Video showing sequences of Factory Acceptance Testing of Next Generation Track Research
22 March 2021
•Cast block heaters
•Measurement of longitudinal profile of weld repair (Stand-alone unit)
•Operation of brakes of DDR unit:
•Positioning machine over identified defect
•Clamping of DDR Unit to rails: Location and design of clamps
•Rail Profile measurement: Existing rail profiles on either side of area to be repaired will be measured. Measurement technique will be explained.
•Excavation/Milling out of defect: Demonstration will be for excavated dimensions of 100mm (L) X 10mm (D) x Full head width.
•Profile measurement: Measurement of excavated profile to confirm width of welding bead oscillation.
•Weld restoration: Restoration will be undertaken using three layers + a sacrificial layer.
•Preheating: Rails are preheated to 60-800C using the cast heating blocks that are placed manually over location of the defect – automation of heater placement will be considered as part of follow-up project.
•Measurement of temperature: Automated spot measurement of temperature within excavated cavity and adjacent parent rail.
•Automated cutting of welding wire
•Automated peening after each layer of weld deposition
•Automated forced air cleaning of deposited and peened layer
•Automated repetition of weld deposition and supporting tasks to deposit two further layers and a sacrificial layer.
•Automated measurement of welded profile height to establish reprofiling requirements
•Reprofiling of repaired area: Automated computer controlled milling (rough & finish profiling)
•Profile verification – automated 3D profile measurement to show blending of repaired area with adjacent rail
•Measurement of linear profile to demonstrate compliance with specification – this is a follow-up operation as the DDR unit would need to be moved to permit measurement over the required 1m span.
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