Pumping

Question 1

Describe the B class foam induction system

Answer 1

• round the pump proportioning (RPP) system
• diverts a portion of the output from the discharge side of the pump through an eductor
• creates a vacuum at the eductors foam concentrate inlet
• the vacuum draws concentrate through the metering valve for discharge into the suction side of the pump
• the foam induction system feeds B class foam into the pump for use on all deliveries.

Question 2

Describe the A class foam induction system

Answer 2

• post pump injection (PPI) system
• provided by a motorized pump which draws foam from the storage tank
• injects foam to the GP lines, delivery 3 and monitor.

Question 3

What is the name of the pump?

Answer 3

Darley PSRH1250

Question 4

How many stages is the pump?

Answer 4

2 stage pump - normal pressure/high pressure

Question 5

What is the rated performance of the pump?

Answer 5

Normal pressure - 4,500l/m @ 1,000kPa
High pressure - 500l/m @ 4,000kpa

Question 6

What is the high pressure external relief valve set to?

Answer 6

4,200kPa

Question 7

How many (and what type of) primers are fitted to the appliance?

Answer 7

2 x Darley 24v rotary vane electric primers