Abstract: The present invention relates to a method and apparatus for cooling. An exemplary apparatus includes an annular cooling ring operable for receiving a flow of a molten film bubble and expelling a flow of cooling gas, the annular cooling ring comprising a middle lip and an adjacent radially spaced apart outer lip, the middle lip having an extended length longer than the outer lip, a radially inner surface of the outer lip and a radially outer surface of the middle lip define a channel operable to allow the flow of cooling gas along the radially outer surface of the middle lip, wherein the middle lip is located radially intermediate the channel and the molten film bubble, and wherein the middle lip isolates the molten film bubble from the flow of cooling gas until the flow of cooling gas passes beyond the extended length of the middle lip.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Significant increases in production speeds are achieved with improved film quality over an increased range of tubular film sizes, down to a minimum size which occurs when operating at zero internal to molten film tube pressure.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas (i) in a path opposing the flow of the molten film tube toward a first exit gap and (ii) in a path with the flow of the molten film tube toward a second exit gap. A minimum gap between the divergent cooling interface and the molten film tube occurs at the first exit gap and/or the second exit gap. Advantageously, the divergent cooling interface is provided with one or more compound angles to maximize stability and cooling efficiency. Additionally, multiple cooling elements can preferably be arranged in a stackable configuration to achieve higher throughput rates.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process. Embodiments of the present disclosure provide a unidirectional cooling element having a unidirectional cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube. The unidirectional cooling element operably expels cooling gas in a path with the flow of the molten film tube toward an exit gap formed between the unidirectional cooling interface and the molten film tube. The minimum gap between the unidirectional cooling interface and the molten film tube occurs at the exit gap, and advantageously, the unidirectional cooling interface is provided with one or more compound angles to maximize stability and cooling efficiency.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Significant increases in production speeds are achieved with improved film quality over an increased range of tubular film sizes, down to a minimum size which occurs when operating at zero internal to molten film tube pressure.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas (i) in a path opposing the flow of the molten film tube toward a first exit gap and (ii) in a path with the flow of the molten film tube toward a second exit gap. A minimum gap between the divergent cooling interface and the molten film tube occurs at the first exit gap and/or the second exit gap. Advantageously, the divergent cooling interface is provided with one or more compound angles to maximize stability and cooling efficiency. Additionally, multiple cooling elements can preferably be arranged in a stackable configuration to achieve higher throughput rates.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process. Embodiments of the present disclosure provide a unidirectional cooling element having a unidirectional cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube. The unidirectional cooling element operably expels cooling gas in a path with the flow of the molten film tube toward an exit gap formed between the unidirectional cooling interface and the molten film tube. The minimum gap between the unidirectional cooling interface and the molten film tube occurs at the exit gap, and advantageously, the unidirectional cooling interface is provided with one or more compound angles to maximize stability and cooling efficiency.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Additionally, at least one cooling element is provided, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Significant increases in production speeds are achieved with improved film quality over an increased range of tubular film sizes, down to a minimum size which occurs when operating at zero internal to molten film tube pressure.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas (i) in a path opposing the flow of the molten film tube toward a first exit gap and (ii) in a path with the flow of the molten film tube toward a second exit gap. A minimum gap between the divergent cooling interface and the molten film tube occurs at the first exit gap and/or the second exit gap. Advantageously, the divergent cooling interface is provided with one or more compound angles to maximize stability and cooling efficiency. Additionally, multiple cooling elements can preferably be arranged in a stackable configuration to achieve higher throughput rates.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Additionally, at least one cooling element is provided, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process. Embodiments of the present disclosure provide a unidirectional cooling element having a unidirectional cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube. The unidirectional cooling element operably expels cooling gas in a path with the flow of the molten film tube toward an exit gap formed between the unidirectional cooling interface and the molten film tube. The minimum gap between the unidirectional cooling interface and the molten film tube occurs at the exit gap, and advantageously, the unidirectional cooling interface is provided with one or more compound angles to maximize stability and cooling efficiency.

Abstract: The present invention relates to an external cooling system for a molten film tube produced by a blown film tubular extrusion process, comprised of one or more enclosures with one or more respective cavities that directly receive a portion of cooling gas emanating from one or more associated cooling elements. Each enclosure includes a port containing a variable exhaust device and optional flow buffer, acting to maintain a pressure differential between the cavity and an adjacent inside volume of the molten film tube, adjustable to optimize molten film tube stability cooling element efficiency and spaced apart dimension between cooling elements. Additionally, at least one cooling element is provided, comprised of a divergent cooling element with a divergent cooling interface containing a cooling gas deflector spaced adjacent to the molten film tube and providing an expelled cooling gas.

Abstract: A gas assisted re-breathing device is provided for life support of individuals venturing into harsh environments, particularly the underwater environment, which results in reduced work of breathing. In the pressurized gas assisted re-breathing device, pressurized gas, actuated by the breathing pressure local to the mouthpiece, acts to move a flexible gas storage container on behalf of the individual and a loop seal valve is forcibly shut during assisted breathing, which seals the assisted breathing loop to prevent premature venting of breathing gas to the surrounding environment, unless the assisted breathing loop is full, whereupon the loop seal valve opens to allow excess breathing gas to escape into the surrounding environment through forcible exhalation by the individual through one or more conventional one way valves that prevent backflow from the surrounding environment back into the loop.

Abstract: A CO2 measuring device for use in a high humidity environment typically found in re-breathing apparatus, especially underwater re-breathing apparatus, that allows commonly available CO2 gas detectors to function properly and further provides for remote, continuous and/or quantitative sensing of CO2. Under normal conditions found inside re-breathers, a 100% relative humidity condensing environment exists that prevents the use of commercially available CO2 detectors which typically require relative humidity to be less than about 90 to 95% for proper operation. A venturi mixing device is disclosed that is driven by pressurized makeup gases routinely added into the re-breathing loop, acting to draw and mix with a portion of the moisture laden gas from the re-breather environment, creating a combined gas mixture with relative humidity well within the operating range of commercially available CO2 detectors.

Abstract: A constant mass oxygen addition device for use with a re-breathing apparatus is disclosed for use by individuals venturing into harsh environments, particularly the underwater environment, that remains unaffected by ambient pressure changes. This constant mass oxygen addition device comprises an intermediate chamber which is first pressurized with regulated pressure gas containing oxygen to a set value greater than ambient pressure and then subsequently vented to ambient pressure. This defines one constant mass dosing cycle. Multiple constant mass dosing cycles are repeated sequentially on a periodic basis sufficient to replace metabolic oxygen used by the individual and can be controlled either electronically or preferentially independent of electronics and linked to the respiratory rate of the diver.

Abstract: A CO2 measuring device for use in a high humidity environment typically found in re-breathing apparatus, especially underwater re-breathing apparatus, that allows commonly available CO2 gas detectors to function properly and further provides for remote, continuous and/or quantitative sensing of CO2. Under normal conditions found inside re-breathers, a 100% relative humidity condensing environment exists that prevents the use of commercially available CO2 detectors which typically require relative humidity to be less than about 90 to 95% for proper operation. A venturi mixing device is disclosed that is driven by pressurized makeup gases routinely added into the re-breathing loop, acting to draw and mix with a portion of the moisture laden gas from the re-breather environment, creating a combined gas mixture with relative humidity well within the operating range of commercially available CO2 detectors.

Abstract: A gas assisted re-breathing device is disclosed for life support of individuals venturing into harsh environments, particularly the underwater environment, which results in reduced work of breathing. Similar to prior art re-breathers, hoses connect a mouthpiece to direct the flow of breathing gas in a loop like fashion, passing in and out of a flexible gas storage container and a CO2 scrubbing device prior to re-breathing.

Abstract: A constant mass oxygen addition device for use with a re-breathing apparatus is disclosed for use by individuals venturing into harsh environments, particularly the underwater environment, that remains unaffected by ambient pressure changes. This constant mass oxygen addition device comprises an intermediate chamber which is first pressurized with regulated pressure gas containing oxygen to a set value greater than ambient pressure and then subsequently vented to ambient pressure. This defines one constant mass dosing cycle. Multiple constant mass dosing cycles are repeated sequentially on a periodic basis sufficient to replace metabolic oxygen used by the individual and can be controlled either electronically or preferentially independent of electronics and linked to the respiratory rate of the diver.

Abstract: An oscillating hauloff for blown film has a bearing structure positioned along the vertical process centerline. The bearing structure is separated into upper and lower sections to maintain a clear and open pathway for the web to pass across the process centerline. Passing the web across the process centerline allows the web to change directions before passing over a second turning bar, thus canceling any web wandering introduced by a first turning bar.