Cryogenic deflashing is a deflashing process that uses

cryogenic In physics, cryogenics is the production and behaviour of materials at very low temperatures. The 13th IIR International Congress of Refrigeration (held in Washington DC in 1971) endorsed a universal definition of “cryogenics” and “cr ...

temperatures to aid in the removal of

flash Flash, flashes, or FLASH may refer to: Arts, entertainment, and media Fictional aliases * Flash (DC Comics character), several DC Comics superheroes with super speed: ** Flash (Barry Allen) ** Flash (Jay Garrick) ** Wally West, the first Kid ...

cast Cast may refer to: Music * Cast (band), an English alternative rock band * Cast (Mexican band), a progressive Mexican rock band * The Cast, a Scottish musical duo: Mairi Campbell and Dave Francis * ''Cast'', a 2012 album by Trespassers William * ...

molded Molding (American English) or moulding (British and Commonwealth English; see spelling differences) is the process of manufacturing by shaping liquid or pliable raw material using a rigid frame called a mold or matrix. This itself may have ...

workpieces. These temperatures cause the flash to become stiff or brittle and to break away cleanly. Cryogenic deflashing is the preferred process when removing excess material from oddly shaped, custom molded products.

Process

Parts are loaded into a parts basket. A cryogen, such as

liquid nitrogen Liquid nitrogen—LN2—is nitrogen in a liquid state at low temperature. Liquid nitrogen has a boiling point of about . It is produced industrially by fractional distillation of liquid air. It is a colorless, low viscosity liquid that is wide ...

, is used to cool the workpieces; once cooled they are tumbled and

blasted ''Blasted'' is the first play by the British author Sarah Kane. It was first performed in 1995 at the Royal Court Theatre Upstairs in London. Synopsis The play is set in an expensive hotel room in Leeds. Ian, a foul-mouthed middle-aged tabloid ...

with media pellets, ranging size from . In some instances, cryogenic deflashing does not utilize a blasting action, relying instead only on the tumbling of the parts to remove flash on the outer edges.

Advantages

Cryogenic deflashing provides various advantages over manual deflashing and other traditional deflashing methods. * The process maintains part integrity and critical tolerances. * Since it is a batch process, the price per piece is far less as many more parts can be processed in a given amount of time. * Cryogenic deflashing extends mold life. Rather than replace or repair a mold (which typically involves downtime and high cost), the parts can be deflashed. This is typical of parts molded at the end of their

product lifetime Product lifetime or product lifespan is the time interval from when a product is sold to when it is discarded. Product lifetime is slightly different from service life because the latter consider only the effective time the product is used. It is ...

. * The process is computer controlled, therefore removing the human operator variable from the process. * The process offers consistent results from lot to lot. * Cryogenic deflashing is non-abrasive. * The cost per part is generally well below any alternative technique.

Applications

A wide range of molded materials can utilize cryogenic deflashing with proven results. These include: *

Silicone A silicone or polysiloxane is a polymer made up of siloxane (−R2Si−O−SiR2−, where R = organic group). They are typically colorless oils or rubber-like substances. Silicones are used in sealants, adhesives, lubricants, medicine, cooking ...

s *

Plastic Plastics are a wide range of synthetic or semi-synthetic materials that use polymers as a main ingredient. Their plasticity makes it possible for plastics to be moulded, extruded or pressed into solid objects of various shapes. This adaptab ...

s – (both thermoset & thermoplastic) *

Rubber Rubber, also called India rubber, latex, Amazonian rubber, ''caucho'', or ''caoutchouc'', as initially produced, consists of polymers of the organic compound isoprene, with minor impurities of other organic compounds. Thailand, Malaysia, and ...

s – (including neoprene & urethane) *

Liquid crystal polymer Liquid crystal polymers (LCPs) are polymers with the property of liquid crystal, usually containing aromatic rings as mesogens. Despite uncrosslinked LCPs, polymeric materials like liquid crystal elastomers (LCEs) and liquid crystal networks (L ...

(LCP) * Glass-filled nylons * Aluminum zinc die cast Examples of applications that use cryogenic deflashing include: *

O-ring An O-ring, also known as a packing or a toric joint, is a mechanical gasket in the shape of a torus; it is a loop of elastomer with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more par ...

s &

gasket Some seals and gaskets A gasket is a mechanical seal which fills the space between two or more mating surfaces, generally to prevent leakage from or into the joined objects while under compression. It is a deformable material that is used to c ...

s * Catheters and other in-vitro medical * Insulators and other electric / electronic * Valve stems, washers and fittings * Tubes and flexible boots * Face masks & goggles Today, many molding operations are using cryogenic deflashing instead of rebuilding or repairing molds on products that are approaching their end-of-life. It is often more prudent and economical to add a few cents of production cost for a part than invest in a new molding tool that can cost hundreds of thousands of dollars and has a limited service life due to declining production forecasts. In other cases, cryogenic deflashing has proven to be an enabling technology, permitting the economical manufacture of high quality, high precision parts fabricated with cutting edge materials and compounds.

References

External links

Nitrofreeze: In-depth information about how cryogenic deflashing works

A Cool Technology: Products Finishing Magazine, Matt Little; 4/1/2005
{{Iron and steel production Cryogenics Plastics industry Surface finishing