Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Structural Analysis of a Nuclear Fuel
Handling Machine Overview
By: Steve Sherfey, Westinghouse Electric Company LLC
1

Westinghouse Non-Proprietary Class 3
Agenda
© 2012 Westinghouse Electric Company LLC. All Rights Reserved.
•
Abstract
•
Analytical Model
•
Hoist & Hook Model Configurations
•
Acceptance Criteria and Codes
•
Service Condition
•
Seismic Condition
•
Special Modeling Technique
•
Primary and Secondary Evaluations
2

Westinghouse Non-Proprietary Class 3
Abstract
© 2012 Westinghouse Electric Company LLC. All Rights Reserved.
•
Nuclear Power Plants contain Fuel Handling Machines
(FHMs) for moving fuel
•
Rail Mounted, Motorized, and Computer controlled
•
Very top heavy
•
Very difficult to qualify
•
Engineers must use a special modeling technique for qualification
3

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model
Main Hoist
Upper Bridge
Lower Bridge
SFP Hoist
Upper Rail
Lower Rail & Wheel
Power Center
Lower Rail & Wheel
Motor
4

Westinghouse Non-Proprietary Class 3
.
© 2012 Westinghouse Electric Company LLC. All Rights Reserved.
5

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model - Inputs
•
Design Drawings
•
Boundary Conditions
•
Material and Sectional Properties of Structural Components
•
Proper member releases at bolted connections
•
Response Spectra for the SSE Event
•
Create analytical model using Structural Analysis Computer
Code such as GTStrudl
6

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model – Material Properties
7

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model – Sectional Properties
8

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model
Response Spectrum (X Direction)
9

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model
Response Spectrum (Y Direction)
10

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model
Response Spectrum (Z Direction)
11

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Analytical Model
12

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Hoist & Hook Model Configurations
Main Hoist at Mid Span,
SFP Hoist at North End.
Main Hoist at North End,
SFP Hoist at South End.
Main Hoist at North End,
SFP Hoist at Mid Span.
N
13

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Acceptance Criteria and Codes
•
Plant Design Specification & Response Spectra
•
AISC Manual of Steel Construction, Allowable Stress
Design
•
ASME NOG-1, Rules for Construction of Overhead and
Gantry Cranes
•
ASME B&PVC Code, Section III, Division 1, Sub-Section
NF
•
CMAA-70, Crane Manufacturers Association of America,
“Specifications for Top Running Bridge & Gantry Type
Multiple Girder Electric Overhead Traveling Cranes”
14

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Service Condition
•
Analyzed for all service loads without seismic excitation and qualified per CMAA-70
•
Loadings shall include Inertia of mass loads from movement of Crane, Trolley, Hoist, and Lifted Load
•
Loadings due to Wind, Skewing, Collision, Platform, and maximum critical hook loads shall be considered when applicable.
15

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Seismic Condition
•
Analyzed for all normal operation deadweight loads acting simultaneously with seismic excitation from Safe Shutdown
Earthquake (SSE)
•
Response spectrum method shall be used
– Proper Combination of modes of seismic vibration
– Proper Combination of directional seismic responses
– Proper Damping factors
16

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Special Modeling Technique
•
Sliding or rolling must be considered to prevent overturning
•
Force required to cause sliding or rolling must be calculated
•
Each crane drive wheel is restrained in the movement direction with a specified spring stiffness
•
The spring stiffness is derived by iteration
•
An initial stiffness is assumed; the value is changed & analysis rerun until the wheel seismic load equals the sliding/rolling force.
17

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Required Crane Evaluations
Primary Evaluations:
Wheel Reactions, Displacements, Accelerations, Structural
Steel Stresses, Plate Element Stresses
Secondary Evaluations:
Welds, Beam Connection Plates, Beam Flange/Web
Deformations, Stiffener Plates, Bolts, and Wire Ropes
18

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Some Typical Items Being Evaluated
TUBE ON TUBE
CONNECTION
M SHAPE TO W SHAPE
CONNECTION
THE END
19

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Bolt Evaluations
•
The maximum forces and moments for each connection type can be extracted from GTStrudl
•
30-40 types of major bolted connections in the FHM
•
Can be grouped in 10-15 typical connection types
•
Each connection type has a different bolted configuration pattern due to size, number, and spacing of bolts
•
Each configuration has different sectional properties required for calculating max shear and tension stresses
•
Bolts must be qualified to applicable code
20

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Slack Rope Evaluations
•
If the lifted load has an upward seismic acceleration greater than 1 g, the hoist wire rope may need to be evaluated for the slack rope condition
•
ASME NOG-1 provides design guidance for performing this evaluation
•
The maximum slack rope allowable is based on a percentage of the rope breaking strength
•
A non-linear time history analysis is normally required for performing the slack rope analysis
•
The analysis is only used for evaluating the rope for the most probable lifted load condition
21

Westinghouse Non-Proprietary Class 3 © 2012 Westinghouse Electric Company LLC. All Rights Reserved.
Structural Analysis of a Nuclear Fuel Handling Machine
THE END
22