Pumps And Primers

Question 1

What is priming?

Answer 1

The removing of air in the pump and replacing it with wate

Question 2

What can’t a centrifugal pump do that a positive displacement pump can?

Answer 2

Pump gasses

Question 3

Why must we flush all hydrants?

Answer 3

To prevent stones and debris damaging and effecting the impeller/ pump efficiency

Question 4

What is the snail shell shaped part?

Answer 4

Volute

Question 5

Give an example of a 3 stage centrifugal pump?

Answer 5

The Hp hose reel pump on the MAN

Question 6

What is the pro and con for centrifugal pumps?

Answer 6

Pro-the move a lot of water and are simple.

Con- can’t supply enough pressure for hosereels

Question 7

Name 4 types of pump?

Answer 7

Centrifugal,peripheral, ejector, positive displacement

Question 8

Another name for peripheral pump?

Answer 8

Regenerative

Question 9

What is the advantage of peripheral/regenerative pumps?

Answer 9

It allows water to be delivered at both high and low pressures simultaneously

Question 10

Required pump speed for hose reels?

Answer 10

3000rpm

Question 11

What is an ejector pump?

Answer 11

Used to pump water and gases with an existing flow of water

Question 12

When are submersible type ejector pumps commonly used?

Answer 12

Out of water from depths greater then the maximum practical suction lift

Question 13

What is the principle of operation of an ejector pump known as?

Answer 13

The Venturi principle

Question 14

What is the word used to describe surrounding water to join the propellants stream?(ejector pumps)

Answer 14

Entrained

Question 15

What type of pump is the stirrup pump?

Answer 15

Positive displacement

Question 16

Name two types of PD pumps?

Answer 16

Stirrup, peristaltic

Question 17

How are the LPPs primed?

Answer 17

Using an exhaust gas ejector

Question 18

How much air/ water can a reciprocating primer discharge every revolution?

Answer 18

1L

Question 19

How do you know when a reciprocating primer as got rid of all the air?

Answer 19

A popping sound before the cam is disengaged

Question 20

How do you know when the exhaust gas ejector primer has got rid of all air?

Answer 20

When clouds of steam issue from the exhaust

Question 21

What is a pumps nominal output/duty point?

Answer 21

The pressure at which the pump is most effective. E.G:2250L/min at 7 bar

Question 22

What is the maximum water relay pressure?

Answer 22

10 bar

Question 23

Why should the 1st booster pump be closer to the base pump?

Answer 23

To compensate for the reduced output after suction.(reduced by 2 lengths)

Question 24

Why should the incident ground pump be independent?

Answer 24

Branch ops won’t be effected by fluctuations in relay

Pump has a water reserve

Question 25

Before charging the hose,Why should a spare delivery be left open when part of a relay?

Answer 25

To release air, to save releasing all air from all pumps at the fireground pump

Question 26

What pressures should relay pumps be working at?

Answer 26

7 bars

Question 27

How could you cool the LPP if used as the fireground pump?

Answer 27

Attach a dividing breech and trickle away some water

Question 28

What is Water carrying/shuttling?

Answer 28

When distance between water source and fireground is very big. But dose not warrant a relay

Question 29

What are 3 methods of water shuttling/carrying?

Answer 29

Appliances, flexitainrs,water carrier

Question 30

What can a flexitainer hold?

Answer 30

5000L

Question 31

What does the water carrier hold?

Answer 31

10000L

Question 32

Steps for priming the LPP?

Answer 32

• Open manual priming valve
• start engine
• full throttle
• pull up priming lever
• when delivery gauge reads 1bar, and steam and water come out release.
• open delivery
• close priming valve

Question 33

Which principle is used to prime the LPP?

Answer 33

Venturi