3-6 Positioning Tube (3-6A Hook Type / 3-6B55 Double-Eye)
Backbone tube of the positioning device, carrying bracket, eyes and supports from the inclined cantilever.
Specifications
| Model | 3-6A (Φ34/Φ48), 3-6B55 |
|---|---|
| Drawing No. | 3-6A |
| Standard | TB/T 2075.3-2024 — Part 3: Limit-type positioning devices |
| Design Speed | Positioning backbone for ≤250 km/h (3-6A steel) and 250–350 km/h aluminum systems (3-6B55) |
| Materials | φ34×2.5 / φ48×3.5 galvanized steel; φ55×6 aluminum alloy 6082-T6 |
| Installation | Hinged to the registration eye on the inclined cantilever, carrying the positioning fittings |
The 3-6 positioning tube is the backbone member of the positioning device: hinged at one end to the registration eye on the inclined cantilever, it carries the registration bracket, eyes and support fittings along its body and delivers the contact wire loads from the locator back into the cantilever structure. Its length is selected to match the mast assembly dimensions.
Two variants cover the systems: 3-6A hook type in φ34×2.5 or φ48×3.5 steel tube with a connection hook at the end, and 3-6B55 double-eye type in φ55×6 aluminum alloy (6082-T6) with cast aluminum double-ear sleeve — matched to the φ70 aluminum cantilever and 3-5B70 registration eye of 250–350 km/h aluminum systems.
Design Features
- Φ34 / Φ48 steel (3-6A) and φ55×6 aluminum (3-6B55) cover the speed classes
- Good tube straightness keeps the registration bracket sliding smoothly for setting
- Interfaces match registration eyes, brackets and support fittings
- Anti-corrosion finish for long-term outdoor service
The product is manufactured under CRCC railway product certification and an ISO 9001 quality management system, with incoming material inspection, in-process control on critical operations and batch-by-batch final inspection before delivery.
Henan Chuangwit Railway Equipment Co., Ltd. supplies this locator with selection calculations, matched fittings and site technical guidance for traction power projects. The registration bracket (which carries the locator), registration eyes, support fittings and related fittings are clamped along the tube; the tube itself hinges to the registration eye on the inclined cantilever. The 3-6B55: a φ55×6 6082-T6 aluminum tube with cast aluminum double-ear sleeve, matched to the φ70 aluminum cantilever family of 250–350 km/h lines. By the mast assembly dimension of the OCS cross-section drawing — the tube must reach from the inclined cantilever eye to the registration point with the designed offset. 3-6A steel tubes (φ34×2.5 / φ48×3.5, galvanized) serve lines up to 250 km/h; the aluminum 3-6B55 reduces weight and matches the aluminum cantilever system for 250–350 km/h duty.Frequently Asked Questions
What hangs on the positioning tube?
Which tube for high-speed aluminum systems?
How is the tube length chosen?
Steel or aluminum — how do they differ?
Performance
Operating Conditions
Outdoor service at OCS registration points on mainline, high-speed and station structures, subject to suspension, wind, ice and dynamic pantograph loads as defined by the OCS design.
Mechanical Performance
Tube transmits locator loads to the cantilever; straightness supports bracket adjustment along the body.
Applications
250–350 km/h Lines
3-6B55 aluminum tube for high-speed systems.
≤250 km/h Lines
3-6A steel tubes for conventional classes.
Station Yards
Lengths matched to mast assembly dimensions.
Standard Assemblies
Carries the TB/T 2075.3 fitting family.
