HP & LP Air

Question 1

Why is HP air used on board?

Answer 1

Easily distributed throughout the ship.
Easily stored.
Flexibility and reliability of use.
Low risk of fire.

Question 2

Where is HP air used on board?

Answer 2

HPSWP Ringmain

Question 3

6 services that use HP air?

Answer 3

Diesel generator starting.
Gas Turbine starting.
Ship siren.
Breathing apparatus.
Weapon system operations.
Hydraulic system accumulator charging.
Air driven machinery.
Cross connection to low pressure air system.

Question 4

What is HP air operating pressure?

Answer 4

276 Bar.

Question 5

When will relief valves operate?

Answer 5

In order to relieve pressure, avoiding damage to HPAC and Ringmain.

Question 6

4 pressures of HPAC?

Answer 6

Stage 1: 4 Bar.
Stage 2: 17.5 Bar.
Stage 3: 68 Bar.
Stage 4: 276 Bar.

Question 7

Purpose of HPAC drain and separators and frequency of operation?

Answer 7

Blow oil and moisture to bilge, and separators force water droplets out the air.
Every 30 minutes.

Question 8

What pressure with the water jacket safety valve operate at and what system is it protecting?

Answer 8

3.5 Bar.

Question 9

LP operating pressure?

Answer 9

Up to 8 Bar.

Question 10

Four services that use LP air?

Answer 10

Pneumatic tools.
Radar wave guides.
Emergency Stern seal inflation.
Pneumatic surveillance panels.

Question 11

PPE when charging air bottles?

Answer 11

Goggles & Ear Defenders.