An apparatus and method is described for providing a water impenetrable barrier between an underground duct and an access opening. The apparatus is particularly well suited to cover a secondary opening in a corrugated containment sump of an underground storage tank or the manway of a sanitary sewer, catch basin or other manhole system. The apparatus includes a cover, inflatable seal and a tank of compressed nitrogen to inflate the seal. When sealed to the access opening, the cover restricts the inflow of water or other debris into the interior of the underground duct and nitrogen may be released into the sealed access to reduce corrosion of components contained within the access.

A manhole cover system (10) for sealing manholes to minimize water infiltration includes a manhole cover (12) re-movably inserted into a manhole cover frame (14) having a compressible gasket (28) attached thereto. Manhole cover (12) includes a base (16) and a peripheral rim (18). Peripheral rim (18) includes a cover outer peripheral surface (20) and a horizontal cover seat (22). Manhole cover frame (14) includes a frame cover restraint wall (24) and a frame seat (26). During assembly, peripheral rim (18) is removably seated on frame seat (26) of manhole cover frame (14). Compressible gasket (28) forms a seal within a vertical clearance space (32) between cover outer peripheral surface (20) and frame cover restraint wall (24).

A manhole includes a device for safely closing and locking the manhole, which has a cylinder with centering pins that is attached to a slab and is rotatable with an operating key acting on the pins, and further includes an anti-burglary block, which in locked position is positioned inside the cylinder and hides and protects an anti-theft bolt positioned inside a hole, which crosses the entire anti-burglary block and has a larger diameter at the front and the same diameter as the anti-theft bolt in the back, so as to receive the anti-theft bolt in a threaded spot in the inner wall of the cylinder and enable placement of the anti-theft bolt in the body of the anti-burglary block when totally tightened into the threaded spot, wherein the end of the anti-theft bolt, in closed position, is housed in a locking hole on a circular support of the cover.

A sewer manhole cover includes a frame having an access aperture and a cover for covering the access aperture. A primary seal is generated when the cover is placed on the frame either by way of contact between the frame and cover or by way of a gasket received within a groove formed into one of the frame or cover, wherein the gasket is compressed between the frame and cover. A method is provided for generating a secondary seal between the frame and cover by applying an amount of a viscous compound to a circumferential surface of the frame or cover, wherein the secondary seal is formed when the cover compresses the compound when the cover is received within the frame.

An odor treatment device for a sewer that installs beneath a manhole cover. The device is formed from a circular shaped housing that fits within a manhole opening without modification. The housing is defined by sidewalls constructed and arranged to direct air an admixture of essential oils and a surfactant for treating of sewer odors. A baffle arrangement increases the velocity of air passing the admixture.

A removable and replaceable end cap that selectively lockingly engages a seat ring of a filter housing. The end cap may include a flange that compresses a gasket member between the end cap and the seat ring to form a fluid tight seal therebetween. The end cap may include cam locking grooves that may each receive insertion of a protrusion of the seat ring, and which are structured for at least rotational displacement about the received protrusion as the end cap is rotated between locked and unlocked positions relative to the seat ring. The end cap may also include an opening that accommodates the passage of a fluid to a filter element. The filter element, which may be coupled to the end cap, may be adapted to remove particulate or contaminate from the received fluid.

A laminous processed manway cover gasket includes an insert and a plurality of ePTFE layers of membranes wrapping the insert to result in isolation of the insert. In example, the isolation may result from a laminous, thermo-mechanical process that fuses together each ePTFE layer of membrane of the plurality of ePTFE layers of membranes.

A manhole base assembly and a method for making the same employ a non-cylindrical, low-volume concrete base that is fully lined to protect the concrete against chemical and physical attack while in service. This lined concrete manhole base assembly may be readily produced using a modular manhole form assembly which can be configured for a wide variety of geometrical configurations compatible with, e.g., varying pipe angles, elevations and sizes. The form assembly is configurable to provide any desired angle and elevation for the pipe apertures to interface with various underground systems, and can be formed on-site to facilitate compatibility with existing structures. The assembly provides for flexible, modular construction of a wide variety of lined manhole base assemblies at minimal cost, reduced concrete consumption and reduced operational complexity. The modular nature of the production form assembly also facilitates reduced inventory requirements when various manhole base assembly geometries are needed.

A manhole cover assembly comprises a base frame, the base frame comprising a base body and a base flange extending laterally outward from the base body. The assembly further comprises a top frame, the top frame comprising a top body disposed annularly about at least a portion of the base body, a top flange extending laterally outward from the top body, and a lip extending laterally inward from the top body.

A removable and replaceable end cap that selectively lockingly engages a seat ring of a filter housing. The end cap may include a flange that compresses a gasket member between the end cap and the seat ring to form a fluid tight seal therebetween. The end cap may include cam locking grooves that may each receive insertion of a protrusion of the seat ring, and which are structured for at least rotational displacement about the received protrusion as the end cap is rotated between locked and unlocked positions relative to the seat ring. The end cap may also include an opening that accommodates the passage of a fluid to a filter element. The filter element, which may be coupled to the end cap, may be adapted to remove particulate or contaminate from the received fluid.