Executive Summary – Permanent Way
Section : Hyderabad Metro Rail Project
Gauge : 1435 mm
Length : Corridor 1 -28.87 Km, Corridor 2 -14.78 Km, Corridor 3 -27.51 Km totaling to 71.16 Route Km.
- The permanent way consists of rails of section UIC 60, grade 1080, Head Hardened for complete main line and rails of section UIC 60, grade 880 for depots which shall be 18/13 meters long. Restraining rails of section 33 C1, grade 880 of 13 m long shall be provided for all curves of radius less than 190 m.
- All the running rails shall be continuously welded by Flash Butt Welding/Alumino Thermic Welding processes. The track on Main Line shall be laid on plinth type ballastless track with rails discretely supported by ballastless fastenings on Concrete plinths of M 35 grade.
- The ballastless rail fastenings are spaced at 650 mm c/c on viaduct and ramp with 1 in 20 rail inclination. The track in the depots shall be laid on ballasted track with Standard Gauge Monoblock PSC Sleepers with the density of 1540 sleepers per Km using ERC MK III fastening system and GFN Liners of indigenous make and 65 mm stone ballast with minimum cushion of 250 mm under the sleepers.
- The cushion shall be 300 mm for test track. Portion of depot track shall also be laid as embedded track with special base plates and also on plinth with ballastless fastenings to suit the requirement.
- All the turnouts to be negotiated are with 1 in 20 rail inclination. 1 in 9 switches of radius 300 and 190 for the main line and 1 in 7 switches of radius 190 in the depot with Zu 60 profile (thick web) shall be used.
- Weldable CMS crossings shall be used on main line and depots and shall be subjected to explosive depth hardening to provide minimum hardness of 340 HBW. Ends of all tracks on the main line and as well in the depot like washing lines, stabling lines, workshop and inspection bay lines shall be provided with Friction type Buffer Stops.
General Criteria for Tracks
Max. operating speed
||Max. axle load, loaded condition
Normal / desirable Limit
||Sharpest vertical curve radius
Sharpest horizontal curve radius
120 m (main line track)
90 m (depot track
||Traction power collection
||Overhead Catenary system (OCS) at 25kV(AC)
Rails shall be used for traction return current.
||Inclination of Rail
||1 in 40
||Wheel tread profile
||UIC 510-2 (S1002); to be interfaced with Rolling Stock Contractor.
||UIC 60 (861-3)