Abstract: Embodiments of the present invention provide modular grid systems for use with aperture-forming devices. The modular grid system includes a plurality of modular grids, wherein each modular grid includes an outer frame, an outer partial ring coupled to the frame, and at least one inner partial ring coupled to the outer partial ring via at least one securable connection, wherein the outer partial ring and the at least one inner partial ring form arcs of greater than 180 degrees but less than 360 degrees. Each modular grid is coupled to an adjacent modular grid. In some embodiments, the outer frame comprises a removable bar. In some embodiments, the plurality of modular grids are oriented in the same direction. In some embodiments, the modular grid is configured to couple to an aperture-forming device, where the aperture-forming device has a diameter ranging from 2 to 6 inches.

Abstract: Devices and methods for twisting yarn may twist a strip of material, such as a paper strip, into a yarn, such as a paper yarn. Such devices and methods may involve positioning a pad formed from a roll of the material horizontally in a yarn twisting device, such that the strip of material is unwound and drawn from an outer circumference of the pad, but down through the center of the pad, and subsequently through a rotating yarn twister.

Abstract: Systems, apparatuses and methods for cutting and spooling paper are described. In one embodiment, a system for cutting a traveling web of paper that is being wound onto a first spool and transferring the paper web onto a second spool by feeding turn-up tape into a nip between the second spool and the paper web, comprises a transfer track for transporting the turn-up tape beneath the paper web and to a position adjacent to the nip, and a drive assembly capable of driving the turn-up tape along the transfer track toward the nip, wherein the drive is capable of being powered by manual power or motor power.

Abstract: Apparatuses and methods are provided for cutting a traveling web of paper that is being spooled on a full spool and transferring the paper web to spool on an empty spool by driving turn-up tape into a nip between the empty spool and the paper web. The apparatuses and methods provide a more problem free way of transferring a traveling paper web to an empty spool.

Abstract: A manhole lift insert positioning apparatus consisting of: (1) a threaded nut imbedded in a thermoplastic elastomer molding that fits snugly within a lift insert, and (2) a threaded wing bolt to engage the nut and expand the molding within the insert, thereby locking it in position and drawing the molding against the inside face of the concrete form, thus sealing the insert opening to avoid obstruction of that opening with concrete.

Abstract: A non-metallic ladder for use in a manhole in which permanent manhole steps have been installed and spaced relation from the top of the manhole to a position above the bottom and there being a pair of spaced side members on said ladder connected transversely by spaced steps to form corners at the top in which there are spaces to fit over a respective side members on the step. The spaces may be in the shape of a rectangular cross-section or other configuration. The ladder is "hung" from the step to resist dislodgment therefrom. There may be provided a wall bumper member at the bottom of the ladder to engage the inside wall of the manhole.

Abstract: In a method of producing metallic lead from a material including lead dioxide and/or metallic lead, including a step for dissolving the lead contained in the material and an electrolysis step for the cathodic deposition of the dissolved lead, the dissolving step is carried out with the use of an acid electrolyte in the presence of a redox couple which has a potential between its oxidised and reduced oxidation states such as to reduce the lead dioxide and/or oxidise the lead and which can be regenerated during the step for the electrochemical deposition of the dissolved lead. The method is used, in particular, for the production of lead from the active material of spent accumulators.

Abstract: A thermal gravity classifier in which various nonferrous scrap metals are classified and separated, using a single tank containing two layers of molten media. Shredded nonferrous scrap containing metal constituents such as aluminum, zinc, lead, and copper or the like are introduced to the top of the tank containing an upper layer of molten zinc, floating on a lower layer of molten lead. Metals such as aluminum, having a specific gravity less than zinc, by a screw conveyor approximately parallel with the top surface. Heavier metals and alloys such as copper or the like, having a melting point above the temperature within the tank, fall through the zinc layer and are conveyed from the tank by a separate screw conveyor extending up a diagonal wall of the tank. Metals such as lead and zinc, having a melting point lower than the temperature maintained within the tank, melt and gravitate to the appropriate molten layer in the tank.

Abstract: A system for receiving and crushing whole lead acid storage batteries, and for classifying the components of crushed batteries into lead oxide, lead metal, plastic case components, and rubber case components and other fragments. Whole batteries are crushed into component particles, and lead oxide from the batteries is placed in liquid suspension. The lead oxide is subsequently removed by three separate settling and classifying tanks. Lead metal is removed by a liquid upflow column separation. A flotation tank and surface skimming arrangement separates plastic case fragments from rubber fragments.