# N°4 – Pipe head loss chart training – A level

#### Question

Study carefully the flow rate scale.
On the flow rate axis, identify the flow rate of 0.1 [m³/h] (0.44 USgpm).
Note on its right the number 2 which corresponds to 0.2 [m³/h] (0.88 US gpm).
On the flow rate axis, identify the flow of 10 [m³/h] (44 US gpm).
To what flow rate does the number 2 correspond, situated on the right of the flow of 10 [m³/h] (44 US gpm)?
It corresponds to 20 [m³/h] (88 US gpm)It is necessary to take into account the reference values which are powers of 10 (10-1 = 0,1 ; 100 = 1 ; 101 = 10 ; 102 = 100 ; …) ; the value obtained is thus: 2 x 10 = 20 [m³/h].

#### Question

Study carefully the head loss chart
– what is the head loss unit?
– refer to the value of 10 [daPa/m]. What head loss (in [daPa/m]) corresponds to the value indicated 2, just below?
– Unit: [daPa/m] or [mmCE/m]
– 2 means 20 [daPa/m]It is necessary to take into account the reference values which are powers of 10 (10-1 = 0,1 ; 100 = 1 ; 101 = 10 ; 102 = 100 ; …) ; the value obtained is thus: 2 x 10 = 20 [daPa/m].

#### Question

Using the head loss chart above, indicate the maximum flow that is reasonable to transmit through the pipes, according to their DN (for a maximum of 20 [daPa/m]).
By reading the chart, we obtain: