UWSH CH 16 Flashcards
Are plugs authorized that are wrapped in fabric or rubber?
No, only bare plugs are authorized
DC plugs must be what?
Standard Stock or Equal
In Good condition; no Chips, gouges, cracks
Are mechanical plugs with aluminum components authorized?
No, due to galvanic corrosion they are not
The plug must have a seating pressure rating of at least how many times the static pressure head it will be sealing?
One and One Half
What must be stamped on the end plate of the permanent waterproof tag attached to the plug?
The size range of each plug
Can a mechanical plug sealing surface be trapered?
No, must remain untappered
The top plate or washer must have an outside diameter larger than the opening being secured.
What kind if plug is this?
Mechanical Expandable Plug
When installing a plug when can diver leave the dive station?
1 - Not until Double Valve protection is stablished
2 - Repairs are complete
3 - The ship CO or his designated representative grants their permission
On flat bottom hulls what can divers use to assist them in relocating a plug?
A C-Clamp installed on the bilge keel, this also will not interfere or obstruct traffic along side
The expansion of the plug, rather than a differential pressure secures the plug in place and from the seal.
What type of plug?
Mechanical Expansion Rubber Plug
The diver must always ensure that this kind of plug is completely seated an sealed before checking for leaks
DC Plugs sealed with Binsuke
How do divers inspect patches with no means of internal venting?
(Sea Chest & Piping Systems)
Visually inspect by divers for reduced gasket compression indicating loss of seal on the internal not to exceed every 7 days
When using J-Bolths to attach a patch to a sea chest grating or spreader bars, the patch should be ____ over the opening?
Centered
What determines the extent of a rigging plan?
The type and size of the patch to be installed
What must he rigging plan identify/include?
1 - lifting requirements
2 - securing and attachment requirements
3 - Manufacturer and weight testing requirements (lifting straps, wire)
What is required for the installation of a cofferdam?
Rigging Plan
How often must internal bents be inspected for signs of leakage by ships sounding and security detail?
For sea chest and piping with internal means of venting, location of the affected items shall be reported to the ships chief engineer per Appendix G
An interval not to exceed every seven days
After installation of a patch what must be confirmed at he internal repair area prior to complete removal of pipping connection fasteners?
Zero Leak Rate Seal
What is necessary to check after sealing a patch?
A final check of all support rigging and tightening of J-Bolts to verify integrity of patch
After dewatering is complete, eductors shall be secured. Eductors ___ ___ be left running to maintain a differential pressures seal
Shall Not
How are patches de-watered?
All patches shall be dewatered by draining the sea chest at an internal drain valve or piping connection or by use of an aductor installed directly on the patch
What is the primary method of securing a patch to the hull?
J-Bolt or hogging lines secured to permanent structures, sea chest grates, splitter bars or the main deck
When should a stand-off be used?
When the hull configuration limits the force applied to the hogging line
What is essential to achieve a positive seal when installing a patch?
Removal of all fouling and corrosion
