Glad Hand

Condemning Criteria Development for Gladhand Locomotive Hose AssembliesCharles FerrieraLukasz KurczabEvan McCunePaul SnyderYan WuFaculty Advisor: Dr. Norbert Mller

Professional AdvisorsJames Howell, Union PacificBill Sheesley, Union Pacific

Sponsor BackgroundUnion Pacific was established in 1862 Headquartered in Omaha, NebraskaTotal employees as of 2010: 42,884USAs largest railroad network consisting of 31,900 miles They ship a wide variety of cargo including automobiles, food, and coal

Problem StatementUnion Pacific has expressed difficulty with gladhand air hose assemblies separating during train operation.Unintentional separation causes the emergency brakes to be applied, causing significant delay.The company would like our design team to investigate solutions to decrease the frequency of these separations.

Due to the age of the rail industry and operating life of its components, the gladhand design was to remain unchanged.Development of a more stringent condemning criterion was proposed.If gladhand hoses that are likely to fail are detected before failure, they can be switched and decrease failure rate.

Problem Statement

Design SolutionDetermine force required to separate connectionLower pull-apart force = greater likelihood of failureTensile Testing:Documentation and Gauging:Gladhand age, type, gasket type, and go/no-go of AAR gaugesCorrelate force data to parameters documented

Rig DesignBasic ConceptWinch draws in tensionHose assembly fails at some unknown forceLoad cell transfers force data to a Data Acquisition System to be recorded

Frame Design2x2 Square Tube Steel (12 gauge)Bending calculations performed to ensure stability and safetyFactor of Safety = 9.4 under 1000lbs

BACD

Completed Testing Rig

Rig Testing

Progression of Testing: Initially sampled random hose combinationsThen, high and low force hose combinations and step inputsFinally, performance fatigue test under 50 trials

High Speed Video Capture

Gauge Construction

Results

Results

Results

Conclusions

Year of manufacture had an inconclusive effect on pull-apart force Hose assemblies are limited by the weaker of the two gladhand hosesGasket and gladhand type mismatches along with gauge No. 26320 failures cause gasket misalignments, therefore decreasing pull-apart forceRapid fatigue testing showed a steady decrease in separation force upon multiple couplings and decouplings

Recommendations

Implement gladhand quality inspection programDocument installation/removal datesPhysical deformation inspectionAAR specification testingInstall double wide gaskets on all gladhand hosesAvoid gladhand type mismatches, i.e. straight-15 degreeGasket reliability testingGuard arm crevice and bead documentation and testing

Questions?