A finite element analysis and redesign of the draftsill casting on a railroad hopper car

This paper presents a static three-dimensional finite element analysis and redesign of a railroad hopper car draftsill. The purpose of the work was to modify the current draftsill structure to minimize its weight without compromising its current capabilities and foundry production specifications. The intuitive optimization procedure used both linear and parabolic isoparametric solid finite element models to check for solution convergence. In order to intuitively optimize the models, a composite plotting program was developed to display only the highest stresses at each node from all loading cases. This allowed for an overall visualization of low stressed regions for potential weight reduction. An additional study investigated the possibility of tapering the front and rear draftlugs for a better stress distribution in the draftsill's structure under loading. It was determined that a tapered relief of 0.025 - 0.050 in.(0.0635 - 0.127 cm) from the center of the draftlug to its outer edge would more effectively distribute the stresses created, and also reduce the maximum stress levels generated by at least 20 percent. All loading and geometry specifications used in this research were based on data provided by the Norfolk Southern Corporation. If both the redesign and tapered relief are adopted, then the final redesign will produce a draftsill that is approximately 106 lb(471.5 N) or 9.6 percent lighter than its original weight with maximum stresses reduced by 20 percent.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Mechanical Engineering

Department dc:contributor.department

Mechanical Engineering

Grantor dc:publisher

Virginia Polytechnic Institute and State University

Year dc:date.issued

1987

Author dc:creator

• Roach, Douglas Kevin

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/10919/71230

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/71230