systems level design review ul vibration test apparatus
DESCRIPTION
Systems Level Design Review UL Vibration Test Apparatus. January 11, 2013 KGCOE Room # 2255 10:00AM-12:00PM Est. Project & Team Information. Project: UL Vibration Test Apparatus Project Number: 13471 Customer: Eaton Corporation (previously Cooper Crouse-Hinds Industries) - PowerPoint PPT PresentationTRANSCRIPT
Systems Level Design ReviewUL Vibration Test Apparatus
January 11, 2013KGCOE Room # 2255
10:00AM-12:00PM Est.
UL Vibration Test Apparatus 2
Project & Team InformationProject: UL Vibration Test ApparatusProject Number: 13471
Customer: Eaton Corporation (previously Cooper Crouse-Hinds Industries)Customer Contact: Joe Manahan
RIT Faculty Guide: Dr. Benjamin Varela
Project Team: Walter BergstromSean CootsSpencer CrandellMark Ellison
January 11, 2013
UL Vibration Test Apparatus 3
Project Background• Cooper Crouse-Hinds develops luminaires that are used in hazardous
environments where ignition or explosion can have catastrophic consequences.• 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 • The Current Vibration Test Stand is outdated, has multiple design flaws, and design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.
January 11, 2013
UL Vibration Test Apparatus 4
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– One of the two designs must be an eccentric shaft mechanism while the customer is open to
considering other design alternatives.– After discussing benefits and costs of the designs in this Systems Level Design Review, the Customer
will decide on the vibration mechanism to be developed further.
• 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
January 11, 2013
UL Vibration Test Apparatus 5
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.
January 11, 2013
Force Applied to Deflect Luminaire
Equations of relative motion were applied to derive the acceleration of the desired deflection assuming a constant angular velocity of the primary shaft. The moment of inertia was than approximated for the conduit with 100lbf cylinder at its end. Assuming the system acted as a pendulum and using the moment of inertia and acceleration we acquired a force. This was then superimposed with the force needed to bend the conduit (cantilever pipe) to the proper deflection.
The calculated force was approximately 400lbf.
January 11, 2013 UL Vibration Test Apparatus 6
UL Vibration Test Apparatus 7
UL844 Vibration Test Standard
January 11, 2013
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Design Flaws Associated with Current Design
January 11, 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 NeedsNeed # Importance
High 3 – 2 – 1 LowDesign 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)
Rotational Input at 2000 rpm
Rotational to Linear Motion Mechanism
Options:
• Eccentric Shaft• Crankshaft Variation for
Adjustment Capabilities• Scotch Yoke
• Variation for Adjustment Capabilities?
• Cam Follower
Output Linear Motion to Slider
Mechanism
• Allows for design of a single motor input and slider output mechanism for either the eccentric shaft or scotch yoke design
• Slight adjustments to frame required for each case due to the orientation of the motor (either horizontal or vertical)
January 11, 2013 UL Vibration Test Apparatus 10
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Continued (next slide)
Functional Decomposition (Page 1 of 2)
January 11, 2013 UL Vibration Test Apparatus 12
Functional Decomposition (Page 2 of 2)
Slider Mechanism
Linear bearing with rails
Roller bearings w/ wheels
Full fluid boundary w/ lubricant
Magnetic
Pillow block bearings Notes:
• Ranked from top to bottom, best to worst
• Need to ask exactly what mechanism the current design employs
• Issue is lubrication and lubrication containment if bearings are not used
January 11, 2013 UL Vibration Test Apparatus 13
Rotational to Linear
Mechanism
Scotch Yoke
Crankshaft
Cam Follower
Screw Actuator
Eccentric Shaft Notes:
• Ranked from top to bottom, best to worst
• Also a linear motor option that does not fall under this category but still converts electrical energy to mechanical
January 11, 2013 UL Vibration Test Apparatus 14
PUGH Matrix: Rotational to Linear Motion Mechanism
January 11, 2013 UL Vibration Test Apparatus 15
# 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
Ecce
ntric
Sha
ftEccentric Shaft
(Custom Purchase)
Shaft Bearing(s)(Purchase)
Connecting Rod(Custom)
Connecting Rod Bearing(Purchase)
Shims(Purchase)
**Note: Green boxes denote optional design components
Notes:
• Current design in use at Cooper
• Simple design• No adjustment
capability• Eccentric shafts
expensive to purchase• Relatively few moving
parts• Lubrication of
connecting rod must be further studied
Option 1
January 11, 2013 UL Vibration Test Apparatus 16
January 11, 2013
Scot
ch Y
oke
Rotary Disc(Custom)
Shaft(Purchase)
Yoke Plate(Custom)
Pin(Purchase)
Connection to Slider Mechanism
(Custom)
**Note: Green boxes denote optional design components
Notes:
• Alternate design• Fairly simple• Adjustment capability• Lubrication of system
must be further studied
Gear (Purchase)
Key (Purchase)
Option 2
May be directly built into design
Scotch Yoke CAD Concept
January 11, 2013 UL Vibration Test Apparatus 18
PUGH Matrix: Slider Mechanism
January 11, 2013 UL Vibration Test Apparatus 19
# 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
January 11, 2013 UL Vibration Test Apparatus 20
# 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
Cost Analysis
January 11, 2013 UL Vibration Test Apparatus 21
Component Count Approximate Cost Per ItemScotch Yoke Yoke 1 $20 Drive Shaft 1 $120 Rotating Plate 1 $100 Pin 1 $20 Bushing 1 $40
Stroke Adjustment Mechanism 1 $40 Eccentric Shaft Eccentric Shaft 1 $500 Pivot Arm 1 $100 Shaft Bearings 2 $40 Pivot Arm Bearing 1 $20 Guide Rail System Bearing 1 $20 Frame Base plate 12" wide x 3/4" thickness x 48" long 1 $230 Channel Plate 12" wide x .380 thickness x 72" long 1 $250 Steel Angle 6 $200 Fasteners and Associated $200 Guide Rail System Linear Pillow Block Bearings 4 $320 Hardened Ground Shaft 2 $120 Shaft Base Mounts 4 $100 Assorted 2" NPT Pipe 26.5" length 1 $30 Dial Indicator 1 $30 Pipe Flange 1 $40 Approximate Cost w/ Scotch Yoke $2,100 Approximate Cost w/ Eccentric Shaft $2,500
January 11, 2013 UL Vibration Test Apparatus 22
Risk Assessment
January 11, 2013 UL Vibration Test Apparatus 23
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Continued (next slide)
Project Schedule (Page 1 of 2)
January 11, 2013 UL Vibration Test Apparatus 25
Project Schedule (Page 2 of 2)
Suggested Design Implementation
• Scotch Yoke Design• Linear Bearings on Rails• Pivot Cam for Eccentric Adjustment
Mechanism• AC Motor with Adjustment• Redesigned Flange Platform
January 11, 2013 UL Vibration Test Apparatus 26
Open Discussion
• Any questions?• Design concerns not discussed?• Feed back on work done to this point?• Feed back on method for calculating
deflection force?• Follow-up meeting needed?
• Customer decision on Vibration MechanismJanuary 11, 2013 UL Vibration Test Apparatus 27