Unigas HS5, Руководство по установке и эксплуатации

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APPENDIX - COMPONENTS CHARACTERISTICS 26
SUNTEC AT2 PUMP
The SUNTEC AT2 oil pump features 2 mode pressure operation and incorporates a blocking solenoid valve with in-line cut-off function.
Switching between low and high modes is assured by a 2nd integral solenoid valve.
Operation
The gear set draws oil from the tank through the built-in filter and transfers it to the nozzle line via the cut-off solenoid valve. Pressure regulation
is assured by two spool valves, one for each pressure mode. Switching between low and high pressure is assured by a "normally open" by-pass
solenoid valve. When this solenoid is non-activated, a by-pass channel is open, allowing the normal functionning of the low pressure valve
which sets the nozzle pressure. When this solenoid is activated, the by-pass channel is closed, thus pressure will build up on both sides of the
low pressure valve eliminating its effect, and the high pressure valve now determines the nozzle pressure.
The blocking solenoid valve of the nozzle line is of the "normally closed" type. This design ensures extremely fast response and the switching
can be selected according to the burner operating sequence and is independant of motor speed. When this solenoid is non-activated, the valve
is closed and all oil pressurised by the gear set passes through the regulators to suction or to the return line, depending upon pipe arrangement.
As soon as this solenoid is activated, oil passes to the nozzle line at the pressure set by the pressure regulating valves.
In two pipe operation, the by-pass plug must be fitted in the return port, which ensures that the oil dumped by the regulating valves is returned to
the tank and the suction line flow is equal to the gear set capacity. Bleeding in two pipe operation is automatic (it is assured by a bleed flat on
the pistons), but it may be accelerated by opening a pressure port.
In one pipe operation, the by-pass plug must be removed, and the return plugged. Oil which is not required at the nozzle is returned directly to
the gear inlet via the pressure regulating valves, and the suction line flow is equal to the nozzle flow. A pressure port must be opened to bleed
the system.
TECHNICAL SPECIFICATIONS
Mounting hub mounting according to standard EN 225
Connection threads cylindrical according to ISO 228/1
Inlet and return G 1/4"
Nozzle outlet G 1/8"
Pressure gauge port G 1/8"
Vacuum gauge port G 1/8"
Valve function pressure regulation
Strainer: open area: 14 cm 2 (AT2 45/55/65)
20 cm
2
(AT2 75/95)
opening size: 150 µm
Shaft Ø 8 mm according to EN 225
By-pass plug inserted in return port for two-pipe system; for one
pipe system
Weight 1,3 kg
HYDRAULIC SPECIFICATIONS
Nozzle pressure range Factory setting
Low pressure: 8-15 bar 9 bar
High pressure: 12-25 bar 22 bar
* AT2 75/95 : ppressure obtained with 10,5 GPH open noz-
zle
Viscosity range
2 - 12 cSt
Max. fuel temperature. 60°C into the pump
Inlet pressure 2 bar max.
Return pressure 2 bar max.
Suction height max. 0,45 bar to avoid air
separation from oil
Rated speed 3600 rpm max.
Starting torque 0,10 N.m (AT2 45/55) -
Key
1 By-pass solenoid valve, closed
2 By-pass solenoid valve, open
3 Blocking solenoid valve, open
4 Nozzle
5 Blocking solenoid valve, closed
6 By-pass plug, removed
6A By-pass plug, inserted
7 Return to suction
8 Closed return
9 Shaft seal
10 Return
11 Suction
12 Pressure outlet or pressure
gauge port
13 Gear set
14 High pressure adjusting screw
14a Low pressure adjusting screw
15 Vacumeter port
A Oil under suction
B Oil under pressure
C By-passed oil returned to tank or
to suction