A webless corrugated dual wall foundation drain which is constructed as a hollow rectangular tubular member with an inner corrugated wall formed of HDPE and an integral outer smooth wall formed of the same material. The outer smooth wall of the foundation drain is attached to and integrally formed with the corrugations of the inner corrugated wall through a coextrusion process, thereby significantly enhancing the vertical beam stiffness of the foundation drain and eliminating the need for an internal supporting web.

Methods and apparatus for making and using tools, for example concrete cutting blades. The tool includes a first layer and a second layer that are oppositely disposed. The first and second layers include working surfaces that support at least one working element when the working element is applied to a work piece. Additionally, an intermediate structure is included between the first and second layers. The intermediate structure can include a plurality of components extending in the area between the structural surfaces and the working surfaces.

A method and apparatus for manufacturing a duct bank comprising the steps of loading a frame with a series of templates, positioning the frame adjacent a pipe extruder, aligning a set of a plurality of holes with a die of the pipe extruder, extruding a pipe of a first length into the set of holes, repeating the steps of aligning and extruding for each set of holes, thereby forming the duct bank, banding the duct bank, and removing the duct bank from the frame.

A boreable multiduct assembly packaged for sale includes a receiver, a continuous outer conduit having a central lumen and multiple innerducts held freely in that lumen.

An apparatus and method to machine cavities in die blanks having little to no taper. The apparatus includes an elec trode tool (200) including intersecting walls coated with electrically insulating coating (258), an erosion face (204) comprising a cross section of the walls exposed through the electrically insulating coating, and a channel formed by the walls to supply electrolyte to the erosion face, the channels defined by interior surfaces of the walls and having an opening formed by edges of the erosion face. The method includes pulsed electrochemical machining a work piece with the electrode tool.

A hollow board cooling apparatus is for cooling a formed hollow board and includes first and second cooling devices, a coolant-circulating device, and a temperature-controlling unit. Each of the first and second cooling devices has a main body, a cooling channel extending through the main body to form inlet and outlet openings for passage of the hollow board, and a coolant channel formed in the main body. The coolant-circulating device introduces a coolant into the coolant channels via coolant inlets, and retrieves the coolant therefrom via coolant outlets. The temperature-controlling unit controls the coolant-circulating device to cool the coolant when the board temperature is higher than a reference temperature.

A honeycomb ceramic substrate, a method of making thereof, and a honeycomb extrusion die configured to extrude a honeycomb ceramic substrate from a batch of ceramic or ceramic-forming material is provided. The substrate may include a lattice of intersecting walls defining a honeycomb network of flow channels extending between an inlet end and an outlet end of the honeycomb substrate. Each flow channel may be defined by a plurality of channel walls of the intersecting walls with at least two of the plurality of channel walls including concave inner surfaces facing a center of the corresponding flow channel from central portions of the concave inner surfaces to concave corner portions facing the center of the corresponding flow channel.

A manufacturing method of a honeycomb structure forming die includes a linear slit forming step of forming, in a kneaded material discharging surface of a die substrate, a plurality of linear slits which are straight from one end to the other end on the kneaded material discharging surface, a slit sealing material disposing step of disposing a slit sealing material in parts of the plurality of linear slits, and a back hole forming step of forming back holes to introduce a kneaded material, in a kneaded material introducing surface of the die substrate which is present on a side opposite to the kneaded material discharging surface.

A concrete dowel placement system and methods for making the same. The system allows for accurate and easy substantially-parallel or parallel placement of slip dowels within sections of concrete so that adjacent sections of concrete may be allowed to undergo thermal expansion and contraction while remaining in a common plane without cracking or faulting. The system includes a coupler and a sheath. The sheath is configured to be slidably extensible over the coupler and may be held to the coupler by friction. Additionally, a method of constructing the concrete dowel placement system includes extruding material to form two tubes of different sizes. The tubes are then attached to each other, then material is extruded to form a sheath. Alternatively, construction may include extruding material to form a tube, then removing some of the material from the tube in order to form a coupler.

A concrete dowel placement system and methods for making the same. The system allows for accurate and easy substantially-parallel or parallel placement of slip dowels within sections of concrete so that adjacent sections of concrete may be allowed to undergo thermal expansion and contraction while remaining in a common plane without cracking or faulting. The system includes a coupler and a sheath. The sheath is configured to be slidably extensible over the coupler and may be held to the coupler by friction. Additionally, a method of constructing the concrete dowel placement system includes extruding material to form two tubes of different sizes. The tubes are then attached to each other, then material is extruded to form a sheath. Alternatively, construction may include extruding material to form a tube, then removing some of the material from the tube in order to form a coupler.