 20 | 5.0 | 15 |
| GSOC-EH-24 | upto 24 | 5.0 | 15 |
| GSOC-EH-28 | upto 28 | 5.0 | 15 |
| GSOC-EH-32 | upto 32 | 5.0 | 15 |
| GSOC-EH-38 | upto 38 | 5.0 | 15 |
Self-fusing silicone tape: 63.5 mm (width) × 0.76 mm (thickness). The quantity of tape required depends on the conductor size. Source: GALA Silicone Overhead Line Cover catalogue sheet, Issue 2, March 2026.
Material properties
Technical Specification
| Properties | Value | Test method |
|---|---|---|
| Tensile Strength | 9 N/mm² (Mpa) (min.) | ASTM D638 |
| Ultimate Elongation | 250% (min.) | ASTM D638 |
| Density | 1.20 ± 0.2 gm/cm³ | ASTM D792 |
| Hardness | 40 ± 5 Shore D | ASTM D2240 |
| Water Absorption | 0.5% (max.) | ASTM D570 |
| Low Temperature Flexibility (-40 °C for 4 hrs.) | No Cracking | ASTM D2671 |
| Continuous Temperature Limit | -45 °C to +105 °C | IEC 216 |
| Dielectric Strength | 20 kV/mm (min.) | ASTM D149 |
| Volume Resistivity | 1 x 10¹³ Ohm.cm (min.) | ASTM D257 |
| Dielectric Constant | 5 (max.) | ASTM D150 |
Source: GALA Overhead Line Cover (INSULCOVER) catalogue sheet, Issue 2, December 2025.
Dimensions & Drawings
Birds, animals, vegetation and airborne debris bridge phase-to-phase or phase-to-earth clearances on bare busbars, conductors and connections, causing flashovers that damage equipment and can electrocute the animal. Gala's Insulation Enhancement range insulates the vulnerable bare metalwork to prevent it.
Insulcover is a wrap-around line cover in non-tracking cross-linked polyolefin for bare overhead conductors, used in applications up to 66 kV and installed with the Split Insulation Tube Tool at one stationary location, without conductor replacement. GSOC non-tracking silicone line covers field-install over bare conductors for insulation enhancement up to 765 kV.
Read the full overview
GPFIC bus/bushing connection covers are UV-stable and track-resistant, sized for circuit breaker bushings, bus standoff insulators, capacitors, transformer bushings, voltage regulators and potential transformers. They are field-trimmed at the entry and exit holes, and can be re-entered and reused for later maintenance.
GBBS sheets are non-shrinkable sheets that secure and insulate the underside of structures where clearances are reduced.
Covered on this page
- INSULATION ENHANCEMENT PRODUCTS
- Cable End Caps - Live End Caps
- Overhead Line Cover:
- Overhead Line Tube:
- Overhead Line Cover - Silicone:
- Silicon Interlocking Overhead Line Cover:
- Bus Connection Insulating Covers (Reusable):
- Other Products:
Features & Benefits
- Meets ANSI C37.20.2 standards
- High dielectric strength, UV and ozone resistant
- Resists chemical corrosion from acid, alkali and salt
- Many standard sizes in stock plus custom CAD design assistance
- GPFIC bus connection covers are field-trimmable and reusable
- Installed with a stationary Split Insulation Tube Tool
Applications
- Retrofit insulation of bare overhead conductors up to 66 kV (Insulcover) and up to 765 kV (GSOC silicone cover)
- Bird and animal flashover protection at substations
- Circuit breaker bushings, bus standoff insulators, capacitor and transformer bushings, voltage regulators and potential transformers (GPFIC covers)
- High-voltage insulator protection from bird excretion
Standards & Compliance
- ANSI C37.20.2
- ASTM D2671
- ASTM D2303
- ASTM D149
- IEC 216
FAQs
Frequently Asked Questions
What is the Insulation Enhancement Products used for?
It is used for:
- Bird and animal flashover protection at substations
- Circuit breaker bushings, bus standoff insulators, capacitor and transformer bushings, voltage regulators and potential transformers (GPFIC covers)
- High-voltage insulator protection from bird excretion
How do I choose the right size?
Use the selection chart on this page: it lists every code with its dimensions. If you are not sure which fits, send the dimensions you are working to with the form below.
Which standards and test methods are quoted for it?
These, with the values in the Technical Specification on this page:
- ANSI C37.20.2
- ASTM D2671
- ASTM D2303
- ASTM D149
- IEC 216
Where can I download the datasheet?
From the "Download datasheet" button at the top of this page, or here:
Can I get a quote, a sample or a size that is not listed?
Send your cable details, quantity and application with the "Request a Quote or Sample" form at the foot of this page. For a size or variant that is not in the chart, describe what you need there, or use Technical support at the top of the page, and the technical team will confirm what can be supplied.
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