NANO

FUEL SYSTEM 5 B. CYLINDER VALVE: Function: Cylinder valve is an electronically and manually controlled shut-off valve fitted on the cylinder which can open or shut-off the CNG supply and which incorporates a bust disc and a fusible material. The main function of this valve is to shut off gas flow from the cylinder in to the system when the ignition of the vehicle is off. Cylinder valve comes with 12 volts solenoid coil. It is normally closed and activates only when electric current is passed through the coil. The solenoid coil / valve is an added safety feature. In addition, Cylinder valve comes with 3 inbuilt safety features, namely an excess flow device, a burst disc and a fusible plug. These safety devices provide protection in case of line rupture, over pressure and fire. The burst disc and the fusible plug are pressure relief devices (P.R.D.) which operate independently. Constructional details: The Cylinder valve consists of following components. Excess flow device: This is an inbuilt safety device which activates on excessive increase of the flow rate of gas. Burst Disc: This is a pressure relief device which activates in case of excessive increase of gas pressure in the tank. Fusible plug: Fusible plug is also a pressure relief device. This is thermal activated in case of excessive rise in temperature near the valve. Solenoid coil / Valve: Solenoid coil is connected with the ignition circuit of the vehicle. It is normally closed and activates only when an electric current is passed through the coil and there by it opens the path for gas to flow freely into the high pressure line. The solenoid coil is operated by CNG ECU.If any leakage is observed by the CNG ECU in high pressure line, it will automatically shut-off the cylinder valve and stops the supply of CNG. When the solenoid valve is closed, the gas can be filled into the cylinder but cannot be withdrawn from the cylinder. Vent tube / Ventilation hose: Vent tube is used for the ventilation purpose so that when there is any leakage through cylinder valve, the gas is vented out of the passenger cabin in to the atmosphere. Ventilation hose covers the entire length of ¼” stainless steel tube in passenger compartment. Mounting location: The cylinder valve is fitted to CNG cylinder which is located under driver & co-driver seat. Manual ON / OFF Knob or Tap: Cylinder valve is an automatic valve but a manual knob is also provided as an additional safety for the opening and closing the path of the gas. This manual tap is normally kept open and it can be closed at the time of maintenance / service or in case of leakages. The Knob should always be in open position to allow the flow of CNG to Engine. In the close position of the knob, CNG supply to the engine is stopped. Also gas cannot be filled into the cylinder at knob closed position. If the cylinder subjected to impact or fire damage, it should be inspected and retested. On top of the manual knob of the valve, the opening and closing directions are clearly marked for the operator to have a visual indication of the direction for opening and closing. To open the valve, the knob must be turned in the anti-clockwise direction and to close, the knob must be turned in the clockwise direction.