61fSTOP "The Stopper" Overfill Prevention Valves

The OPW 61ƒSTOP Overfill Prevention Valve ("The Stopper") is designed to prevent overfilling of aboveground storage tanks by providing a positive shut-off during a pressurized-fill (pump-on fill) delivery.
"The Stopper" threads into the fill opening and is an integral part of the fill tube. The OPW 61ƒSTOP is fully adjustable to allow for easy installation in new or existing aboveground tanks of various heights and storage capacities.
The Stopper is a single-action, complete shut-off valve. When the liquid level rises to your specific, pre-determined tank capacity, the valve mechanism is released and automatically closes with the flow of the product. Any excess product left between the valve and the fuel delivery coupler is drained into the tank through internal drain vents. The drain vents on the 61fSTOP act as an anti-siphon, by introducing air/vapor into the fill line, to help isolate the tank from a potential siphon due to a broken or leaking fill pipe.
The 61ƒSTOP, available in either 2" or 3" full-flow models, maximizes flow rates and minimizes delivery times. The 2" 61ƒSTOP requires a 4" tank opening and minimum tank ullage (space from the top of the stored product to the inside top of the tank) of 8" on the 61ƒSTOP-1000 Cylindrical Float model and a minimum ullage of 4" on the 61ƒSTOP-2000 Float Arm model. The61ƒSTOP-1000, with the cylindrical float, eliminates the need to position the valve to avoid tank walls or cross-bracing. The 61ƒSTOP-2000 with the float arm allows for increased usable storage capacity in the tank, and is well-suited for small capacity rectangular ASTs. The 3" 61ƒSTOP requires a 6" tank opening and incorporates a cylindrical float requiring 8" of tank ullage space. The 3" Stopper is a high-flow unit that can accommodate flow rates over 400 gallons per minute (depending on pump capacity).
The 61ƒSTOP, available in either 2" or 3" full-flow models, maximizes flow rates and minimizes delivery times. The 2" 61ƒSTOP requires a 4" tank opening and minimum tank ullage (space from the top of the stored product to the inside top of the tank) of 8" on the 61ƒSTOP-1000 Cylindrical Float model and a minimum ullage of 4" on the 61ƒSTOP-2000 Float Arm model. The 61ƒSTOP-1000, with the cylindrical float, eliminates the need to position the valve to avoid tank walls or cross-bracing. The 61ƒSTOP-2000 with the float arm allows for increased usable storage capacity in the tank, and is well-suited for small capacity rectangular ASTs. The 3" 61ƒSTOP requires a 6" tank opening and incorporates a cylindrical float requiring 8" of tank ullage space.
- A special crossbar tank-inlet adaptor – is provided with each Stopper to provide for tight-fills and help prohibit open-fills. Mounting hardware, upper drop tube and 14" lower drop tube provided (longer-length drop tubes can be purchased or added).
- Completely Automatic Operation – No pre-checks to perform, no resets, and no overrides to be broken or abused.
- Direct or Remote-Fill Compatible – Fuel delivery couplers can be connected directly to the 61ƒSTOP, or steel pipe can be threaded into the top of the valve and piped to a remote location where the couplers are contained in a 211-RMOT Spill Container.
- Integral Anti-Siphon Valve – Drain vents on the 61ƒSTOP act as an anti-siphon, by introducing air/vapor into the fill line after the valve actuates, to help isolate the tank from a potential siphon due to a broken or leaking remote-fill pipe.
- 150 psi (10 bar) Pressure Rated* with Low Pressure Drop – To enable quick, safe delivery of fuel into the tank.
- 25 GPM (95 L/min) Minimum Flow Rate Required.
- UL and ULC Listed – To satisfy Third Party accreditation requirements of many jurisdictions.
- CARB Approved
*OPW does not recommend pumping pressures above 100 psi for Class 1B fuels and we make no warranties for products used in conjunction with the 61ƒSTOP.
NOTE: OPW recommends the use of the 61ƒSTOP with clean product only. Debris and other products such as contaminated waste oil may cause improper operation of the valve.
NOTE: The 61ƒSTOP can be used in gravity drop provided the minimum flow rate is maintained. A tight shut off is not achieved in the closed position. However with a minimum tank size of 1,000 gallons, the leak rate will provide a 30 minute warning before the tank is full.
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61fSTOP-1000 | 2" Cyl. Float | |
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61fSTOP-100M | 2" Cyl. Float for Methanol | |
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61FSTOP-100M | 2" Cyl. Float for E85 | |
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61fSTOP-2000 | 2" Float Arm | |
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61fSTOP-200M | 2" Float Arm for Methanol | |
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61FSTOP-200M | 2" Cyl. Float for E85 | |
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61fSTOP-3050 | 3" Cyl. Float | |
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61fSTOP-305A | 3" Cyl. Float for Aviation, Methanol and AV-GAS | |
CARB APPROVED AST OVERFILL PREVENTION VALVE | |||
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61ƒSTOP-1000T | 2" NPT with cylindrical float | |
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61ƒSTOP-2000T | 2" NPT with float arm | |
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61ƒSTOP-3050T | 3" NPT with cylindrical float |
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