
SAFETY WITHOUT COMPROMISE
Available at Alpha Process Sales - All Locations & Murray Engineering - Northern Texas
With over 95 years in the business, Protectoseal is the industry-leading manufacturer of high-quality safety products. Our vapor and flame control technologies are deployed to ensure protection in some of the most stringent industrial applications found throughout the world. Every day, on every continent, our dependable line of products prevent volatile emissions from escaping and damaging the environment while guarding facilities and employees against dangerous flame and explosive events.
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ANCILLARY TANK EQUIP.

Safety Shut-off Valve

Fuel Tank Safety Caps

Automatic Tank Gauge

Safety Shut-off Valve
VAPOR & FLAME SOLUTIONS
PROTECTOSEAL FEATURED PRODUCT
END-OF-LINE PRESSURE/VACUUM CONSERVATION VENT - IMPROVED PERFORMANCE
Protectoseal Series 8540G Improved Performance, Aluminum, End-of-Line Pressure / Vacuum Breather Vent provides quicker pressure pallet lift, and improved flow performance at low overpressures just above the relief set point. This provides the benefit of higher flows at lower overpressures which can be beneficial in storage tank vapor control schemes requiring tight operating bands with the tank’s emergency relief vents, tank blanketing valves and other associated devices in their vapor control system.
Features & Benefits
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“Air-cushion” pallet design for low leakage performance of no more than 1 SCFH at 90% of the set pressure
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Pallet assembly guides and center pallet stem guide to ensure proper alignment of pallet assembly on the seat and smooth lifting and reseating action
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Unique design allows for quick lift of the pallet and higher flows at lower overpressures
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Automatic condensate drainage design to mitigate freezing, binding and clogging
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Swing-bolt design facilitating inspection and easy maintenance
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Serialized unit and associated weights for easy identification and traceability
SPECIFICATIONS
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Sizes: 2” (DN 50) through 12” (DN 300)
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Flange Connections: Mates with 125# ANSI and DIN PN 16
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Materials: Aluminum (refer to Series 8540H for other materials)
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Certifications: Conforms with the latest ATEX Directive
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Standard Setting Range*: Pressure: 0.5 – 48 oz/in2 | 2.15 – 206.84 mbar
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Standard Setting Range*: Vacuum: 0.5 – 23 oz/in2 | 2.15 – 99.11 mbar

Spring Operated Tank Blanketing Valve, ½″

Pilot Operated Tank Blanketing Valve, 1″

End-of-Line Conservation Vent and Flame Arrester

Spring Operated Tank Blanketing Valve, ½″
PRESSURE & VACUUM RELIEF VENTS
Pressure / Vacuum Relief Vents are employed where it is necessary or desirable to reduce evaporation of tank contents to atmosphere. These vents are generally designated as the conservation type. They are typically mounted to a flange or pipe that connects to the vapor space (space within the tank that is above the liquid surface) of a storage tank. The pressure in this vapor space increases or decreases as liquid is pumped into or out of the tank, respectively. Atmospheric temperature changes cause an expansion or contraction of the vapors in this space, again resulting in pressure increases or decreases.
These vents are factory set to your specifications so that the pallet assemblies in the housings open when specific pressure and vacuum levels are sensed. The set points for these vents are achieved either by weight loading or spring loading of the pallet assemblies, depending on the setting required. The tank’s vapor space pressure/vacuum works in opposition to the force (weight or spring) applied to the pallet assemblies. Once the excess pressure or vacuum condition has been relieved, the pallet assemblies reseal automatically. The tank’s vapor space is always maintained within the safe range of its pressure and vacuum operating design limits.
Series No. 830
End-of-Line Conservation Vent and Flame Arrester
Series No. 830E
End-of-Line Conservation Vent and Flame Arrester – ATEX / CE / ISO
Series No. 3908
Pressure and Vacuum Relief Thief Hatch
Series No. 5200G
Weatherhood Free Vent
Series No. 6240
End-of-Line Vacuum Vent
Series No. 8540G
End-of-Line Pressure / Vacuum Conservation Vent – Improved Performance
Series No. 8540H
End-of-Line Pressure / Vacuum Conservation Vent
Series No. 8740
In-Line Pressure and Vacuum Relief Vent
Series No. 16240
Side-Mounted Vacuum Relief Vent
Series No. 17800
Pipe-Away Pressure Relief Vent
Series No. 18540H
Pipe-Away Pressure Relief Vent
Series No. 56000
PIN-TECH™ Bubble-Tight <500 ppm Pressure Relief Vent
EMERGENCY RELIEF VENTS
In addition to the normal venting capacity provided by Protectoseal’s Pressure / Vacuum Relief Vents and/or Flame Arresters, every large above ground flammable liquid storage tank should be provided with some means of relieving excessive internal pressure caused by exposure of the tank to a fire. Depending upon the strength of the tank structure, a vent sized to handle the normal venting requirements (for day-to-day operations) may be inadequate to handle the abnormal vapor efflux generated by heat from an exposure fire.
When a fire occurs near a flammable liquid storage tank, heat transmitted through the tank wall to the contents will cause the liquid to vaporize readily. In the case of petroleum based products, this vaporization may amount to roughly 30 or more cubic feet of vapor for every gallon of solvent vaporized. This generates a relatively high pressure within the confined area of the tank’s vapor space. In the absence of sufficient emergency relief a tank rupture could occur, with disastrous effect on life and property and the environment.
Explosions caused by such conditions may be readily avoided by providing adequate emergency relief vents which permit the vapors to escape from the tank. These emergency vents usually include pallet assemblies which are weighted to stay closed under normal pressure conditions and which open only when a predetermined pressure is attained, thus relieving the abnormal volume of vapor generated under the fire conditions described above. Emergency relief vents should be sized and specified in accordance with NFPA 30 Flammable and Combustible Liquids Code (Emergency Relief Venting for Fire Exposure for Above Ground Storage Tanks).
Series No. 7800
End-of-Line Emergency Pressure Vent
Series No. 51700
Hinged Emergency Pressure Relief Manhole Cover Vent
Series No. 52600
Emergency Pressure and Vacuum Relief Vent
Series No. 53300
Emergency Pressure Relief Manhole Cover Vent
Series No. 54000
Spring-Loaded Emergency Pressure Relief Vents
FLAME ARRESTERS
Flame arresters are passive, mechanical devices installed on a storage tank nozzle or in a vapor piping system. Its primary function is to allow gases to pass through during normal operating conditions, but stop a flame in order to prevent an explosion or fire propagation under emergency situations. Stopping the flame protects the storage tank, or the equipment located in the piping system, from the catastrophic damage that may result from an uncontrolled ignition. For industries that handle, store, transfer and collect hazardous liquids, a single unchecked flame can cause extensive damage to both plant and equipment, not to mention the risk of personal injury or loss of life.
A variety of arrester designs are available. The selection of the appropriate arrester depends on the flammable properties of the vapor/air mixture, operating conditions as well as how and where the arrester is installed with respect to the potential ignition source. Shown below are three primary categories of arresters that are available in the market. The user must be assured that the arrester selected has been tested for conditions that match or exceed the intended application. Protectoseal flame and detonation arresters are developed in accordance to the testing / listing criteria of nationally recognized independent agencies such as Underwriters Laboratories, Inc. (UL), Factory Mutual Research (FM) and the United States Coast Guard (USCG). Also available are models that are type approved according to the latest ATEX Directive and ISO 16852.
Series No. 670 / 6670
End-of-Line Deflagration Flame Arrester
Series No. 670E
End-of-Line Deflagration Flame Arrester – ATEX / CE / ISO
Series No. 860
End-of-Line Rectangular Plate Flame Arrester
Series No. 27000 / 29000 / 31000
End-of-Line Crimped Metal Flame Arresters
Series No. 4950
Vent-Line / In-Line Deflagration Flame Arrester
Series No. 30000
Vent-Line Deflagration Flame Arrester
Series No. 45000E / 46000E
In-Line Deflagration Flame Arresters, ATEX / CE / ISO
In-Line Detonation Flame Arresters
“Detonation” arresters are especially designed to stop and extinguish detonations, confined deflagrations and unconfined deflagrations.
TANK BLANKETING VALVES
Tank Blanketing Valves provide an effective means of preventing and controlling fires in flammable liquid storage tanks. Vapors cannot be ignited in the absence of an adequate supply of oxygen. In most instances, this oxygen is provided by air drawn into the tank from the atmosphere during tank emptying operations.
Tank Blanketing Valves are installed with their inlet connected to a supply of pressurized inert gas (usually Nitrogen), and their outlet piped into the tank’s vapor space. When the tank pressure drops below a predetermined level, the blanketing valve opens and allows a flow of inert gas into the vapor space.
The blanketing valve reseals when pressure in the tank has returned to an acceptable level. The blanketing gas contains no air. No supply of air (Oxygen) is allowed to enter the tank. The vapors, therefore, never form a flammable mixture.
Tank Blanketing Valves help maintain the vapor space in a non-flammable condition, and also provide make-up gas to insure that the tank’s vapor space is not subjected to a vacuum.
Series No. 10
Pilot Operated Tank Blanketing Valve, 2″
Series No. 20
Pilot Operated Tank Blanketing Valve, 1″
Series No. 30
Emergency Pressure and Vacuum Relief Vent
LIQUID LEVEL MONITORING
SPECIALTY VALVES & FITTINGS
Series 782
Air Dryer provides a simple, relatively inexpensive means of extracting unwanted moisture from make up air entering a storage tank.
Series 4970D and 4980D
Gauge Hatches provide ready access to storage tanks for gauging or sampling.
Series 3000
Internal Safety Valves are intended for use on storage tanks containing flammable or combustible liquids. Safe and efficient, the valves help protect the tanks and their contents and provide valuable aid in accident prevention.
Series 7300D
Overflow Valve eliminates an open overfill pipe connection into the vapor space of the tank.
Series 660
Water Drain Valves are designed to provide maximum flow and assure complete draining when relieving tanks of bottom water accumulated during normal breathing.
Series No. 4276
Rim Vents are designed for use on floating roof tanks. They are mounted around the rim of the tank roof system and provide casual relief for any pressure accumulations under the pontoon sections of the roof.
FUEL TANK SAFETY CAPS
Fuel Tank Safety Caps
Combination safety fuel cap, pressure / vacuum relief device is designed for installation in fuel tank openings of gasoline or diesel-powered industrial trucks and equipment such as forklifts, tractors and airport ground support equipment, The perforated metal flash arrester keeps a flame from entering the tank, thereby preventing explosion of the confined vapors within the tank. Safety fittings provide sufficient pressure relief to prevent tank rupture and sufficient vacuum relief to facilitate gas flow from the tank. The spring-loaded, self-closing cap protects against evaporation losses.
SAFETY SHUT-OFF VALVE
Series No. U1-45
Heat Actuated Safety Shut-off Valves are specifically designed for installation in the withdrawal lines of flammable or combustible liquid storage tanks. The valves are normally held in the fully open position by a heat-activated element mechanism. In the event of exposure to an external fire source, the element is activated and the valve is closed securely by an internal spring. The flow of liquid through the withdrawal line is stopped.