This all details were given by Sabyasachi Sir...Kindly take a read and then say why not all the trains in india be LHB:
1. LHB coaches have an average speed of 160 kmph and a top speed of 200 kmph as compared to an average speed of 70 kmph and a top speed of 140 kmph in ICF coaches.
2. LHB coaches are more safer as compared to ICF coaches due to a number of reasons -
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* LHB coaches are anti-telescopic and does not turn turtle in case of a derailment.
* LHB coaches are made of stainless steel as compared to mild steel (which is a less ductile material and also heavier then stainless steel) in ICF coaches, this increases its shock bearing capacity in case of a mishap.
* LHB coaches have Disc brakes whereas ICF coaches have thread brake system hence shorter stopping distance.
* The coupling system in LHB coaches reduces the relative motion between two coaches and also prevents one coaches rising on the other in case of an mishap.
3. LHB coaches have a shorter wheel base thus improved ability to negotiate curves at higher speeds.
4. LHB coaches requires less maintenance (intermediate hauling every 5 Lac kms, and periodic hauling every 10 Lac kms) whereas an ICF coach has a shorter maintenance schedule (intermediate hauling every 2 Lac kms and periodic hauling every 4 Lac kms), so by the time an ICF coach is hauled 2 times, an LHB coach can still travel 1 Lac km extra. Thus reduced maintenance cost.
6. LHB coaches have axle mounted suspension system whereas ICF coaches have dashpot type suspension system.
ICF coaches have coil springs with dashpot level for primary suspension and springs on lower spring beam through hangers for secondary suspension.
Primary suspension system in LHB coach has coil spring with hydraulic damper and control arm and secondary suspension system springs directly mounted on the sides of frames.
This increase comfort in LHB coaches and reduces vibration, and also increases the safety because it has lower rolling effects.
Also ICF coaches suspension have a problem of oil spillage from the dashpot.
7. LHB coaches have a lower sound level of 60 Db as compared to 100 Db in ICF coaches.
8. LHB coaches have microprocessor controlled Air Conditioning system which automatically maintains the ambient coach temperature both during summers and winters.
9. LHB coaches have higher distance between the inner wheels which implies larger coach width and therefore the width of the side berth are wider then ICF coaches
All this equate to lower maintenance cost of LHB coaches, higher carrying capacity and manyfolds increased safety.
And biggest reason i think is development and change of face.
ICF coaches were based on a 1950's Swiss design, ‘Schlieren’ Swiss Car and Elevator Manufacturing Co."
1950 and now after 66 years , don't you think its high time to have our railways face change over.