Abstract: A manhole rim and cover assembly includes a rim formed with an annular upwardly projecting lip extending around its central opening with a shoulder projecting radially inwardly from the lip at a location spaced below its upper edge. A cover has circumferentially spaced circumferential segments projecting downwardly from its lower surface to fit within the inner side of the lip and to rest upon the shoulder referred to above to prevent crushing of a sealing gasket received between the bottom of the cover and the upper edge of the lip. Vent openings are formed through the lip to vent the manhole when the cover is in place. Spring clips on the cover engage an undercut shoulder on the rim to releasably retain the cover against removal from the rim.

Abstract: A fuel containment cover assembly comprising a fiberglass skirt with cast iron inserts molded into an integral unit. The inserts are located on the outer perimeter of the skirt and determine the flow of water from the cover to the ground. A pre-molded gasket extends about the interior perimeter of the cover. The gasket seats on the skirt assembly and seals the fuel containment device from the atmosphere. The cover is bolted to the fiberglass skirt and forms a drainage channel between the cover and the skirt.

Abstract: A vent valve for controlling the flow of vapor to or from the head space of a storage tank for fuel or other liquids includes a valve housing scalingly mounted in an opening through the top of the tank. A vertical vapor flow passage through the housing opens at its upper end at the exterior of the tank and at its lower end into the headspace of the tank. A spring biased valve head normally closes the lower end of the vapor flow passage to seal the headspace of the tank. A detachable and disposable pneumatic motor is mounted in a downwardly convergent frusto conical seat defined within the flow passage by webs integrally formed on the housing. The motor has a motor cylinder whose exterior surface is of a frusto conical configuration complementary to the seat and is wedged downwardly into the seat by mounting screws which pass through tabs formed on the cylinder into threaded bores in the top surfaces of the webs accessible from the upper end of the passage.

Abstract: A two stage float actuated shutoff valve for preventing overfilling of an underground storage tank has a first float actuated valve flapper movable to a closed position to block a major portion of the fuel inlet passage of the underground tank when the level of fuel in the tank rises to a first predetermined level. Closure of the first valve blocks a first portion of the flow passage while maintaining a second portion of the flow passage open to permit a reduced flow of fuel through the flow passage, thereby generating an observable water hammer effect signalling that the filling operation should be terminated. If the incoming flow is not terminated, the continued rise of the level of fuel in the tank will in time actuate a second float controlled valve to completely close the fuel inlet passage. The incoming fuel is supplied from a delivery truck tank, fuel flowing gravitationally from the truck tank through an operable shutoff valve on the tank, a delivery hose and a drop tube into the underground tank.

Abstract: A pressure relief or rollover valve is utilized on the tank of a fuel delivery truck to vent or relieve an abnormal internal pressure within the tank, such as that generated by an accidental deformation of the tank wall, while preventing spillage of fuel during the venting. A tubular valve housing is mounted in the top of the tank with a cover at the exterior of the tank releasably locked in sealed engagement with the upper end of a passage through the housing which opens at its lower end into the tank interior. A valve plate within the housing is biased downwardly to a valve closed position against an upwardly facing valve seat in the passage by springs engaged between the closed cover and the valve plate. A flexible bladder is sealed to the bottom of the cover to define an air chamber sealed from the passage, and openings through the cover vent this air chamber to atmosphere. A shield plate rests on the top of the cover to overlie the vent openings.

Abstract: A two stage float actuated shutoff valve for use in underground fuel storage tanks having a co-axial vapor recovery system utilizes a drop tube co-axially mounted within the storage tank fill pipe. Fuel flowing into the tank is passed through the drop tube which projects downwardly into the interior of the tank to a valve housing located at the lower end of the drop tube. Tubular floats slidably mounted on the drop tube within the tank independently operate pivoted flapper valves to a closed position within the valve housing, a lower float closing one valve flapper to block a major portion of the incoming fuel flow passage when the level of fuel in the storage tank reaches a predetermined first level and a second upper float closing a second flapper to completely close the flow passage when the level of fuel rises to a predetermined level about the first level. A float actuated locking arrangement for preventing inadvertent premature closing of either valve flapper is disclosed.

Abstract: A pneumatically actuated vent valve for venting the headspace of a fuel storage tank such as generally cylindrical a gasoline delivery truck includes a housing, sealingly mounted in the top of the tank and having a central passage opening at its lower end into the headspace of the tank and opening at its upper end, at the anterior of the tank into a hood. A pneumatic motor cylinder defining a piston chamber closed at its upper end is integrally formed with the housing coaxial to the central passage and a piston rod projecting downwardly from the piston chamber carries a valve head at its lower end disposed below the lower end of the housing. The valve head is normally biased upwardly into sealed engagement with a valve seal at the lower end of the central passage by three (or more) springs biased guide rods symmetrically disposed about the central passage wall.

Abstract: A float actuated valve for automatically shutting off the flow of fluid into a storage tank when the tank is filled to a predetermined level includes a pair of shutter plates movable transversely across the flow passage from an open position wherein the plates are retracted clear of opposite sides of the passage and a fully closed position in which the plates project into and cooperatively block the passage. A spring biased rotary trip plate underlying the shutter plates controls actuation of the shutter plates and may be held by first and second detents in rotative positions locating the shutter plates in the fully closed or a partially closed position. A lower float located within the tank releases the first detent to cause the trip plate to drive the shutter plates from the fully closed to the partially closed position when the level of fluid in the tank rises to a first level.

Abstract: An overfill and spillage protection device for capturing fuel spilled from a tank touch supply hose or the fill pipe of an underground fuel storage tank takes the form of a tubular reservoir having an axially flexible bellows shaped side wall. Forces induced by freezing or thawing of the ground in which the reservoir is embedded which would apply strain to the coupling between the reservoir and fill pipe are absorbed by the flexing action of the bellows shaped reservoir. A rigid tubular skirt slidably encloses the bellows portion to prevent concrete or dirt from packing into the concave regions of the bellows.

Abstract: A breakaway hose coupling includes axially separable housing sections maintained in coupled relationship with each other by a frangible coupling pin or set screw. Each housing section includes a valve controlled flow passage in which a spring biassed valve closes the flow passage when the housing sections are separated. Valve stems on the respective valves moves into axial abutment with each other as the housing sections are coupled to mutually hold the respective valves open when the housing sections are coupled.

Abstract: The improved process comprises placing in an open top, walled enclosure a pattern plate carrying the pattern for the core or mold part to be produced. The height of the pattern plate is adjustable relative to the tops of the walls of the enclosure so that when sand coated with a polymerizable resin is poured onto the top of the pattern the excess sand flows over the tops of the walls, covering the pattern with a mound of sand the slope of the walls of which is determined by the angle of least repose of the sand. A squeeze head having a surface corresponding to the surface of the pattern is now pressed downwardly onto the top of the pile of sand, to compact the sand about the pattern. While thus held by the squeeze head, material such as gas is passed from the bottom of the mold or core up through the now compacted sand, thus to polymerize the resin. The squeeze head is removed and the now cured, resin sand core or mold part is removed, ready for use in the usual way.