18
OIL DELIVERY
Rated speed : 2850 rpm - Viscosity : 5 cSt - Pressure : 9 bars
The annexed charts (Page 20) give the maximum length (in meters) of suction
line as a function of three variables :
• lift between fuel unit and tank (H),
• nozzle capacity or pump type,
• pipe diameter (d),
for an altitude of 200 m above sea level and 0,45 bars vacuum.
The length indicated (intersection of horizontal lines and columns) assumes that
the fitting of four right angle bends, one stop valve,one non return valve have
been done. If additional restrictions exist (particularly the filter in the suction line),
the length must be reduced accordingly. Only previously specified pipe sizes can
be used, bigger pipes are not suitable.
Altitude correction :
if X is the altitude (different from 200 m),
- Lift system : add the value (X-200)/1000 to the real lift height "H" , to obtain the
equivalent lift, then determine the maximum length with the annexed charts.
-Siphon feed system : reduce the real head height "H" by (X-200)/1000.
Ex :
AS67 pump in two pipe lift system, with lift height = 1,5 m, altitude = 700 m,
pipe diameter = 8 mm .
Equivalent lift height : 1,5 +(700-200)/1000 = 2 m ,
Maximum pipe length = 13 m.
Pressure correction :
only for one pipe system.
If P is the pressure (different from 9 bars), use the theoretical equivalent nozzle
capacity = (VP /3) x real nozzle capacity.
Ex :
One pipe lift system, with nozzle = 4GPH, pressure = 12 bars, pipe diameter
= 6 mm , suction height = 2 m;
Equivalent nozzle capacity = (12/3)x4 = 4,62 GPH. The maximum pipe length is
comprised between 30 m (corresponding to 4 GPH) and 20m (corresponding to
6 GPH), that means around 27 m .
PUMP PRESSURE REGULATION
A pressure gauge is connected at the connection point No. 5 for pressure
monitoring. A vacuum gauge is connected at the connection point No. 3 for
vacuum monitoring. Any bleeding operation must be performed during the burner
operation until the fuel flows without any air bubbles being observed from the
pressure gauge connection point when it is loosened slightly. Re-tighten this
connection before increasing the pump pressure. The pump pressure is
increased by turning the pressure adjusting screw (5) clockwise.
The pump
pressure can be regulated up to 30 bars.