A nozzle assembly for an injection molding system has a nozzle adapter with one or more vent holes therein. A porous metal insert is provided in fluid communication with at least one of the vent holes. The porous metal insert is also in fluid communication with a flow channel through the nozzle assembly. As molten polymeric material advances through the flow channel from a barrel to a mold assembly, gases entrained in the molten polymeric material are vented through the porous metal insert and escape through the one or more vent holes. Pressurized air may be introduced through the vent holes, such as by one or more blow-back modules, to unclog pores of the one or more porous metal inserts between shots of the injection molding system.

A nozzle assembly for an injection molding system has a nozzle adapter with one or more vent holes therein. A porous metal insert is provided in fluid communication with at least one of the vent holes. The porous metal insert is also in fluid communication with a flow channel through the nozzle assembly. As molten polymeric material advances through the flow channel from a barrel to a mold assembly, gases entrained in the molten polymeric material are vented through the porous metal insert and escape through the one or more vent holes. Pressurized air may be introduced through the vent holes, such as by one or more blow-back modules, to unclog pores of the one or more porous metal inserts between shots of the injection molding system.

A nozzle assembly for an injection molding system has a nozzle adapter with one or more vent holes therein. A porous metal insert is provided in fluid communication with at least one of the vent holes. The porous metal insert is also in fluid communication with a flow channel through the nozzle assembly. As molten polymeric material advances through the flow channel from a barrel to a mold assembly, gases entrained in the molten polymeric material are vented through the porous metal insert and escape through the one or more vent holes. Pressurized air may be introduced through the vent holes, such as by one or more blow-back modules, to unclog pores of the one or more porous metal inserts between shots of the injection molding system.

A gas venting/introducing structure (1) including a body (2) and a porous portion (3) integrated with the body (2) having a plurality of gas venting/introducing paths (4) each in communication with the porous portion (3) at one end. The plurality of gas venting/introducing paths 4 are open to the outside of the body (2) at other ends thereof such that at least two gas venting/introducing paths (4) merge into a single path (5). The body (2) is made of a porous metal denser than the material of the porous portion (3). The gas venting/introducing paths (4) each has an inner wall (4a) defined by a smooth surface. The distance between a communication side (3a) of the porous portion (3) and an opposite side (3b) is on the order of 4 mm. A concavity is formed at the communication part between the gas venting/introducing paths (4) and the porous portion (3).

A nozzle assembly for an injection molding system has a nozzle adapter with one or more vent holes therein. A porous metal insert is provided in fluid communication with at least one of the vent holes. The porous metal insert is also in fluid communication with a flow channel through the nozzle assembly. As molten polymeric material advances through the flow channel from a barrel to a mold assembly, gases entrained in the molten polymeric material are vented through the porous metal insert and escape through the one or more vent holes. Pressurized air may be introduced through the vent holes, such as by one or more blow-back modules, to unclog pores of the one or more porous metal inserts between shots of the injection molding system.