Anti Monkey Climbing Device
| RDSO reference | TI/MI/0056 Rev.03 |
| Effective from | 27.11.2025 |
| Sheet material | Galvanized steel or aluminium |
| Sheet thickness | Minimum 22 gauge |
| MS flat | 40 × 6 mm galvanized |
| Device height | 1200 mm |
| Dia. for mast | Around 0.5 m |
| Dia. for yard portals | Around 0.9 m |
| Finish | Hot dip galvanized |
Standards & references
- RDSO SMI TI/MI/0056 Rev.03
- Effective 27.11.2025
- Traction Installation Directorate, RDSO
- Drawing TI/SK/OHE/ANTIMON/ RDSO/00001/08/0
- Galvanizing to ETI/OHE/13(4/84)
- Schedule of Dimensions 1676 mm BG, Rev. 2022
Vaibhav Laxmi Industries manufactures Anti Monkey Climbing Devices for railway, metro, and traction installation structures. The device prevents monkeys from climbing high voltage live structures such as OHE masts, portal uprights, and gantry mast uprights. It is manufactured in line with RDSO Maintenance Instruction No. TI/MI/0056 Rev.03, effective from 27.11.2025, issued by the Traction Installation Directorate, Research Designs & Standards Organisation, Ministry of Railways.
Monkey climbing on traction installation structures can cause electrical and mechanical failures, OHE tripping, equipment damage, traffic disruption, and loss of maintenance hours. VLI’s Anti Monkey Climbing Device creates a physical barrier that stops monkeys from gripping the structure while climbing.
RDSO SMI Based Design
The Anti Monkey Climbing Device follows the RDSO maintenance instruction for Prevention from climbing of Monkey over Traction Installation structures. The objective of the instruction is to minimize failures of traction installations caused by monkeys climbing high voltage live structures.
Key RDSO references:
- SMI No.: TI/MI/0056 Rev.03
- Effective from: 27.11.2025
- Issued by RDSO, Ministry of Railways
- Traction Installation Directorate
- Application: OHE, SP, SSP, FP, TSS
- Purpose: minimize traction failures
Product Purpose
The device is used at identified monkey-prone railway sections where monkeys climb traction structures and disturb OHE equipment. It helps reduce the risk of:
- OHE failures
- Electrical and mechanical faults
- Damage to high voltage live structures
- Railway traffic disruption
- Loss of material and man hours
- Unsafe access to traction structures
The working principle is simple: the arrangement prevents monkeys from getting a proper grip on the mast, portal, or gantry structure.
Applications
Suitable for use on:
- Railway OHE masts
- Portal uprights
- Gantry mast uprights
- TTC masts
- SP / SSP / FP / TSS locations
- Monkey-prone traction sections
- Railway electrification projects
- Metro electrification projects
Design Options
The RDSO instruction covers two suitable arrangements.
Cylindrical arrangement
The cylindrical arrangement uses a galvanized steel or aluminium sheet drum fixed around the mast or portal structure. The smooth cylindrical surface stops monkeys from gripping the structure. Main components include:
- Minimum 22 gauge galvanized steel or aluminium sheet
- 40 × 6 mm MS galvanized flat
- GI round head screws, 6 × 25 mm
- GI bolt 16 × 50 × 37 mm with nut and washer
- 17.5 mm diameter fixing holes
- Hot dip galvanized MS flats
Barbed wire frame arrangement
The barbed wire frame arrangement uses hot dip galvanized steel parts forming a protective frame around the mast structure. Main components include:
- Barbed wire
- MS flat 60 × 8 mm
- MS angle 60 × 60 × 8 mm
- Nuts and bolts
- Hot dip galvanized finish
Reference drawing: TI/SK/OHE/ANTIMON/RDSO/00001/08/0
Technical Specifications
| Parameter | Specification |
|---|---|
| Product | Anti Monkey Climbing Device |
| RDSO reference | TI/MI/0056 Rev.03 |
| Effective date | 27.11.2025 |
| Application | Traction installation structures |
| Suitable structures | Mast, portal upright, gantry mast upright, TTC mast |
| Arrangement types | Cylindrical drum and barbed wire frame |
| Sheet material | Galvanized steel or aluminium sheet |
| Sheet thickness | Minimum 22 gauge |
| MS flat | 40 × 6 mm galvanized MS flat |
| Fasteners | GI bolts, nuts, washers and GI round head screws |
| Screw size | 6 × 25 mm |
| Bolt size | 16 × 50 × 37 mm GI bolt |
| Fixing hole | 17.5 mm diameter |
| Device height | 1200 mm as per fabrication sketch |
| Approx. diameter for mast | Around 0.5 m |
| Approx. diameter for yard portals | Around 0.9 m |
| Galvanizing specification | ETI/OHE/13(4/84) |
| Finish | Hot dip galvanized steel parts |
Installation Notes
- The arrangement should be fixed above the number plate.
- Clamp size may vary as per mast size and TTC portal upright size.
- Indian Railways Schedule of Dimensions, 1676 mm gauge (BG), Revised 2022 with ACS, should not be violated.
- On structures other than portals on the track side, the projection of the sheet surface should not exceed 5.0 mm from the face of the mast.
- Records of location and date of provision should be maintained in the OHE depot for failure analysis.
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 project-grade fabrication, galvanizing, and supply capability for demanding outdoor installations.
FAQs
- What is an Anti Monkey Climbing Device?
- An Anti Monkey Climbing Device is a railway protection arrangement fitted on traction installation structures to stop monkeys from climbing masts, portals, and gantry structures.
- Is this device used for railway OHE structures?
- Yes. It is used on OHE masts, portal uprights, gantry mast uprights, and other traction installation structures in monkey-prone sections.
- Which RDSO instruction covers this product?
- The product is based on RDSO Maintenance Instruction No. TI/MI/0056 Rev.03, effective from 27.11.2025.
- What are the available arrangements?
- RDSO covers a cylindrical galvanized steel or aluminium drum arrangement and a barbed wire frame arrangement.
- Where should it be installed?
- It should be installed at identified monkey-prone locations or sections approved by PCEE. As per the RDSO instruction, it should not be provided at ATD locations.
- What material is used?
- Depending on the arrangement, the device uses galvanized steel or aluminium sheet, MS galvanized flats, GI bolts, nuts, washers, screws, and hot dip galvanized steel parts.
