HPSW

Question 1

What is the HPSW operating pressure

Answer 1

7 bar

Question 2

What is fitted to prevent over pressurisation

Answer 2

10% leak off valve or pressure relief valve

Question 3

State 6 uses of HPSW

Answer 3

Fire fighting
Making fresh water
Flushing heads
Pre wett
Emergency cooling to main propulsion
Auxiliary machinery cooling water system

Question 4

Explain the flow of SW from the sea to the ring main

Answer 4

Each pump takes its suction from the sea through strainers and then gets discharged to the ring main via the riser

Question 5

Explain the HPSW ring main

Answer 5

A ring of pipe work running around 2 deck that can be sub divided by the use of isolation valves

Question 6

How are the pumps driven and where can they be operated from

Answer 6

Electrically driven and can be operated remotely or locally

Question 7

Where will the HPSW sprays be located

Answer 7

Magazines
Funnels
Galley
Paint locker
Inflame stores

Question 8

Explain the pre wett system

Answer 8

Operated in an NBC environment where to reduce nuclear biological and chemical contamination levels on the upper deck

Question 9

Explain DC state 1

Answer 9

All the pumps are running and the dc state 1 valves are shut and the HPSWM is isolated into zones

Question 10

Explain DC state 3

Answer 10

One pump is running but other pumps are on standby and can be started if pressure drops and all DC valves are open

Question 11

When may more pumps be introduced

Answer 11

If the pressure drops