The Land Transport Authority said it will require SMRT to carry out more stringent checks and replace the running rails earlier where necessary.
It issued a statement following the fourth incident of a rail crack that has occurred on the North-South/East-West Line in recent weeks.
LTA said it is concerned and is investigating the root causes of the incidents.
During a joint news conference by the LTA and SMRT to address the issue of rail cracks, SMRT said that it has completed ultrasound checks on all rail joints in the system, and no other defects have been found.
As some of the cracks are symptoms of an ageing rail network, more may be expected in the future. However, LTA said safety of passengers will not be compromised.
Deputy chief executive of the LTA, Chua Chong Kheng, said: "This is because the signalling system that we have is designed to detect rail cracks, and when the rail cracks, it will be treated as though the track is occupied. Therefore, other trains are prevented or not allowed to come in to that area."
LTA added that it is too early at this stage to determine if there is any underlying link or systemic issues that contributed to these four recent rail cracks.
LTA also said SMRT, which operates the North-South/East-West Line, has a system of running rail replacement similar to the approach adopted by operators in other cities -- whereby individual running rail segments are replaced when there are defects, or when the wear and tear for that rail segment warrants it.
But due to the recent incidents, SMRT will be taking various precautionary measures. These include accelerating its rail replacement programme.
Lee Ling Wee, senior vice president of rail services at SMRT, said: "In the past, we used to wait until the wear is 14mm before we replaced the rail. Now, instead of 14 mm we are shortening it to 12 mm.
"This means we are replacing it earlier, and that would mean additional maintenance efforts. We are in discussion with LTA for resources that we will need to increase our capacity for replacing the rail."
These resources include additional workshops to pre-fabricated rails.
SMRT said it has identified 40km of rail which need to be replaced -- the Nort South-East West Line has a total of 400km of rail.
Mr Lee added: "If we do not increase our capacity, it may take up to five years to replace the rails, but if we do increase our capacity, we are hoping to reduce it to two years."
LTA said that although the rail network is ageing, a complete overhaul is not necessary.
Mr Chua said: "Now, because the rails do not wear at the same limit throughout the whole railway, some stretches will wear faster -- for example at curves. So therefore, the replacement must be done on a basis where there are instances of the wear limits.
"The other occasion where rail is required to be changed is where there are defects that are found. For example, where there are cracks or corrugations on the rail head or the rail surface."
The LTA said it is monitoring SMRT's remedial actions very closely. It is stepping up audits on SMRT's maintenance works -- up from monthly to fortnightly -- to ensure checks are done thoroughly.
LTA will focus its audits on the track curves, as the recent rail cracks have occurred along such stretches.
To better determine what further measures can be taken to address the situation, LTA will be appointing an international trackwork specialist to assess the condition of the rail and to advise on possible changes to the operator's running rail maintenance regime.
SOURCE
Not very assuring eh? A crack track is not one to be meddle with. Any physical defect with it will cause a derailment if serious, and if there is such a day in Singapore's history, it will be very ugly judging by how crowded are our MRT trains. The authorities will have to take this seriously and keep a very close watch on SMRT.
No comments:
Post a Comment