INDIAN Railways is going for a special upgrade of Double Diamond Crossing in the Nagpur Station Yard. The measure is meant to enhance safety of rail operations plus increase the speed of trains’ movement in North-South, East-West and North-East rail corridors of the country, while negotiating the Nagpur Station. The Double Diamond Crossing is unique in the Railways, and Central Railway has awarded the contract to a German firm specialising in such critical works for undertaking the complete overhaul of track layout.

 

Officials in Engineering Department of Nagpur Division of Central Railway are working in tandem with their counterparts in Railway Design and Standards Organisation (RDSO) on the project, which is of critical importance from operations point of view. Rahul Agrawal, Sr Divisional Engineer (Central), said, the RDSO is examining the design submitted by the division. RDSO team has sought some data like movement of trains and same was shared. The design is expected to be finalised within a fortnight and thereafter, the work programme for undertaking upgrade will be finalised. Agrawalstated that, theDouble Diamond Crossing repair presents unique challenges for operations, as at Nagpur, as it has a 65degreeskew,thatrequiresspecial design approach plus specialised skill while undertaking the relaying of the crossing points.

 

As mentioned earlier, the specialty of the upgrade would be that the sleepers beneath it will be crafted especially for the diamondcrossing asper thenew design. They will be different from normal concrete sleepers thatareutilised for placing under the rails. Even the steel for crafting the plates that act as cushion below therailsto absorbshocksofpassing trains and provide stability torailwheelswould also be manufactured using special metals to ensure required strength and agility.Agrawal said, theGerman team came to Nagpur station a few months back and surveyed the double Diamond Crossing areausingTotalStation.After the survey, the maps were prepared and design for diamond crossings placement in the yard was finalised and submitted to the Railways.

 

The necessity for special upgrade arose as the flange of Goods trains were observed to be jumping the rail while negotiating the double Diamond Crossing.Soinvariably,thespeed of goods rake was reduced for safety but that means extra time for clearing the yard that hit the movement of long distance passenger-carrying trains.Therefore, Railway officials decided to go for special upgrade. A period of six months would berequired tocompletetheoverhaulproject atDoubleDiamond Crossing,assamewouldbedone in a piecemeal way, one point at a time to avoid total closure of Nagpur station.

 

 

DOUBLE Diamond Crossing means where two sets of tracksconverge at one place, creating four individual diamond formations, facilitating criss cross movement of trains on the cross.Seen from above, the design looks like a perfect diamond. But Double Diamond Crossing does not mean to indicate that all four cardinal directions of Indian Railways’ network converge at Nagpur. It’s simply a formation where a service branch line from the Nagpur Freight Yard crosses over the Gondia line. It connects the Howrah route coming from the East. The service line then joins the main line heading towards Delhi. Only three major rail lines meet at Nagpur Junction Railway Station, one from the East via Gondia, one from the North from New Delhi, and one heading South that later splits intoWestern route towards Mumbai and the other to Southern route towards Kazipet. The split happens at Chitoda, just near Sewagram, approximately 75 kms from Nagpur. Technical structure of a diamond crossing is a precise engineering work. Its function is to allow wheels from train on one line to pass over the rails of the intersecting line. Guard rails or check rails are positioned to guide train wheels securely through the crossing, while heel blocks maintain the proper spacing between running rails and guard rails. The track layout incorporates gaps atspecificpoints topermitwheelflanges fromcrossing trains to pass through. These gaps need careful maintenance since they create points ofimpact and vibration that cause accelerated wear.