Abstract: A liquid spill container and method of making and installing the same are provided wherein such container has a side wall comprised of at least two separate portions which are detachably fastened together. One of the portions defines the sole structure of the container which is adapted to be embedded in a fixed manner in an associated substrate to provide the sole support for the container in such substrate and the other of the portions being detachable from the one portion with the one portion embedded in the substrate to enable replacement of such other portion.

Abstract: A coupling apparatus specifically designed for an elbow of a fluid distribution system has a pair of rollers which are rotatable about first rotary axes which are movable with respect to the elbow and second rotary axes which move the first rotary axes in an arcuate path. The rollers selectively engage a locking groove of a second pipe section. The locking groove has arcuate portions with a radius equal to that of the rollers.The rollers are generally moved in unison but are permitted a small range of independent movement to insure locking of both rollers in the locking groove in the event of slight misalignments due to manufacturing tolerances.

Abstract: A pressure and vacuum relief vent has the stem of each of its pressure and vacuum valves, which are urged to their closed positions by weight, slidably mounted in a bushing of Teflon in a metallic seat ring so that corrosive build up does not occur on the bushing whereby each of the valves is responsive to the desired pressure differential due to weight. Each of the seat rings has a seat insert of Teflon locked in a groove in the seat ring with an epoxy seal between an outer inclined surface of the seat insert and an inner surface of the seat ring.

Abstract: A pressure vacuum vent has a body with means to vent an underground tank having vapors therein when the pressure within the tank exceeds a predetermined pressure and to allow ambient air pressure to enter the tank when the tank has a vacuum exceeding a predetermined vacuum. The body has a housing, which is open at its upper end, mounted thereon and extending upwardly therefrom with a cap mounted on top of the housing and spaced from the top of the housing to form passage means therebetween to allow vapor from the tank to flow upwardly therethrough. A cylindrical shaped shroud, which is preferably a single continuous member, is disposed in surrounding relation to the cap and the upper end of the housing to prevent any driven moisture from entering the passage means formed between the housing and the cap while still allowing vapor to flow only upwardly from the passage means through the shroud.

Abstract: An indicating gauge has dual floats to measure the levels of two liquids contained in the same tank. A separate measuring tape is controlled by each float to provide an indication of the liquid level through a single viewing window above the tank. In certain situations, a single float and measuring tape is used to provide an indication of the level of one liquid within the tank. A wiper is engageable with the viewing window to permit cleaning of the inside surface of the window.