Locomotive friction load
The locomotive frictional load (also frictional load , friction weight or adhesion weight ) denotes the portion of the mass of a locomotive that rests on driven axles . The pulling force of a locomotive is largely determined by the frictional load, since friction in mechanics is a prerequisite for power transmission during sliding or rolling movements .
definition
The mass of a locomotive is distributed over the driving axles as far as the permissible axle load of the routes to be traveled allows. Their axle load is therefore ideally just below the limit permitted by the route. In locomotives in which all axles are driven, the frictional load is identical to the locomotive service load ; in locomotives with non-powered running axles , especially in most of the larger steam locomotives , however, it is in some cases significantly lower.
At the US Chesapeake & Ohio Railway this was particularly high, so that the machines of the class H-8 with only six driving axles could achieve 230.4 tons of locomotive friction load. Its maximum axle pressure was 39.3 tons - a world record for steam locomotives .
On some steam locomotives of the Deutsche Reichsbahn ( DR series 06 , DR series 41 and DR series 45 ) the driving axle load could be set to 18 t or 20 t by means of adjustable compensating levers ; in the latter case, the load on the running axles was correspondingly lower. This enabled optimal tractive effort on both main and secondary routes with lower permissible axle loads.
The electric bogie locomotives , which have become the standard since the 1950s , have no running axles. Thus their friction weight corresponds to the total weight.
Individual evidence
- ^ Hans-Peter Bärtschi: Electric locomotives from Swiss factories. In: Verkehrshaus der Schweiz (Ed.): Coal, electricity and rails: The railroad conquers Switzerland. Verlag NZZ, Zurich 1998, ISBN 3-85823-715-9 , p. 284