RNLI Atlantic 85, Manual

Page: 115 / 122

Activity 11 - Unplanned Maintenance
115
B Class Atlantic 85 Manual – First Issue, June 2017
Activity 11 - Unplanned Maintenance
Buoyancy tubes
Design and function
The sponson is divided into ten separate airtight
compartments to provide continuous buoyancy in the
event of damage being incurred. Each compartment
contains a cone that when pressurised faces aft but
should a section become damaged the pressure in the
adjacent section will force the cone back on itself to fill
the punctured area.
For this safety system to work it is essential that the
compartments are inflated from the bow, working aft.
The normal working pressure of all compartments in the
sponson is 1.5 pounds per square inch (psi). Although
pressures between 0.75 and 2.0 psi are acceptable.
The entire buoyancy tube should be periodically examined
for undue wear or leaks and the pressure of each
compartment checked. Wear will reduce the thickness of
the Hypalon coating and pressure will be lost.
Leaks can be found by applying soapy water to the
suspected areas.
cone-shaped
bulkhead
In the event of a leak, pressure will cause the cone-
shaped bulkhead in the adjoining compartment to invert,
effectively filling most of the damaged compartment
Tube repairs
Most small punctures can be repaired with a patch. The
procedure for gluing should be carried out in accordance
to the training given.
Relevant COSHH and risk assessments must be read prior
to any work being carried out. These assessments will cover
dangers to your health and others as well as ventilation
and Personal Protective Equipment (PPE) considerations.
The repair must be carried out in a well ventilated area
and also be allowed to cure in a warm, dry environment
otherwise the materials will not bond fully.
Stores required:
• Bostik 2402 two part adhesive (part number: 7-74)
• Bostik M-501 solvent (part number: 7-129)
• seam roller (part number: 7-1979)
• sandpaper (grade 80)
• chinagraph pencil
• crepe rubber
• rags
• hot air gun
• scraper
• pincers and scissors.