The Protectoseal Series No. 120 and No. 150 units, when installed in storage tank fill openings, protect tank contents from external ignition sources during filling operations. When equipped with flash arresters long enough to reach within 2" of tank bottom, these fittings permit rodding and sampling. They can also be used as additional fittings exclusively for rodding and sampling when a remote fill pipe location prevents rodding and sampling directly through the fill opening. It is recommended that the tank also be equipped with a suitable Protectoseal flame arrester/venting device, such as the Series No. 830, 860 or 670 to prevent excessive pressure or vacuum accumulations within the tank during filling and emptying procedures.

The Series No. 120 fitting is a combination unit. It is designed with a flash arrester to protect tank contents against exterior sources of ignition during filling operation. It also provides supplemental auxiliary pressure and vacuum relief. The fitting may be secured with a padlock.

The Series No. 150 fitting is designed for use when it is necessary to have the fitting mounted flush with the floor or ground surface. Threaded, gasketed covers provide positive sealing. Lugs are provided for mounting of a padlock to prevent unauthorized removal of the covers. Flash arrester provides protection from external ignition sources.

Protectoseal Series No. 400 Units install in storage tank rodding and sampling openings and protect tank contents from fire during rodding and sampling operations. Safety tube flash arrester assemblies prevent the propagation of fire into the tank. They are particularly suitable for installation on storage tanks containing solvents and light oils.

Small pressure and vacuum relief valves in the head assembly provide supplemental venting capacity under operating and emergency conditions. Valves open and close to permit only that intake or outlet relief necessary to keep interior pressures within permissible working limits. The vacuum relief valve controls the intake of air, whereas the pressure relief valve controls the escape of vapors to the atmosphere. The need for additional venting equipment must be evaluated on an individual case basis.

The Protectoseal Series No. 500 Flash Arrester Fill Units are particularly suited for installation in storage tank openings where tanks are filled by direct connection from trucks or railroad tank cars. These fittings include a perforated metal flash arrester to protect tank contents against fire and explosion from external sources of ignition when the fill hose is not connected. Installation is made by simply threading the fitting directly onto the tank fill pipe. The hose from the supply source can then be connected to the external NPT threads on the head assembly. Liquid flows through the perforated metal flash arrester into the tank. When the hose is removed, this flash arrester prohibits ignition of the vapors inside the tank if some external ignition source is present. When the fill line is not in use, the opening should be covered by the cast threaded cap that is provided. This cap may be padlocked for added security. It is recommended that the storage tank be fitted with a Protectoseal flash arrester/venting device, such as the Series Nos. 830, 860 or 670. When properly sized and applied, these supplemental vents will prevent excessive pressure or vacuum accumulations within the tank during filling and emptying.

Protectoseal Series No. 660 Water Drain Valves are designed to provide maximum flow and assure complete draining when relieving tanks of bottom water accumulated during normal breathing. Units are mounted to the tank flange connection. An NPT thread connection is provided to allow for attachment of a drain pipe (dip tube) to the valve inlet within the tank. Swivel design outlet spout permits downward positioning after valve has been properly mounted in the tank flange. Unique spring loaded poppet action allows for flushing of foreign matter from the internal sealing surface of the valve. The external, main valve seat may be inspected and repaired while the tank is in service, with sealing being provided by the internal valve mechanism.

Series No. 782, Air Dryer

The Protectoseal No. 782 Air Dryer provides a simple, relatively inexpensive means of extracting unwanted moisture from make up air entering a storage tank. It is recommended for tanks and systems where the installation of an expensive central air drying or inert gas system cannot be justified. Incoming air (required for normal venting or during liquid pump-out) passes through a highly efficient desiccant material before entering the tank. The desiccant is capable of absorbing a considerable amount of moisture before it approaches its saturation point, whereupon it can be either replaced or regenerated.

The Protectoseal Series No. 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. The design and operation of the units satisfy those regulations requiring flammable or combustible liquid tanks to be equipped with valves that close automatically when subjected to fire.


The Protectoseal Internal Safety Valve may be manually opened or closed. It is normally held open by a turnbuckle and a fusible link. In the event of fire, the fusible link melts at 160°F. When the link melts the valve is quickly closed by the released spring action. The Internal Safety Valve provides positive means of stopping full flow through the pipe during an emergency fire situation. The valve is not intended to serve as a primary shut-off device.

The Protectoseal Series No. 4970D and 4980D Gauge hatches provide ready access to storage tanks for gauging or sampling. The Series No. 4980D Gauge Hatch also provides some pressure relief as well as supplemental emergency venting capacity. The lockdown mechanism on the Series No. 4970D makes it particularly suited for use on tanks with normal operating pressures under 3 PSIG. Tightening the thumb screw holds the cover securely in place thereby minimizing leakage and evaporation losses. The gauge hatches are intended for use in applications where the fire protection afforded by flame arresters is not considered necessary.

Series Nos. 4970D / 4980D Gauge Hatches consist of a hinged, self-closing cover which sits on a flanged base. Placing a foot on the serrated treadle opens the cover to a full 75° to 80°, permitting inspection and easy entry for gauging or sampling. Removing foot allows cover to return to a closed position.

Protectoseal Series Nos. 40000 / 41000 Liquid Level Indicators are used for accurate liquid level gaging of fixed roof tanks storing oil, water, solvents and other products. The units are designed for simple, easy installation for "tanks-in-service" or "tanks-out-of-service" and to provide a maximum of trouble-free service. They are especially recommended for applications that require a low cost, low maintenance method of liquid level gaging. Series 40000 / 41000 Indicators are float-actuated, and have a steel target that runs up and down a calibrated board to register the tank liquid contents level. The board is mounted outside of the tank and has bold, legible markings to permit quick, convenient readings.

Protectoseal Series No. 42000B Automatic Tank Gauge provides high gauging accuracy in measuring liquid level in all type of low pressure cone roof, floating roof and underground tanks. They help prevent vapor loss and reduce the time needed for taking readings. The float-operated gauges are compact and have large, legible numerals which permit quick, accurate readings of the displayed liquid level. The gauges may be used on tanks up to 65' high and for pressure ranges up to 50 PSIG. Easy to install, they can be conveniently mounted at the top of the tank or mounted at the side of the tank for ground reading. Float movement activates a negator spring motor that rotates the liquid level indicating wheels to their appropriate positions in the viewing window.