design review ul vibration test apparatus

Design ReviewUL Vibration Test Apparatus

May 13, 20131:30PM Est.

UL Vibration Test Apparatus 2

Project & Team InformationProject: UL Vibration Test ApparatusProject Number: 13471

Customer: Eaton Corporation (previously Cooper Crouse-Hinds Industries)Customer Contacts: Joe Manahan

Ed Leubner

RIT Faculty Guide: Dr. Benjamin Varela

Project Team: Walter BergstromSean CootsSpencer CrandellMark Ellison

February 21, 2013


Presentation Overview

1) Detailed Design Review Overview

Appendix: UL Test Stand and Project Background

February 21, 2013


Detailed Design Review

• Discussed Design: – Adjustment Mechanism– Crank Arm

• Key Action Items:– Adjustment Mechanism Strength– Crank Arm

• Actions Taken:– Crank Arm to be a single piece

February 21, 2013


Final Design

February 21, 2013


Variations from Design

February 21, 2013


Setup

February 21, 2013


Testing• Displacement testing completed on the system• As motor implementation is not within the scope of this

project, frequency was not validated• Test frame rigidly fastened to testing table

– Angle steel welded into frame shape– Aluminum cantilever with flange connection

• Dial indicators used in two locations to verify the displacement across the system– Contacting linear slider box– Contacting collar at connection to vertical conduit

February 21, 2013


Testing

February 21, 2013

Dial Indicator Contacting Slider Box Dial Indicator Contacting Conduit Collar


• Test 1: Verify zero-displacement– Centering dowels mated between adjustment

mechanism and rotating disk to signify zero-displacement

– Dial indicators showed zero displacement for the system

• Test 2: Verify 3 displacement values– 0.016”: found that dial indicators give very

low value for displacement (.004-0.008”)– 0.100”: again found that measured values

were lower than expected (0.045-0.055”)– 0.250”: met expected displacement value

within ± 0.010”

• Test 3: Verify torque– Torque wrench used not ideal; not precise

enough to measure low torque range– Did verify that the required torque to drive

the steady-state system is below ~2 lbf-ft

February 21, 2013

Cantilever

Flange Connection

Vertical Conduit

Conduit Collar

Testing Table

Test Frame


Testing Conclusions• Zero-displacement point is validated• Displacement measurements do not agree at low eccentric

values, but they do at higher distances– Postulated that the dial indicators are not precise enough to

accurately measure low eccentric distances

• Torque measurement has a high degree of uncertainty due to the low level of precision associated with the torque wrench used during testing

• Recommended:– Purchase more precise dial indicator (re-test)– Purchase more precise torque wrench (re-test)

February 21, 2013

Frame Design

February 21, 2013 UL Vibration Test Apparatus 12

44”34”

Frame Design


Advantages:• Allows for a single technician to mount the luminaire• Extra support of U-channel decrease vibration of system• Rubber pads in-between supporting beams help in

dampening the system• More space efficient than current design• *Approximately 44” X 34” footprint• Footprint may become larger due to resonate frequency

of design (to be tackled by next senior design group)

Motor Selection• 3-Phase, 240V AC Motor

• Steady-state period– No acceleration of system

• lbfft• This corresponds to a motor horsepower of 0.41,therefore a 1hp motor is desired

– Where r= in (stroke of crank), θ is angle of rotation of the motor (

• Start-up period

• Where:

• Assuming 50-60 seconds to reach 2000RPM, Treq3 lbfft



• At 2000RPM, a general purpose 1HP AC Baldor motor will produce 90ozft 5.7lbft torque• Our estimated range for required start-up torque is highlighted in yellow• At ~5.7lbft torque, it is estimated that 2000RPM will be reached in approximately 30

seconds• A variable-frequency drive will be used to obtain the required 2000RPM speed

Recommended Motor



Parameter Governing Equation Value Max Bearing Load

Upper bearing force 2450lbf 3150lbf

Lower bearing force 1225lbf 3150lbf

Se 1.10e4psi -

F.O.S. Shaft 10 -

F.O.S. Key 39 -

• Where ka, kb and kc are Marin factors for surface condition, size, and loading conditions, respectively.

• l1=2 , l2=4 , σmin, σmax, Sy, Sut can be found in Appendix

𝜎 𝑎=|𝜎𝑚𝑎𝑥−𝜎𝑚𝑖𝑛

2 | 𝜎 𝑚=𝜎𝑚𝑎𝑥+𝜎𝑚𝑖𝑛

2

Lubrication

• Drive Shaft Bearings: Double sealed flange mount bearings with easy access grease zerk fittings.

• Linear Bearings: Double sealed closed bearings with easy access grease zerk fittings.

• Crank Arm Bearings: Double Sealed roller bearings pre-packed with grease . Easy access for lubrication by taking off Polycarbonate cover.


Budget


Questions For Customer


Open Discussion

• Any questions?• Design concerns not discussed?


AppendixUL Test Standard and Project Background


Project Background• To pass safety requirements for certification the luminaires must meet a series of

Underwriters Laboratories Inc. Standards.• A Vibration Test Stand is currently being used by Cooper Crouse-Hinds to test

pendant mount luminaires according to section 33 of the UL844 Standard. • The Current Vibration Test Stand is outdated, has multiple design flaws, and design

documentation and drawings are non-existent.• Cooper Crouse-Hinds would like a new modernized Vibration Test Stand to be

developed that addresses some of the design flaws of the current system while maintaining UL844 Test Standards. This new Design must also have a LabView interface and control capability integrated into the system.

February 21, 2013


Design Goals over Winter/Spring MSDNote: It has been decided that this apparatus will be developed in multiple Senior Design Sequences.

• Provide customer with two design concepts for vibration mechanism• Develop a final design of the vibration mechanism.• Design a steel test frame that will support the vibration mechanism and

the vertical conduit.• Design but do not develop steel frame for entire vibration test machine.• Develop a full set of engineering drawings.• Calculate and select the required drive train system components.• Purchase materials, machine components, and assemble the vibration

mechanism and test frame.• Test the mechanism to ensure that it meets 1/32” deflection requirement

February 21, 2013


Summary of UL844 Vibration Test Standard

LUMINAIRES FOR USE IN HAZARDOUS (CLASSIFIED) LOCATIONS – UL 844Section 33 – Vibration Test Standards

• Luminaire is to be subjected to 35 hours of vibration testing.• Luminaire assembly is to be attached to a 26-1/2” long conduit via NPT threading.

The other end of the NPT threaded pipe is to be secured to the hub of a rigid mounting frame so that the conduit hangs vertically. The conduit should correspond to the smallest size of threaded conduit hub that is designed to attach to the Luminaire being tested.

• The horizontal force to be applied to the system in order to obtain the deflection must me located 4” above the location of the conduit where the Luminaire attaches.

• The deflection must be 1/32” with 1/16” total deflection per cycle.• The system must run at 2000 cycles/min.

February 21, 2013


UL844 Vibration Test Standard

February 21, 2013


Design Flaws Associated with Original Design

February 21, 2013

• Difficult for one technician to set up test• Lubricant not contained• Machine components exposed to contaminants• Belts used (slipping)• Uses single speed motor with a speed reducer• Frequency adjustment dial held in place with rope• No displacement adjustment • Attachment collar may experience minor buckling• Does not accounted for part wear and tolerance stack up

Customer Design Needs

Need # ImportanceHigh 3 – 2 – 1 Low

Design Criteria Measure of Effectiveness

CN1 3 Obtain vibration frequency of 2000 cycles/min Stroboscope

CN2 3 Create displacement of 1/32” at 22.5” bellow pipe flange Dial Gauge

CN3 2 Adjustment of attachment collar position for perpendicularity ___

CN4 2 240 V electrical input ___

CN5 2 System envelope size is maintained or decreased from original system

___

CN6 1 Mounts to current anchor points in floor ___

CN7 3 Capability to adjust for different pipe sizes ___

CN8 1 Use current flange mounting for pipes ___

CN9 2 Design in an easily removable collar ___

CN10 3 Will support multiple types of Luminaires ___

CN11 2 Easy to mount the Luminaires 1 Technician can run entire test

CN12 1 Ease of lubrication ___

CN13 2 Containment of Lubricant Look for leaking of Lubricant

CN14 3 System to not run near resonate frequency Does not shake itself apart

CN15 1 Minimize noise of system Under 85 decibels(OCIA standard for requiring

ear protection)


PUGH Matrix: Rotational to Linear Motion Mechanism


# Evaluation Criteria Crankshaft Eccentric Shaft Scotch Yoke Cam & Follower1 Robustness s + + -2 Cost + - + s3 Design Simplicity s + s s4 Adjustability s - + s5 Component Wear s s - -6 Ease of Lubrication - + - -7 Part Replacement s - + +8 Accuracy/Tolerance Stack-up + + + -9 Ease of Maintenance s s + s10 Ease of Manufacture + - + s11 In-house Manufacture + - + s12 Ease of Assembly s s s s13 Noise/Vibration + + - s14 Safety s + s s

4 1 5 -3

Rotational to Linear Conversion

Sum

PUGH Matrix: Slider Mechanism


# Evaluation Criteria Pillow Block Bearings Viscous Fluid Layer Roller Bearings w/wheels Linear Bearings on rails1 Robustness + + S +2 Cost S + S S3 Design Simplicity S S - S4 Component Wear + - S +5 Ease of Lubrication + + S +6 Containment of Lubricant S - S +7 Part Replacement + - + +8 Ease of Maintenance + S + +9 Ease of Manufacture + + S +

10 In-house Manufacture S S S S11 Ease of Assembly S S S S12 Noise/Vibration S - S S

6 0 1 7

Slider Mechanism

Sum

PUGH Matrix: Displacement Adjustment Mechanism


# Evaluation Criteria Screw Linear Actuator Pivot Cam slider w/ tightening bolt1 Robustness - + -2 Cost - + +3 Design Simplicity - + +4 Part Replacement - + S5 Accuracy of Adjustment + - -6 Ease of Manufacture - S +7 In-house Manufacture - + +8 Ease of Assembly - + +9 User Friendly + S S

-5 5 3

Displacement Adjustment Mechanism

Sum


Risk Assessment

design review ul vibration test apparatus

Documents

ul vibration test apparatus12

ul test stand

low value

displacement values0

low torque rangedid

expected displacement

low eccentric values

low level of precision