A method of producing an injection molding tool for molding an article includes producing a replica of the article using at least one of an additive manufacturing process, a solid freeform fabrication process, or a computer numerically controlled (CNC) process. A support block is configured to receive at least a portion of the replica and support the replica with at least one of an outer peripheral surface of the replica or an inner peripheral surface of the replica positioned at a spaced distance from a peripheral surface of the support block. The replica is supported inside the support block at the spaced distance, a ceramic resin material is introduced into the spaced distance and cured to form a ceramic shell insert, the insert is removed from the cavity, and the insert is positioned within the support block to form a part of a mold tool adapted for installation in a standard plastic injection molding machine.

Modular tubing apparatuses for use in a shell-and-tube heat exchanger are described. Multiple apparatuses may be connected in series to form a high density, small tube diameter, long length tube apparatus assembly. Casting molds for forming modular tubing apparatuses are likewise described, including methods for casting such apparatuses.

A method of producing an injection molding tool for molding an article includes producing a replica of the article using at least one of an additive manufacturing process, a solid freeform fabrication process, or a computer numerically controlled (CNC) process. A support block is configured to receive at least a portion of the replica of the article and support the replica with at least one of an outer peripheral surface of the replica or an inner peripheral surface of the replica positioned at a spaced distance from a peripheral surface of the support block. The replica is supported inside the support block at the spaced distance, a ceramic resin material is introduced into the spaced distance and cured to form a ceramic shell insert, the insert is removed from the cavity and sintered, and the insert is positioned within the support block to form a part of a mold tool adapted for installation in a standard plastic injection molding machine.

A method of working an additively manufactured part includes applying a layer of wax to a part manufactured with an additive manufacturing process. Then a mold is formed over the layer of wax on the part. The wax is then removed from between the mold and the part. The part is then melted in the mold, and then the part is re-solidified in the mold. Finally, the mold is removed.

A method of working an additively manufactured part includes applying a layer of wax to a part manufactured with an additive manufacturing process. Then a mold is formed over the layer of wax on the part. The wax is then removed from between the mold and the part. The part is then melted in the mold, and then the part is re-solidified in the mold. Finally, the mold is removed.