Furuno CH-300 Installation Manual page 64

APPENDIX 2 HOW TO INSTALL THE RETRACTION TANK FOR WOODEN VESSEL
Selection of the flow rectification component
According to the vertical distance between the bottom line of the keel and center of the retraction
tank, select a fairing or stainless plate as the flow rectification.
Keel
Recommended dimensions for the stainless plate
• Length (bow-stern direction): R. P + 20 mm or more
• Length (both sides direction): Pipe O.D + 100 mm or more
• Thickness (T): 10 mm or more
• Diameter of the hole: Pipe I.D + 1 mm
Note: For flat bottom hull, prepare a wooden reinforcement block to decrease the vibration of the
retraction tank. The recommended dimensions of the reinforcement block are shown below.
Recommended dimensions for the reinforcement block
• Height: 300 mm or more
• Length (bow-stern direction): Same as the distance between the ribs
• Length (both sides direction): Pipe O.D + 100 mm or more
• Diameter of the hole: Pipe O.D + 1 mm
Reinforcement block
Keel
Rib
Stainless
plate
AP-8
Retraction tank
≤ 1000
≥ Pipe O.D + 100
≥ Pipe O.D + 100
A < 50 mm: Select a stainless plate
A ≥ 50 mm: Select a wooden fairing
R.P: Rib pitch
Pipe I.D: Inside diameter of the PVC pipe
Pipe O.D: Outside diameter of the PVC pipe
Rib
T ≥ 10 Rib