MAST CLIMBING ACCESS SYSTEMS
CASE STUDY:
NATURAL DRAFT COOLING TOWERS RESTORATION
T H I S
D O C U M E N T
C O N T A I N S
P R O P R I E T A R Y
A N D
C O N F I D E N T I A L
I N F O R M A T I O N .
D U P L I C A T I O N ,
R E P R O D U C T I O N
O R
U S E
O F
T H I S
D O C U M E N T
O R
I T S
C O N T E N T
I N
A N Y
F O R M
O T H E R
T H A N
A S
E X P R E S S L Y
P E R M I T T E D
B Y
F R A C O
P R O D U C T S
L T D
I S
P R O H I B I T E D
SPECIFICATIONS OF THE COOLING TOWER
• Part of a coal-fired steam-electric power station
• Type: Natural draft (hyperbolic)
• Height: 139.6m (458’)
• Min. diameter: 55.8m (183‘)
• Max. diameter: 103.3m (339‘)
• Inclinations: from 17o to -3o
CONTRACTOR TASKS
• Concrete repair
• Rebar replacement
• Cathodic protection
• Do not interrupt operation of the power station
FRACO’S CHALLENGES
• Access a hyperbolic structure
• Auto-level deck at all positions from 17o to -3o
• Electric unit
• Base installed in cofferdam and 1.2m (4’) of salty water
• Tie-ins without damage to existing rebar
• Material hoist 567 kg (1,250 lbs) capacity
• 6 x 110V x 15 amp
INITIAL ANALYSIS
PLATFORMS LAYOUT – GROUND LEVEL
PLATFORMS LAYOUT – LEVEL 63
PLATFORMS LAYOUT – TOP LEVEL
PLATFORM AUTOLEVELLING PRINCIPLE
ADJUSTABLE ANCHORING DEVICE
ADJUSTABLE BASE