COMPLIANCE INFO_1986-2002 - Laserfiche WebLink

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THE XLP...3 STEAEAK TEST The Red Jacket XLP leak detector is a pressure -sensing, piston -operated valve designed to indicate a leak in the piping between the leak detector and the dispenser. When the line pressure is at approxi- mately less than 1 psi and the sub- merged pump is turned on, a controlled amount of product (three gallons per Position 1 Pressure F Valve Less than 1 PSI Vented to Tank ♦ii R nn-- i� uii.t ��ul I The Trip or Relaxed Position. Under normal operating conditions, it is assumed that the lines are filled with gasoline. When the system pressure is less than 1 psi, the piston and poppet are in their "down" or "tripped" position. The position of the valve poppet is such as to allow approximately 1-1/2 to 3 GPM flow into the delivery line through a bypass opening in the XLP valve poppet when the submersible pump starts. Since the system is full, pressure builds rapidly and the poppet moves to the leak sensing position assuming there is no leak present. The pressure relief valve prevents any build up of pressure under piston when in trip position by allowing relief of trapped product. hour) is metered through the XLP into the piping system. If a leak is present that equals or exceeds this amount, as much product escapes from the system as is metered in through the XLP. Under this condition pressure cannot build up in the piping system. When a nozzle is opened, a poppet in the XLP moves to a position that restricts the ITO Discharge Line 2. Leak Sensing Position. As the pressure builds to approximately 20 to 22 psi (rapidly) the piston has moved the poppet to such a position as to almost stop the flow into the piping through the XLP valve poppet. In this position, all the flow must then travel around the metering pin which limits it to approxi- mately 3 GPH rate. If a simultaneous loss from the system equals or exceeds this amount, the line pressure will not build beyond this point and the valve will remain in the leak sensing position with the main flow blocked. If there is an attempt to dispense while the valve is in this position, the line pressure will drop, the piston will respond, and the poppet will return to Position 1 where the 1-1/2 to 3 GPM will flow to the dispensers' i c 1-1 flow to approximately 1-1/2 to 3 GPM. This is the indication to the operator that a leak is present.' If there are no leaks, pressure rapidly builds in the system forcing the XLP to open to the full -flow, position. In a system with no leaks, it takes approxi- mately two seconds for a complete test. No further line testing takes place until the line pressure drops below 1 psi. jTo Discharge Line If there is no leakage in the system, the small flow around the metering pin increases the line pressure to 22 psi in approximately two seconds at which point the piston will snap the poppet to Position 3, allowing full flow. Any product relieved through pressure relief valve during trip position will be vented through vent tube to tank. This allows piston to move freely with no back pressure to hamper its movement. 3. Non -Leak Position. This position allows full flow. The poppet will remain in this position as long as the sytem pressure remains above 1 psi. At less than 1 psi, the poppet will return to Position 1 and the next time the pump is activated, the XLP will perform a line test. 'If the dispensing system (the solenoid valve and the nozzle) is opened previous to the completion of the line test, the XLP will detect this opening as a leak and restricted flow will result. Closing of the nozzle(s) for a period of time, adequate to allow completion of the line test, will allow the XLP to open. This, in turn, will allow full flow providing there is no additional escape for fuel in the system. • 0 Per the above process, this product is designed and sold to detect leaks of approximately 3GPH or greater only. For leaks of less than approximately 3GPH, please consult with your Marley Pump Company • representative. XLP-31010/92 M A R L E Y THE MARLEY PUMP COMPANY A Division of Tfte Marley Company