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Indian Railways (IR) has come a long way since the beginning in 1853, and some very bold  and innovative steps, especially since 2015, are being taken to bring up the Railways to world  class standards. 

For the first time in the history of IR since 1947 we have a Technocrat as the Railway  Minister who is ably guided and backed up by a decisive and visionary Prime Minister. 

Decisions such as complete electrification of railway traction, construction of dedicated  freight corridors, makeover of hundreds of railway stations, Testing Track in Rajasthan, RRTS  in Delhi area, installation of bio-toilets, introduction of Semi High Speed Vande Bharat trains  are positive steps in the right direction. But more importantly, the speedy implementation is  the most welcome change from the rather slow pace prior to 2015. 

High Speed Railway in India 

The maximum speed of trains in India had been pegged at 60 mph (96.6 kph) from the very  beginning, with the exception of the “Deccan Queen” inaugurated on 1st June 1930, which did  run at an average speed of 100 kph between Mumbai & Karjat thus indicating a maximum  speed of about 75 mph (120 kph) at least for part of the journey. As a matter of record the  specifications of the electric locomotive intended for this service called for a maximum speed  of 87 mph (140 kph).  

The first ever trial to explore the possibility of introduction of high speed train service were  conducted during a period from November, December 1955 to January 1956. The results were  published in .Dynamometer Car Report No 54. Nothing much came out.  

The second set of trials were conducted during late sixties and reported in RDSO report  C&M 1. The result of the trials was, first the introduction of “Rajdhani Express” trains with  track quality getting improved and as coaches and locomotives with higher speed potential  were made available, introduction of “Shatabdi” and “Gatiman” express trains running on  some specific routs with maximum speeds of 130/150/160 kph. 

Vande Bharat Express 

In order to introduce a High Speed train based on the principle of “Electric Multiple Unit”  rather than that of a train hauled by a locomotive design work was undertaken as “Train 2018”  later changed to “Train18”. 

The name of the train was changed to “Vande Bharat Express” in recognition of the total  indigenous design and manufacture under the Prime Minister’s “Atmanirbhar Bharat” vision.  The inaugural run was flagged off by the Prime Minister on 15th February 2019 from New  Delhi to Varanasi. Since then several Vande Bharat trains with improved designs have been  introduced by Indian Railways.  

The maximum speed achieved by a Vande Bharat train stands at 180 kph a little less than the  speed of 184 kph achieved by the WAP 5 locomotive in 1997. 

While all these efforts are laudable the author has some concerns regarding the technical  standards adopted by Indian Railways and these relate to: 

1. Ride Index 
2. LHB (Fiat) Bogie 
3. Casnub Bogie 
4. Track Standards & Track Quality 

Ride Index  

Ride Index denotes the quality of ride of a railway vehicle when in motion and is a numerical  figure on a hyperbolic scale of 1 to 5. while No 1 denotes appreciation as “Very Good” No 5  denotes appreciation as “Dangerous Likely to Derail” as generally understood. IR specify a  RI of 3.25 as preferable for passenger coaches of main line service and EMU and 3.5 & 4.0 as  limiting values respectively. The acceleration values specified are 0.30g and 0.35g as  preferable and limiting.  

The value of 0.35g exactly corresponds to the value as “Chartet’s Formula”, a border line  case. It may be noted here that a normal human being can tolerate acceleration levels between  0.8 m/s/s and 1.3 m/s/s, the average value being 1.0 m/s/s which works out to be “0.102g” 

Readers can draw their own conclusion. It is also noted that while issuing a “Speed Certificate”  Indian Railways never mention the value of Ride Index, but say that “the ride is satisfactory” 

Railways need to be more specific by mentioning the RI while issuing Speed Certificate.  LHB (Fiat) Bogie 

The omnipresent “ICF All Coil” bogie suspension of passenger coaches did not have a higher  speed potential of more than 130 kph and that too on specially maintained track,  

IR therefore went for a new coach design and improved suspension system. Coach designed  by LHB paired with bogies from FIAT based on the principle of a main frame without the  head stocks which reduces the rotational inertia of the bogie thereby reducing the “yaw”  oscillations. 

First 24 coaches were tested for ride quality and the results were rather disappointing and  fitment of “Yaw Dampers” is reported to have improved the ride quality.  

However in author’s view a very important aspect of a bogie design was totally ignored and it  is the ratio of bogie wheel base to track gauge. A perusal of various bogie designs of world  railways reveals that this ratio happens to be around 1.75 / 1.8 and sometimes even 2.0. 

Larger wheel base reduces the tendency to “Yaw” 

However in case of FIAT bogie it works out to be 1.5274 as the design was just adjusted for  difference in the standard and broad gauge. 

It is noted that the wheel base of Vande Bharat bogie is increased to 2,700 mm as compared  to 2,560 mm of FIAT bogie, although for different reason. It is also noted that the speed  potential of Vande Bharat is 200 kph. The ratio is 1.611 for Vande Bharat bogie. 

However it is rather late in the day to consider adoption of a new bogie with larger wheel base.  Perhaps IR can consider fitment of Vande Bharat bogie to LHB coaches. 

Casnub Bogie 

Casnub bogie was selected to replace the “BOX” bogie and the main consideration as stated  seems to be ease of maintenance. The design based on American “Three Piece Truck” bogie  was a subject of controversy from the very beginning with many zonal railways reporting the  damaging effect it had on track structure. Several derailments were also reported forcing  RDSO to undertake corrective measures such as fitment of lower spring plank and interposing  elastomeric pads between the axle bearing and the side frame. RDSO has published a small  booklet titled “Taming of The Casnub” written by Mr K B L Wadhwa and one is left  wondering why the bogie had to be “Tamed” if the selection had undergone a careful scrutiny. 

In author’s view selection of a bogie which had a large un-sprung mass in the form of side  frames was in itself a wrong decision. Especially when an excellent design as Y25 bogie was  also in the running. Comparison with the use of American Railroads is rather misplaced. US  railroads employ high axle loads but then the track structure is much more robust than that  of Indian Railways. 

That large un-sprung mass has a detrimental effect of track quality has been has been a  universally accepted fact. The damaging effect of Casnub bogie on track structure has a  cascading effect, greater the damage rougher is the ride, rougher the ride more is the damage.  IR operate world’s most intensively worked network and as such it is rather difficult to obtain  “Power Blocks” of adequate duration for the track maintenance, non withstanding what the  manual says. Such a situation is not exactly conducive when the aim is to operate trains at  higher speeds than hereto attempted. 

Selection of “Y25” bogie which has a low un-sprung mass and caters to both loaded and  empty conditions of the wagon would have been a better choice. As a matter of fact such  bogies are the mainstay of European railways.  

Track Standards & Track Quality  

Both reports (1955/56 and 1969) of the trials for introduction of High Speed trains in India  have commented on improvement of track quality and the maintenance standards for the track  to be were according to RDSO report C&M 1. Indian Railways Permanent Way Manual lists  out standards for various track parameters such as Alignment, Unevenness, Twist, Gauge etc.  During a long and pleasant association with IR, it has been the author’s observation that the  standards are set more on “what can be achieved during normal course of working  without any additional efforts” rather than set the standards higher than present and then set  about achieving the same. There is also a use of terms such as “few occasions”, “isolated  instances” without actually specifying these “occasions” or “instances” with reference to time  or length units. 

It is noted with satisfaction that with the redrafting IRPWM and publication in June 2020  some of the issues have been addressed to and there is a substantial improvement in terms of  values of deviation and also adoption of longer chord lengths for measurements. The  standards are now set for tracks according maximum allowed speed but these again restrict  the operation of High Speed trains to a few routes and even these routes operate at a much  higher capacity than designed thus hampering through running of high speed trains. 

However it the author’s apprehension that, although the objective is laudable, whether the  track can be actually maintained to desired standards given the damaging effect of “Casnub”  bogie and difficulty in getting power blocks of adequate duration. 

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