EVALUATION OF THE PLASMA TORCH. STUDY OF OPERATIONAL TESTING AND EVALUATION OF AN ARC PLASMA GENERATOR AS A MEANS TO IMPROVE WHEEL-RAIL ADHESION
Effectiveness of the d.c. are plasma generator as a tool for improving wheelrail adhesion was measured. Two torches per rail were found very effective in eliminating low adhesion areas. Generally, adhesion values of 0.1 to 0.2 were increased to nearly 0.3. More specifically, adhesion corresponding to the 2% slip risk level, averaged over all tests in the speed range up to 30 mph, was increased from 0.19 to 0.29. Significant improvement of adhesion was found up to six hours after treatment with the plasma torch even though climatic changes had brought about changes in the adhesion of both control and test sections. Over longer periods, large numbers of freight and passenger trains distribute fresh contamination over the test and control sections thereby changing the identity of the sites. The power used was increased with the square root of speed up to 15 mph when it totalled 60 kw for both rails. Above 15 mph the power was held approximately constant at 66 kw. Constant power operation results in adhesion increases which are significant but less than would have been obtained if power had been increased. The power level used in all the trials was such that no damage could occur to the rails. Experiments in the laboratory have shown that even with much greater plasma powers the mechanical properties of rail steel were unaffected; this provides a high level of operational safety should the power control system malfunction. With this equipment the problem of wheel slip on starting, for heavily laden freight and passenger trains, can be confidently said to be overcome.
British Railways Board Research DepartmentElectrical Research Division
- Dobbs, D J
- Publication Date: 1970-1
- Pagination: 59p* p.
- TRT Terms: Adhesion; Coefficients; Dynamics; Rail (Railroads); Train track dynamics; Wheels
- Old TRIS Terms: Adhesion coefficient; Plasma generators
- Subject Areas: Railroads; Vehicles and Equipment;
- Accession Number: 00039206
- Record Type: Publication
- Source Agency: National Technical Information Service
- Report/Paper Numbers: Final Rpt
- Contract Numbers: DOT-FR-9-0009
- Files: TRIS
- Created Date: Nov 24 1976 12:00AM