A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

The present invention relates to a process of producing a boom part from a sheet metal blank, in particular a process of producing a boom part having a bearing seat, in which the starting material is merely formed by bending. Thus, the production process is simplified. In addition, the present invention relates to a process of producing a boom that is closed at both ends by joining two boom parts produced by means of the process of the present invention. Furthermore, the present invention comprises boom parts and booms which are produced by means of one of the processes according to the present invention.

The present invention relates to an apparatus for increasing the flow rate in an engine pipe, and a processing method therefor and, more specifically, to an apparatus for increasing the flow rate in an engine pipe, the apparatus being provided in an engine pipe so as to define a circular flow of a gas by maximizing a circular flow length of the flowing gas, enabling the gas to flow circularly along an outer surface of a flow rate increasing tube body, preventing the occurrence of a vortex due to the collision of the gas flowing in the inside and the outside of the flow rate increasing tube body, and preventing the occurrence of noise and the like since the flow rate increasing tube body is firmly fixed to the pipe.

The present invention relates to an apparatus for increasing the flow rate in an engine pipe, and a processing method therefor and, more specifically, to an apparatus for increasing the flow rate in an engine pipe, the apparatus being provided in an engine pipe so as to define a circular flow of a gas by maximizing a circular flow length of the flowing gas, enabling the gas to flow circularly along an outer surface of a flow rate increasing tube body, preventing the occurrence of a vortex due to the collision of the gas flowing in the inside and the outside of the flow rate increasing tube body, and preventing the occurrence of noise and the like since the flow rate increasing tube body is firmly fixed to the pipe.

A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

A method of forming a duct section from a web of material includes the steps of forming a series of perforations in a web of material, the series of perforations defining an outline of one of a hole or notch in a finished duct section, forming a male lock bend and a female lock seam in first opposed edges of the web of material, forming flanges in second opposed edges of the web of material, removing the portion of material interior to the series of perforations to form the hole or notch, and bending the web of material to form the finished duct section.

A rigid sheet blank includes a first section configured to be bent about a first axis and a second section configured to be bent about a second axis. The first section has a peripheral edge and at least one tab extending from the peripheral edge. The at least one tab is bendable by hand. The second section defines at least one opening configured for receiving a respective one of the at least one tab during bending of the rigid sheet blank.

A plate type heat exchanger wherein the heat transfer assembly includes a plurality of heat transfer shells stacked in multiple layers.

The present invention relates to an apparatus for increasing the flow rate in an engine pipe, and a processing method therefor and, more specifically, to an apparatus for increasing the flow rate in an engine pipe, the apparatus being provided in an engine pipe so as to define a circular flow of a gas by maximizing a circular flow length of the flowing gas, enabling the gas to flow circularly along an outer surface of a flow rate increasing tube body, preventing the occurrence of a vortex due to the collision of the gas flowing in the inside and the outside of the flow rate increasing tube body, and preventing the occurrence of noise and the like since the flow rate increasing tube body is firmly fixed to the pipe.