0000110982/231018/A SER
EN - 11
6
DISPOSAL
After life of the product, dispose it of in accordance with state
or local regulations.
7
PRESSURE LOSS CALCULATION
The fall of pressure in a air duct system or in a hose is mainly
determined by the air velocity in that system.
The higher the velocity is, the higher the pressure loss will be.
And the higher the pressure loss is, the less air the fan will
extract. See
fig. 7.1
for a Pressure Loss Chart to identify a
suitable fan regarding the relationship between airflow and
pressure loss.
In a ventilation system with many extraction devices and long
suction ducts, you can minimise pressure loss by increasing
the size of the ducting. This will also ensure even velocity
throughout the system.
Hose diameter
Length
A
Ø 100 mm (4 in.)
7,5 m (24.7 ft)
B
Ø 100 mm (4 in.)
10 m (33 ft)
C
Ø 100 mm (4 in.)
12,5 m (41 ft)
D
Ø 125 mm (5 in.)
7,5 m (24.7 ft)
E
Ø 125 mm (5 in.)
10 m (33 ft)
F
Ø 125 mm (5 in.)
12,5 m (41 ft)
G
Ø 150 mm (6 in.)
7,5 m (24.7 ft)
H
Ø 150 mm (6 in.)
10 m (33 ft)
I
Ø 150 mm (6 in.)
12,5 m (41 ft)
J
Ø 200 mm (8 in.)
10 m (33 ft)
Note: 75 mm (3 in.) hoses are not available in North America.
A
B
C
D
E
F
G
H
I
J
Airflow Volume: General Guidelines
Vehicles serviced
m
3
/h
(cfm)
Hose
diameter
Automobile / Motorcycles
460-510
(270-300)
Ø 100 mm (4 in.)
Trucks (Public Works,
Rental Fleets, etc.)
850-935
(500-550)
Ø 125 mm (5 in.)
Heavy Duty Trucks
1100-1360
(650-800)
Ø 150 mm (6 in.)
Off-Road (Constr.,
Compressor Tests, etc.)
1700-2400
(1000-1400)
Ø 200 mm (8 in.)
When 1200 to 1350 m
3
/h is needed, Plymovent recommends a
150 mm (6 in.) hose. A 200 mm (8 in.) hose can be used for
larger applications, as it supports larger engines operating
under load. For those cases, the exhaust flow and temperature
increase dramatically.
Air velocity in ducting: 17,8 - 22,9 m/s (3500 to 4500 fpm).
The chart below shows the pressure loss in the hose reels a
different airflows. Refer to the Airflow Volume: General
Guidelines table below for the vehicle, airflow and hose
diameter guidelines. The curves show these combinations of
hose reel/hose diameter/hose length (uncoiled position).
We recommend that you confirm existing exhaust
temperatures to ensure proper hose, fan and
airflow selection.
Fig.7.1 Pressure loss chart
