Abstract: An extruded D-shaped manifold machined from extruded tubing is generally D-shaped in cross-section, with the header being thicker than the tank. At least two longitudinal external ribs are formed on the header exterior, preferably positioned symmetrically relative to the longitudinal axis of the header. The external ribs provide additional strengthening of the header and act as stops to prevent the heat exchanger fins from contacting the tube/manifold joint (which can lead to leakage when the joint is brazed). The number of external ribs and their location depend on the size of the manifold and the precision required in positioning the heat exchanger tubes in the slots. The manifold can be extruded with lengthwise internal ribs extending along the interior sides of the tank to act as stops for the heat exchanger tubes.

Abstract: A sizing die for sizing a plurality of micro-extruded tubes has a side fence, a clamping fence in substantial parallel relation with and movable with respect to the side fence, a base fence adjacent to and perpendicular to ends of the side fence and the clamping fence, and a movable die platen for applying pressure to the top of the stack of tubes. The side and base fences preferably are fixed. The tubes to be sized are stacked on their sides against the side fence with their internal webs aligned throughout. The clamping fence and die platen are moved to be in mating engagement with the stack. Pressure is applied through the die platen against the top of the stack to compress the tubes to a desired thickness.

Abstract: An insert type extrusion die is presented for making small parts for use in electrical, automotive and other industries for manufacturing small component parts. The application of the invented die is illustrated for making multi-cavity flat aluminum tubes, which are used for small heat exchanger components, in automotive air-conditioners, condensors and radiators. The insert die is composed of a male die section having a protrusion part and a female die section having a die cavity is held detachably in a die holder. The male section is a roughly rectangular plate-shaped component, and has an integrally formed twist prevention region which is inserted into the receiver groove of the female section which is integrally formed thereon. The protrusion part defines the cavity shape of the multi-cavity flat tube, and the female section has the die cavity of the required cross sectional shape to define the outer shape of the tube.