The invention relates to covers for wastewater treatment lagoons, which are typically covered by expansive stretches of sheet-form, high density polyethylene (HDPE). The invention more particularly relates to improvements in attaching HDPE patches at distributed locations thereon, which patches provide locally increased thickness to the cover in service as seats for attachment of further attachments to the cover, such as for example and without limitation HDPE straps for retention of HDPE grout-filled ballast pipes, and so on.

There is provided a polymer fabrication method for forming 3-dimensional shapes from a sheet polymer blank (10) by machining at least one re-entrant, elongate groove forming a reduced thickness portion (25) permitting the blank to be folded and having opposed edges (12) at the surface, folding the blank about the groove to form at least a portion of the 3-dimensional shape, the re-entrant of the groove forming an elongate chamber (21) adjacent the reduced thickness portion and opening through an elongate gap (20) between the opposed edges, hot air welding the opposed edges across the gap with filler rod (22), and heating the reduced thickness portion to a selected thermo-reforming temperature via the chamber.

There is provided a polymer fabrication method for forming 3-dimensional shapes from a sheet polymer blank (10) by machining at least one re-entrant, elongate groove forming a reduced thickness portion (25) permitting the blank to be folded and having opposed edges (12) at the surface, folding the blank about the groove to form at least a portion of the 3-dimensional shape, the re-entrant of the groove forming an elongate chamber (21) adjacent the reduced thickness portion and opening through an elongate gap (20) between the opposed edges, hot air welding the opposed edges across the gap with filler rod (22), and heating the reduced thickness portion to a selected thermo-reforming temperature via the chamber.

Disclosed herein are exemplary embodiments of linings or liners (e.g., liners with corner reinforcement, etc.), methods of providing a liner or lining for a tank, and methods and apparatus for providing additional protection and/or reinforcement at the corners of a liner or lining. In an exemplary embodiment, a method generally includes positioning and attaching one or more corner attachments at one or more corners of a liner that are formed between the bottom and the one or more sides of the liner. The one or more corner attachments may be configured to provide additional protection and/or reinforcement at the one or more corners of the liner.

Disclosed herein are exemplary embodiments of linings or liners (e.g., liners with corner reinforcement, etc.), methods of providing a liner or lining for a tank, and methods and apparatus for providing additional protection and/or reinforcement at the corners of a liner or lining. In an exemplary embodiment, a method generally includes positioning and attaching one or more corner attachments at one or more corners of a liner that are formed between the bottom and the one or more sides of the liner. The one or more corner attachments may be configured to provide additional protection and/or reinforcement at the one or more corners of the liner.

The present invention relates to a method for producing a container which consists of a thermoplastic at least to some extent and comprises at least a first compartment element and at least a second compartment element joined to the first compartment element in a joining region by thermoplastic welding. The invention also relates to a plastic container which can be, and preferably is, produced according to said method.

The present disclosure relates to corner profiles and/or corner reinforcement for liners and linings that are suitable for use with tanks and other storage/containment vessels, such as process tanks, immersion tanks, indoor or outdoor containment pits, gravity feed conduits (e.g., concrete trench, canal, or drain, etc.) for transferring or conveying liquid, grain storage tanks or containers (e.g., dielectric or electrically non-conductive liners for grain storage, etc.), etc. The present disclosure also relates to tanks and other storage/containment vessels including liners and linings with corner profiles and/or corner reinforcement. Additionally, the present disclosure relates to methods, systems, and apparatus for providing corner profiles and/or corner reinforcement for liners and linings.

Described is a heated gaseous welder system and associated methods of welding plastic with the heated gaseous welder system. The heated gaseous welder system includes a welding tool and a welder control unit. The welder control unit includes a gaseous control system and a heater control system. The gaseous control system is configured to selectively supply a gas to the welding tool and control at least one characteristic of the gas supplied to the welding tool. The heater control system is configured to selectively control power supplied to the welding tool.

The present disclosure relates to corner profiles and/or corner reinforcement for liners and linings that are suitable for use with tanks and other storage/containment vessels, such as process tanks, immersion tanks, indoor or outdoor containment pits, gravity feed conduits (e.g., concrete trench, canal, or drain, etc.) for transferring or conveying liquid, grain storage tanks or containers (e.g., dielectric or electrically non-conductive liners for grain storage, etc.), etc. The present disclosure also relates to tanks and other storage/containment vessels including liners and linings with corner profiles and/or corner reinforcement. Additionally, the present disclosure relates to methods, systems, and apparatus for providing corner profiles and/or corner reinforcement for liners and linings.

The present invention relates to a method for producing a container which consists of a thermoplastic at least to some extent and comprises at least a first compartment element and at least a second compartment element joined to the first compartment element in a joining region by thermoplastic welding. The invention also relates to a plastic container which can be, and preferably is, produced according to said method.