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Movement of BOBRN Rakes Via UP Saranda Tunnel – Innovative Achievement On CKP Division of S E Railways

By on September 10, 2014

A landmark achievement has been added to the saga of successful operational improvements on Chakradharpur division of South Eastern Railways recently.

Chakradharpur division is a critically important division from Railway operations point of view with 750 RKM of track, out of which 268 RKM consists of Tatanagar-Jharsuguda section which is a part of Howrah-Mumbai trunk route, loading of 3800 EWWs per day (95 mt per year), average loco holding of 230-240 locos, average wagon holding of 11000 and av. interchange of 200 goods trains per day with adjoining divisions.

Main line section from Goilkera to Manoharpur is having a steep gradient of 1 in 100 as well as long tunnels in both directions requiring banking of freight trains.

Entrance of UP Saranda Tunnel- CKP end

Entrance of UP Saranda Tunnel- CKP end

Existing 472 m long Up tunnel was constructed in 1891.  The section was electrified on 25 kV in the year 1962 and pedestal insulator type OHE cantilever fixing arrangement was provided inside the tunnel.

With existing OHE fixtures and available clearances, UP tunnel was fit for movement of all traffic except for any type of ODCs and BOBRN/Container rakes.

On an average, 60 Nos. of BOBRN rakes are moved in a month in either direction. Due to infringement restriction, daily 2 to 3 UP direction BOBRN/Container rakes had to be run via down line affecting the flow of traffic.  Average rake detention was to the tune of 2.45 hours per rake.

To ensure that wagons/loads do not infringe the Up tunnel, an ODC profile gauge has been provided at Goilkera station on UP line track.  In case of any ODC, the gauge limit switch gets operated and UP starter signal goes to danger, thus avoiding the possibility of any ODC rake movement through UP tunnel.

A study was undertaken in early 2013 by CKP division for removal of infringements, where-in Tunnel Profile, Maximum Moving Dimensions, OHE Structures Profile, Track Profile and BOBRN profile were examined in detail.  A joint survey by TRD, Engineering and C&W departments was carried out by taking a BOBRN wagon inside the tunnel under the supervision of Branch Officers.  According to the joint survey, it was feasible to run the BOBR/BOBRN rakes through UP Tunnel by carrying out OHE structure modifications.

The type and profile of OHE structures provided in the existing tunnels on other Railways was studied and it was decided to adopt the OHE structure arrangement provided on the K-K line tunnels.

Methodology of fixing OHE cantilevers, by epoxy grouting on tunnel face, was adopted eliminating the requirement of pedestal insulators. During joint trial it was observed that it was possible to get clearances for running class ‘B’ ODC.

Drawing of old cantilever arrangement

Drawing of old cantilever arrangement

View of old cantilever arrangement

View of old cantilever arrangement

A total of 17 pedestal type OHE cantilever structures were there in the UP tunnel.  All 17 structures have been modified by the division departmentally by availing small duration blocks and without affecting the movement of traffic. A joint trial, by running a BOBRN rake, was conducted successfully in Oct’13. BOBRN and Container rakes are now being run via UP tunnel on regular basis.

Drawing of new cantilever arrangement

Drawing of new cantilever arrangement

View of new cantilever arrangement

View of new cantilever arrangement

This innovation resulted into substantial improvements in train operations in the critical Goilkera – Manoharpur section as daily detention of 2 to 3 BOBRN/Container rakes for an average of 7.00 hrs. per day has been avoided.  This has resulted into direct savings of Rs. 7 lakhs per day (Rs. 25 crores per year) apart from increase in the section capacity by about 5% and improved fluidity of the section.

An operational constraint existing for last about 50 years has now been successfully removed by CKP division of South Eastern Railways.

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  1. Gurmeet says:

    Please tell the Exact medical category for je drawing estimator civil ?It is office work related job

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