System and method for modification of a baseline ballast arrangement of a locomotive

A system for modification of a baseline ballast arrangement of a rail vehicle having an overall tractive effort rating based on symmetrical distribution of weight and driving torque applied by the rail vehicle to axles of the rail vehicle, the system comprising:

• a rail vehicle truck comprising a first axle, a second axle, and a third axle, the first axle of the truck uncoupled from a traction system of the rail vehicle, and the second axle and the third axle of the truck coupled to the traction system of the rail vehicle;
• a first suspension assembly comprising a first spring and coupling the first axle to the truck, the first suspension assembly having respective mechanical characteristics to apply a first portion of a rail vehicle weight to the first axle;
• a second suspension assembly comprising a second spring and coupling the second axle to the truck, the second suspension assembly configured to apply a second portion of the rail vehicle weight to the second axle;
• a third axle of the rail vehicle truck coupled to the traction system of the rail vehicle, wherein the first axle, the second axle, and the third axle comprise axles having substantially equal weight-carrying capability;
• and
• a third suspension assembly comprising a third spring and coupling the third axle to the truck, the third suspension assembly configured to apply a third portion of the rail vehicle weight to the third axle, the first spring, the second spring, and the third spring having at least one of different spring constants or different spring geometries, wherein the second suspension assembly and the third suspension assembly have respective mechanical characteristics different than the mechanical characteristics of the first suspension assembly so that the second portion of the rail vehicle weight and the third portion of the rail vehicle weight applied to the respective second axle and third axle are different from the first portion of the rail vehicle weight applied to the first axle,
• wherein the rail vehicle weight is asymmetrically distributed to the first axle, the second axle, and the third axle,
• wherein the asymmetrical distribution of the rail vehicle weight is configured to allocate more weight to the second axle and the third axle to transmit corresponding incremental amounts of tractive effort for a given amount of a driving torque applied to the second axle and the third axle via the traction system of the rail vehicle, and
• further wherein an amount of the rail vehicle weight that is allocated from the first axle to the second axle and the third axle allows for modification of a baseline ballast arrangement by reducing an amount of ballast in the baseline ballast arrangement corresponding to the amount of the rail vehicle weight that is allocated from the first axle to the second axle and the third axle.

A method for modification of a baseline ballast arrangement of a rail vehicle having an overall tractive effort rating based on symmetrical distribution of weight and driving torque applied by the rail vehicle to axles of the rail vehicle, the method comprising:

• providing a rail vehicle truck comprising a first axle and a second axle, the first axle of the truck uncoupled from a traction system of the rail vehicle, the second axle of the truck coupled to the traction system of the rail vehicle;
• coupling the first axle to the truck with a first suspension assembly having a first spring;
• configuring the first suspension assembly with mechanical characteristics to apply a first portion of a rail vehicle weight to the first axle;
• coupling the second axle to the truck with a second suspension assembly having a second spring, the first and second springs having at least one of different spring constants or different spring geometries;
• choosing the first axle and the second axle to have substantially equal weight-carrying capabilities;
• configuring the second suspension assembly with mechanical characteristics that are different from the mechanical characteristics of the first suspension assembly to apply a second portion of the rail vehicle weight to the second axle that is different from the first portion of the rail vehicle weight that is applied to the first axle such that the rail vehicle weight is asymmetrically distributed among the first axle and the second axle, wherein the asymmetrical distribution of the rail vehicle weight is configured to allocate more weight to the second axle to transmit a corresponding incremental amount of tractive effort for a given amount of a driving torque applied to the second axle via the traction system of the rail vehicle;
• and
• modifying a baseline ballast arrangement of the rail vehicle by reducing an amount of ballast in the baseline ballast arrangement corresponding to an amount of weight that allocated from the first axle to the second axle.

A system comprising:

• a first rail vehicle truck comprising an unpowered axle that is decoupled from a traction system and a first powered axle that is coupled with the traction system;
• a first suspension assembly coupling the unpowered axle to the first rail vehicle truck, the first suspension assembly including a first spring to apply a first portion of rail vehicle weight to the unpowered axle;
• and
• a second suspension assembly coupling the first powered axle to the first rail vehicle truck, the second suspension assembly including a second spring to apply a second portion of the rail vehicle weight to the first powered axle, the first and second springs of the respective first and second suspension assemblies having at least one of different spring constants or different spring geometries such that the second portion of the rail vehicle weight that is applied to the first powered axle is greater than the first portion of the rail vehicle weight that is applied to the unpowered axle in order to provide an asymmetrical distribution of the rail vehicle weight.