During my time with VolkerRail they were one of the first companies to look at how LEAN can be applied to the rail industry.
This meant starting from scratch, there is no one to copy.
Below I have tried to help you understand what type of issues come to light when looking through ‘LEAN Goggles’ at the track renewals process.
Excavation of spent ballast
When excavating the old ballast we start at one end (usually) and work through to the other. We may use one or two machines to do a rough dig, then use one machine with a dozer to trim to the finished level.
This causes waste, waste in the Lean sense rather than the more conventional sense, i.e. those activities in the process not adding value. For the example described above the following wastes exist:
Reworks as a result of a defect – using the dozer and another machine to complete the dig means we are effectively doing the dig twice.
Unnecessary motion – each time the machine working with the dozer lifts a bucket of spoil to the train it is unnecessary if the first dig had been done properly.
Inventory – the area of the dig between the first rough dig and the trim can be considered to be inventory, this area is not having any value added to it.
Defects – associated with the above point we don’t know if the rough dig is right until the dozer gets to it, perhaps the area has been over dug and is now too deep?
Inventory again – the area behind the dozer does not get any ballast dropped on it until the dozer has gone all the way through.
Transport – the dozer now needs to travel all the way back to the beginning, this is waste as is the fact the first area to be dozed has been waiting to be worked on again.
You are probably reading this thinking, ‘Yeah but the train needs to move.’, or ‘We cannot afford to have two dozers’, or ‘It would be too slow to do the whole dig in one go.’ Well yes, that is how it is now, but how could it be in the future?
Could there be a machine that can complete the dig in one pass? Could we have new trains that can take away old ballast and bring in new ballast at the same time?
This is what is meant by the term ‘LEAN Goggles’ when one learns to use these one sees things in a completely new way. It can be quite frightening.
LEAN in action
One example of attempting to improve how the track renewal process works can be seen in the experiments using a Road Planer to excavate spent ballast.
The trial was used to understand if the machine could improve the speed and quality of the excavation phase of a track renewal project. Excavation had, for a long time, been a process which took a large proportion of the renewal possession, and the quality was variable at best.
The planer produced a very good quality cut but with only one machine the work rate was not perceived to be great, especially considering that several passes were required to achieve the correct excavation depth and width.
So why has this idea not been taken further? Perhaps there exists a reluctance to change, perhaps without constant pushing people do what they have always done. But perhaps there is no real data to prove which technique is best. We need to have real data to compare outputs and quality.
We also need to have the vision to enhance the existing equipment to make it do what we want to do more precisely. The next steps for the planer were quite obvious, work them in multiple, or use a wider drum and some changes to the chute to stop it betting clogged in very poor ballast conditions.
Link the laser levelling equipment to the hydraulics, so the idea is not dead, just waiting to be taken forward again.
This solution does not provide a solution to all the wastes listed above, but perhaps it forms part of the new solution, however that may look.
This post was written by Steve JohnsonTags: Continuous Improvement, Derby IMT, Integrated Managament Team, Lean, Network Rail, Steven Johnson, track renewals