[norhog]

This is a good effort. I applaud it from the bottom of my heart.
For a country like ours, economically not so good, bonded by government bureaucratic shackles any improvement should be welcome.
I understand that this double decker coach is not new, it is only the air spring.

So who is the supplier of this new air spring?
Is it made by RCF Kapurthala?

This is the KAIZEN philosophy.
Small incremental improvements. The T-18 was one big step, no doubt.
If these rail factories continue this process of incremental improvement, albeit at a quicker succession it will be good for the country as a whole.

We must applaud this and encourage it. On part of government by encouraging more such designs.
We as citizen, ensuring this is not miss-used or damaged, by ourselves (We Team BHPians would never do it, I am sure) and if we see others do it we must stop it as much as possible in our capacity and record and shame the miscreants.

[sunilch]

Originally Posted by ninjatalli

To the experts a question - I always assumed the railway tracks played a bigger role on enabling faster travel speeds, remember reading some recent update on tracks in Northern & Western Karnataka being upgraded to support faster speeds. Is the 160 kmph rating apply more from a comfort aspect (suspension, etc.)?

Not an expert here but from what I know and have read - tracks is one part of the equation in enabling fast train travel. The major bottleneck for India is actually the signalling technology and 'restricted access' tracks (the lack of it).

Signalling tech needs a giant leap across the country before our average speed can be increased across the board. 'Restricted access' tracks needs no mention I don't think that is easy to implement in India but the first part is critical.

[mvadg]

Originally Posted by vigsom

Sharing my experiences with seats on the current Double Decker coaches that have been doing duty since 2013. Although the coach looks very bright and airy inside, the seats, built by Sutlej, leaves a lot to be desired :

* The worst seats I've ever sat in
* Seat back was no wider than 1.25 times the length of a Reynolds 045 pen
* Seat bottom used to sag forward and that would make travel a pain post 30 minutes
* Seat back would recline no more than 30 degrees
...

Just thinking about the "double decker" makes me cringe. Now I have to be extra careful about avoiding this type of coach for all the reasons you've mentioned above.

In addition, all of what others have stated about the space, riding too close to the platform, the dust and the dirt, hold true. I wish our railway monopoly could hire better engineers for our "Atmanirbhar" fantasies or at least be forced to conform to international standards. Sorry, I don't want to pay more and I demand that I at least get what I'm paying for, which is definitely something much better than this piece of junk.

[sandeepmohan]

I appreciate RCF's efforts to make this coach fit for higher speeds. What I don't like is the interior and what IR think in terms of squeezing as many humans as possible into a coach. It has got to the point of being uncomfortably close to your co passenger. There is zero shoulder room and next to no legroom. The seat base is so short that the only support you get is for your rear end. There is no under thigh support. I prefer taking the standard 3+2 configuration AC Chair car service over a double decker any day.

[Ultim8]

Ah! This double-decker train reminds me of a positive experience I had while I travelled alone once in the double-decker train from Chennai to Ambur after I completed my 11th grade. I had to settle for lower deck due to lack of availability of upper deck seat during the time I booked the ticket. Nevertheless, it was a great experience for me to travel in that train.

I understand people feeling uncomfortable with the relatively narrow seats compared to that of conventional trains, but surprisingly I had no such issues regarding comfort while traveling. The noise insulation was impressive, considering my seat was 3-4 compartments away from the generator & the engine.

The double-decker trains (like other trains) in SR travel at 90-100 km/h with occasional peaks of 120 km/h due to the limitations of compartment dynamics & railway tracks, as mentioned by the OP, despite the engines having top speed of 160 km/h. My journey from Chennai to Ambur took only around 2.5 hours with stops only at Arakkonam & Katpadi in between.

[vredesbyrd]

Mod Note : Please do NOT post messages that add little or no informational value to the thread. We need your co-operation to maintain the quality of this forum. We advise you to read the Forum Rules before proceeding any further. Request to post ONLY when you have something substantial to add to a discussion.

[peyyala]

I wanted to travel on the double decker train, specifically on the upper deck. I got the opportunity last year when I took the blr Coimbatore express Beyond the excitement of the first 5 minutes, I really regretted the experience. Narrow seats, claustrophobic interiors, non operating vending machines were some of the cons. The railway engineers really need to go beyond increasing customer capacity and take a hard look at a improvement in customer comfort and hygiene.

[tharian]

I wonder what they did to make the coach safe to run at 160kmph.

I travelled in the SBC-MAS DD once and although the line was approved for 110 and 120 which are the speeds Shatabdi does, DD never crossed 90-100 kmph which my guess is because of the double deck and also the track conditions.

[Dieseltuned]

Poor seats is one of the major reasons most of the double deckers run half full. Even on the high demand BCT-ADI route most of the days you can get same day reservations. As rightly said the railway engineers had only one motto to increase capacity without an iota of thought about comfort or aesthetics.

High speeds remain a dream in India due to non secured tracks, apart from bovines to elephants to the most stupid living being on planet (man) have free and open access to the tracks.

[torquecurve]

For a train to run at 160 kmph there are multiple requirements that needs to be satisfied
1- Track capability : the tracks have to be rated for 180 kmph (160 plus margin). This includes the metal track, the sleepers that hold them, the rock below etc.
2 - Section MPS and length of section - if a section is 100 kms, a 500 mtr train will use about 20-25 kms to
Accelerate to 160. Then if next section is rated for 100kmph the train has to decelerate about 10kms before the section at least. So only about 60-70 kms it will be at 160 that means about 25-30 mins. This is with electric traction and powerful engines like WAP5.
3 - Section Clearance. Typically IR runs trains with a gap of 5-10 kms on high traffic routes. This means that if a train preceding this high speed train is in the high speed section at 120 when the rapidly accelerating 160 kmph, you have to ensure section clearance by the preceding train and safety gap is maintained.
A key challenge is that we use the same tracks for goods trains which accelerate slower and have lower top speeds also. Add to that single line sections and you know why we don’t run at 160 though we can.

Coming to the design of the train -
Double deck trains are meant for day journeys, typically 8-9 hours max. These trains currently use LHB coaches (8-9) plus two power coaches. Reason is axle limit load for the puller loco. Now if I am able to pack 30-40% more passengers in the same axle load (and axle count) with the same level of safety! Bang I have a double decker train.

In terms of passenger comfort, let me tell you an anecdote. The ones who have used coin PCO phones will remember that it was easy to trick the phone using washers of the same size as a 1/- coin. Incidentally the washers were 3rs a dozen or so. Also look at a one year old Zoom car. In India we don’t respect the rules, have no or limited civic sense and above all we don’t respect what is not ours. So all the effort that railways will put will be nullified by US!

[Romeo_Mike]

Originally Posted by AirbusCapt

Why is the finishing so shoddy on these coaches?

I have noticed the same as well. And ICF Chennai products are no different either. Would lead one to believe IR does not hire people for denting/painting and the task is managed part time by the cleaning staff only. The quality of the workmanship, quite frankly, is no better than sweeping the floor!

[torquecurve]

Originally Posted by AirbusCapt

Why is the finishing so shoddy on these coaches? Can't they manage to get a smooth body and paint finish on them? Are they still painting using brushes and a ladder?

[quote=srishiva;4937582
Doesnt really exude quality. Maybe its the metal presses they use and also the painting. [/QUOTE]

Originally Posted by dileepcm

Everything from top to bottom looks horrible to me. Paint scheme is not only boring but also lacks finishing. So are the interiors. First interior photo above looks like it's already many years old. Panel gaps on roof, cable ties for supporting wiring etc. makes a high statement of how unprofessional things are when it comes to coach design and building.

Originally Posted by Romeo_Mike

I have noticed the same as well. And ICF Chennai products are no different either. Would lead one to believe IR does not hire people for denting/painting and the task is managed part time by the cleaning staff only. The quality of the workmanship, quite frankly, is no better than sweeping the floor!

Not defending the RCF which made this. But this type of ‘warped’ look is very common in products where a thin sheet of metal is wrapped on a subframe. You will see this in ships as well (stealth warships!) attached a couple of pictures. From whatever little knowledge I have of this it helps the metal flex as it is exposed to varied temperatures and pressures as well.





(Picture credits - respective owners)

About the panel gaps, hanging wires etc - this is a test bed. Maybe a one off - such construction will help to make changes easier when required in testing.

[vharihar]

If not the body exterior finishing, atleast I hope the functional reliability is good. Unlike what the following 9-mth old article has to say, which is terribly bad to read:

https://timesofindia.indiatimes.com/...w/74298092.cms

[Romeo_Mike]

Originally Posted by torquecurve

But this type of ‘warped’ look is very common in products where a thin sheet of metal is wrapped on a subframe. You will see this in ships as well (stealth warships!) attached a couple of pictures. From whatever little knowledge I have of this it helps the metal flex as it is exposed...

Don't think that is a design aspect, not sure about ships but not on trains atleast. I remember being mighty impressed with the fit and finish of the newly introduced LHB coaches on the Mumbai Rajdhani when I spotted them for the first time in BCT back in the day. Wish I could dig up a pic but couldn't find one online.

Again not sure if those were the initial batch imported from Germany or were produced in India. My best guess is the current fit and finish of the same made in India LHB coaches is a conscious decision by IR to reduce cost. I hear each coach costs ~ 3 Cr. INR

[torquecurve]

Originally Posted by vharihar

If not the body exterior finishing, atleast I hope the functional reliability is good. Unlike what the following 9-mth old article has to say, which is terribly bad to read:

https://timesofindia.indiatimes.com/...w/74298092.cms

To be Brutally honest this is a load of BS. Sorry.

Let me break it down (I am typing on my phone so won’t be too detailed)

The LHB coaches use a FIAT bogie which run on Timken CTBU (Cartridge Taper Rolling Bearing Unit) Type of Bearings. These are ‘prebuilt’ bearings with grease etc already ‘in the bearing’ as opposed to the ICF coaches which used single roller open bearing.

About Air Springs - FIAT bogies used in LHB coaches always had air springs. The ‘primary spring’ is actually supported by two Coil Over springs which are then connected via the top part of the bogie to the wheel set. This introduces triple redundancy in load bearing.

Hot Axle - is possible. But it has a lower likelihood of it happening on CTBU bearings simply because the design life is higher.

Also in 5 years there will be at least 10 minor checks (Marshalling yard check) and 2 deep checks (Depot check). With the older rolling stock this was easy - tap check, followed by greasing. Whereas with these bearings it is ‘replace - recondition - replace’ meaning instead of checking. The bearing is removed and replaced with a new / reconditioned bearing, the old bearing is sent for reconditioning and so on. The older coaches needed higher maintenance for the axles as the greasing and stuff has to be done every 2-3 months. With the introduction of LHB coaches this maintenance requirement has gone down! Also bearing manufacturers and traditional supply lines were replaced with newer suppliers.

So if in 5 years and so many checks - the bearing will be replaced at least once!

This seems to be a ‘motivated’ news item. Many reasons - newer suppliers, lower manpower requirements etc etc.

If you get a chance do read about how the Train18 team was put under the scanner for ‘not following due process’. There is a lot of infighting that exists.

Originally Posted by Romeo_Mike

Don't think that is a design aspect, not sure about ships but not on trains atleast. I remember being mighty impressed with the fit and finish of the newly introduced LHB coaches on the Mumbai Rajdhani when I spotted them for the first time in BCT back in the day. Wish I could dig up a pic but couldn't find one online.

Again not sure if those were the initial batch imported from Germany or were produced in India. My best guess is the current fit and finish of the same made in India LHB coaches is a conscious decision by IR to reduce cost. I hear each coach costs ~ 3 Cr. INR

Please see this coach used by AMTRACK. finishing is similar

The LHB coaches in the past were built on a three layer system. Inner surface with insulation, a corrugated panel longitudinally mounted on base frame and outer frame with insulation/damping again (rubber). This leads to the low NVH of these coaches. The outer panels were 90mm steel plate.
Newer LHB Coaches don’t have the corrugated panel which is replaced with tubular section proving better rigidity and anti telescoping in crash. Also the tubular section allows for running of utility lines. The outer panels are 60mm stainless steel. Damping is now done using foam panel instead of the rubber pasted on the metal sheet. This allows single later of insulation instead the two layer insulation in past and improves resonance and temperature losses.
The newer LHB coaches are lighter, more rigid, better in terms of crash safety, better insulated.

For anyone travelling by LHB coach - Don’t be in the loo too long - that’s a part of the ‘crumple zone’

Most of this information is available opensource - RDSO website is a good place to start