Development Of Design Equations For A Square-tube Subbase Supporting A Shaft-mounted Speed Reducer

Shaft mounted speed reducers are used in material handling applications, such as conveyor systems for transporting ore out of mine shafts. A subbase joins the reducer with an electric motor, and serves to limit the misalignment between the motor shaft and the reducer input shaft. The entire assembly is supported at two points: the axis of rotation of the reducer output shaft, which is fixed, and a clevis-pin joint under the motor, which prevents rotation of the assembly about the reducer output shaft axis. In an effort to reduce the production and material costs of subbases that support shaft mounted reducers, Rexnord Corp. is implementing subbase designs that are lighter weight and easier to manufacture than current designs. Impeding the implementation of lower cost designs is the lack of an equation to properly choose subbase dimensions for acceptable values of shaft misalignment. Trial and error in subbase construction may provide designs that give acceptable results for misalignment. Given an equation, however, the weight could be minimized while still limiting misalignment at the coupling location. The project goal is to provide equations that give shaft misalignment as a function of three subbase parameters: tube thickness, mounting strap width, and end cap thickness. Developing design equations by analytical methods is investigated first. Next, finite element models are used to check the analytical results for accuracy. Finally, finite element models are used to perform design sensitivity studies where needed. The final equations for misalignment are given as functions of the three design variables.

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 Tech

Year dc:date.issued

2002

Author dc:creator

• Brown, William E. III

Chair dc:contributor.committeechair

• Mitchiner, Reginald G.

Committee members dc:contributor.committeemember

• Inman, Daniel J.
• West, Robert L. Jr.

• FEA
• DOE
• Square Tube
• Motor
• Subbase
• Speed Reducer

Statement dc:rights

• In Copyright

Licence dc:rights.uri

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

Dc Identifier Other

etd-01182002-104559

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/30983