Plastics & Rubber

Cooling of hot spots in injection molds with CO₂

Our mold spot cooling technology using liquid carbon dioxide (CO₂) gives you advanced temperature control in hot spot areas of the mold that overheat due to lack of cooling. It is ideal for narrow areas that cannot be accessed with standard water-cooling channels, like core pins. Our PLASTINUM^® temperature control technology can access and cool these “hotspots”, uniformly cooling the whole part with up to 50% faster cycle times.

When the plastic melt is injected into the cavity, liquid CO_2, supplied from cylinders or bulk tanks, is injected through thin capillary tubes into defined cooling channels to quickly cool the part. The expansion to atmospheric pressure generates a mixture of CO₂ snow and gas, resulting in a highly effective local cooling action. The CO₂ removes heat from the mold and releases it into the atmosphere.
Benefits of mold spot cooling:

• High cooling rates
• Cooling of narrow mold sections with complex geometries
• Retrofit of existing molds with long cooling times possible
• No deposits or clogging in tempering ducts 

PLASTINUM Temp S

Highly accurate carbon dioxide metering for foam products

The highly accurate metering of liquid carbon dioxide (CO₂) against high and fluctuating counter pressures is crucial for the production of high-quality foam products with uniform cell structure. Due to its unique physical properties, CO₂ is more challenging to dose into extruders or other plastic machines compared to traditional liquid foaming agents. Customers can choose between two types of high-pressure metering units, depending on the application and requirements. Both types offer significant advantages compared to alternative dosing pumps. They provide high process stability and metering accuracy, even at high ambient temperatures, without the need for additional cooling devices. Gaseous, not flammable blowing agents like nitrogen can also be dosed. The PLASTINUM^® DSD 500 metering device is suitable for continuous or discontinuous processes and comes with several features and accessories. Additional benefits are an easy and quick start-up and the full ability for remote control. There are versions with a maximum of 30 kg/h and a maximum of 60 kg/h CO₂ flow rate available.

The PLASTINUM^® DSD 400 metering device is a cost-improved unit specially developed for extrusion foaming. It contains fewer standard features compared to the DSD 500, but additional features can be selected optionally. The maximum carbon dioxide flow rate is 30 kg/h.

Learn more about our partner, Maximator, with who we have developed products and technologies for extrusion and injection molding applications.

High-pressure nitrogen or carbon dioxide for cooling

Many different industrial applications require a steady supply of high-pressure liquid carbon dioxide (LIC) or high-pressure nitrogen. Typical applications in the plastics industry include extrusion foaming, gas injection molding, mold spot cooling, carbon dioxide (CO₂) snow cleaning in the plastics and other industries, thermal spraying and many more. The challenge lies in ensuring the required mass flow at the needed pressure to ensure the highest quality standards. Linde has developed the cost-effective PRESUS^® range of pressure boosters, designed for the highest standards of quality and reliability.

PRESUS^® C Pressure Booster:

 Comprises high-pressure boosting equipment for liquid CO₂ which supplies bubble-free, high-mass-flow at a constant high pressure to a variety of industrial processes.

PRESUS^® N Pressure Booster: 

Comprises high-pressure boosting equipment for nitrogen and argon, which can pressurize either liquid gas, nitrogen, or argon, which is afterward evaporated in a high-pressure vaporizer to supply high-pressure gas

Our environmentally friendly CRYOCLEAN^® cleaning options use carbon dioxide snow or pellets for cleaning. They include CRYOCLEAN^® Pellet Cleaning Technology, CRYOCLEAN^® Pellet Cleaning Technology, CRYOCLEAN^® Pellet Cleaning Technology.  Similar to sand blasting, dry ice particles are propelled by compressed air and shot on the contaminated surface.

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