244000391 - VALVE ASSEMBLY ON TANK
No maintenance operations can be carried out on the valve assembly on the tank flange usually known as the "valve assembly".The exception to this is the solenoid valve coil; all other operations must be entrusted to the tank supplier.The positioning of the valves in the tank allows them to be incorporated in a single flange protected by a sealed chamber.Each solenoid valve is electrically supplied by the ignition via a special relay and is earthed through the inertia switch.When the solenoid valve is de-energized (engine off or running on petrol), the route to the injectors is closed.When the solenoid valve is energized (ignition key in ON position and running on LPG), the route to the injectors is open, placing the canister in contact with the engine fuel supply system.The functional assembly components are listed below:Normally closed type solenoid valve (1) located on the supply valve (2) which, if there is no electrical supply, prevents the LPG from flowing from the canister to the engine.Flow restricter located on the solenoid valve; if the supply pipe breaks accidentally on account of the different in pressure, it intervenes, preventing the LPG from completely draining suddenly.The flow restricter is located inside the valve so that it remains inside the canister, making sure that it works even if the solenoid valve breaks due to an impact.Safety device (5) which, if the pressure inside the tank exceeds 27 bar (for example if there is a fire in the vehicle), allows the controlled escape of LPG preventing an explosion.Multivalve assembly (4) consisting of:Single-acting return valve (calibrated port) (3) located on the return line from the injectors. The valve guarantees the LPG pressure inside the circuit remains at a set value.A mechanical valve normally known as the "80% safety valve" that operates during filling; when the volume occupied by the liquid gas inside the tank reaches 80% of the total volume of the actual tank, this valve automatically stops the LPG refilling.This operating condition is vital, as the temperature increases, to allow the liquid to increase in volume with a consequent increase in pressure, without adversely affecting the safety conditions.
 | If this valve is not working properly, the tank could become too full resulting in a dangerous increase in the internal pressure. |
 | If the canister becomes too full when refilling with LPG (which, starting from a gas level of zero, means that the maximum quantity of 45.6 litres of LPG has been exceeded), replace the liquid level restricter safety valve in the canister (80% valve). The nominal capacity of the tank is 57 litres, corresponding to a practical capacity of 45.6 litres. |
LPG STORAGE SYSTEM COMPONENTS
| Flange | 112 mm diameter flange housing the multivalve assembly |
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| LPG supply valve | Operated by a specific solenoid valve, 12V power supply, 1st absorption, closed if there is no electrical supply, sealed, with pressure decrease values that vary between 0.2 and 0.65 bar/h (with a maximum pump capacity of 120 l/h) |
| LPG return valve | Valve with pressure decrease values that vary between 0.2 and 1.8 bar/h (with a maximum pump capacity of 120 l/h) |
| Pressurizing valve | Valve with LPG pressurizing prevention when 80% of the maximum tank volume is reached: it takes about 3 minutes to fill a tank with a capacity of around 50 litres |
| Safety valve | Intervention pressure (tank pressure) less than or equal to 27 bar; allows the controlled escape of LPG |
| Flow restricter valve | Located inside the supply valve, intervention pressure 0.9 bar (in accordance with regulation E67-01) , it limits the flow rate if the pipes are broken |
| Electric cable duct | 4 pin for pump connection, two for level transducer connection, sealed |
| LPG pump | Submerged with drip tray and jet pump, complete with filter, 7 - 15V power supply, max absorption 6°, max flow rate 120 l/h, operating temperature range -40°C - 80°C |
| Level gauge | Reed relay electronic transducer (5 mm reed), 12V power supply, ohmmic resistance with tank empty %gt; 900%Ohgr; ohmmic resistance with tank full %gt; 3000 %Ohgr; temperature operating range -20°C - 80°C, max. operating pressure 70 bar |
