Anti Bird Disk
| Material | Polycarbonate |
| Disk thickness | 8 mm |
| Dielectric strength | Min 15 kV/mm |
| Izod impact | Min 640 J/m |
| Tensile yield | Min 55 MPa |
| Specific gravity | 1.19 – 1.22 |
| O-ring | HTV silicon rubber |
| Application | 25 kV railway & metro OHE |
Standards & references
- RDSO SMI TI/MI/0059 Rev.3
- Revision effective March 2025
- Polycarbonate to ASTM D3935-21
- Flammability UL-94 V-2 or higher
- Packing Saddle RI No. 1174
- Catenary Susp. Clamp RI No. 1161
Vaibhav Laxmi Industries manufactures Anti Bird Disks for railway, metro, and OHE applications. The disk is fitted near 25 kV insulators to prevent birds from perching and causing flashovers, short circuits, tripping, and insulator damage. It is manufactured as per RDSO SMI No. TI/MI/0059 Rev.3, the latest RDSO maintenance instruction for Anti-bird disc and packing saddle arrangements.
RDSO SMI Based Design
The Anti Bird Disk follows the requirements of RDSO Maintenance Instruction TI/MI/0059 Rev.3, issued by the Traction Installation Directorate, Research Designs & Standards Organisation, Ministry of Railways. The instruction covers Anti-bird disc arrangements for preventing bird faults on railway OHE insulators, especially in bird-prone and tripping-prone sections. Both the maintenance instruction and the approval by RDSO issued to M/S Vinayak Industries (a sister concern of VLI).
Product Purpose
Birds sitting on OHE insulators and fittings can create a path between live equipment and earth. This may lead to:
- OHE tripping
- Flashing of insulators
- Insulator breakage or parting
- Short circuits
- Railway traffic disruption
- Higher maintenance cost
The Anti Bird Disk creates a physical barrier around the insulator area. Its spiked outer profile discourages birds from sitting near live OHE parts.
Applications
Suitable for use on:
- Railway OHE sections
- Metro OHE systems
- Stay tube insulators
- Bracket tube insulators
- 9-ton insulators
- Composite insulators
- Porcelain insulators
- Bird-prone and tripping-prone locations
Material and Construction
The Anti Bird Disk is manufactured from polycarbonate material as specified in the RDSO SMI. The material is selected for outdoor railway use because it offers strength, insulation, impact resistance, and weather resistance.
Material requirements include:
- Polycarbonate as per ASTM D3935-21
- UL-94 V-2 or higher flammability rating
- UV and weather resistant
- Good electrical insulation
- Impact resistant construction
- Dimensional stability
- Silicon O-ring fitment
Technical Specifications
| Parameter | Specification |
|---|---|
| Product | Anti Bird Disk / Anti Bird Disc |
| Application | Railway and metro OHE |
| Voltage side | 25 kV OHE side |
| RDSO reference | TI/MI/0059 Rev.3 |
| Material | Polycarbonate |
| Disk thickness | 8 mm as per RDSO drawing |
| Dielectric strength | Minimum 15 kV/mm |
| Izod impact strength | Minimum 640 J/m |
| Specific gravity | 1.19 to 1.22 |
| Tensile yield strength | Minimum 55 MPa |
| O-ring material | HTV type silicon rubber |
| O-ring thickness | 4 ± 1 mm |
| Marking | Manufacturer name/logo and year of manufacturing |
Testing and Inspection
Anti Bird Disks are supplied with testing and inspection parameters aligned with the RDSO SMI. Tests include:
- Visual examination
- Dimensional verification
- Specific gravity test
- Tensile yield strength test
- Izod impact test
- Flammability test
- Dielectric strength test
For silicon O-rings, the SMI includes visual, dimensional, specific gravity, and silicon content tests.
Why Vaibhav Laxmi Industries
Vaibhav Laxmi Industries is part of a 40-year-old manufacturing group serving railways, power transmission, distribution, renewable energy, defence, highways, and infrastructure projects. VLI manufactures railway and transmission line accessories with a focus on project-grade quality, timely supply, and compliance with applicable specifications.
FAQs
- What is an Anti Bird Disk?
- An Anti Bird Disk is an OHE protection component fitted near railway insulators to prevent birds from perching and causing electrical faults.
- Is this product suitable for railway OHE?
- Yes. It is suitable for 25 kV railway and metro OHE applications.
- Is the Anti Bird Disk designed as per RDSO requirements?
- Yes. The product is manufactured as per RDSO SMI No. TI/MI/0059 Rev.3.
- What material is used?
- The disk is made from polycarbonate material with a silicon O-ring arrangement for fitment.
- Where is it installed?
- It is installed near stay tube, bracket tube, 9-ton, composite, and porcelain insulator arrangements in bird-prone OHE sections.
