PPS PET and PA parts nitrogen deburring machine
Cryogenic deflashing and deburring system is a process that employs cryogenic temperatures to remove flash on manufactured workpieces made of a wide range of plastics (and other materials) both thermoset and thermoplastic. Some examples of materials used include nylon, HD-PE, PPS, PET, polycarbonate, polypropylene, polyurethane, liquid crystal polymer, PA+GF, PC+GF, PEEK, and Acetal. Manufactured parts that have been successfully deburred include those made through injection molding, compression molding and extrusion molding.
What is “Flash.”
“Flash” is a raised edge attached to the workpiece. It is an unwanted piece of material and requires removal. Many medical devices and other precision components are included in deflashing applications. Deburring accounts for a significant amount of the costs of manufacturing. The cryogenic deflashing process causes the flash or burr to become stiff or brittle and break away leaving a clean edge. There are three types of burrs that can be formed in manufacturing operations and can be classified by the physical manner of formation: Poisson burr, roll-over burr and Tear burr.
■Poisson Burr
A Poisson burr results from the tendency of a material to bulge at the side when compressed until permanent deformation of the plastic occurs.
■Roll-over Burr
A roll-over burr is a burr that is more of a chip that is bent rather that sheared. The resulting burr is usually comparatively larger. The process even removes recessed burrs in blind and through holes.
■Tear Burr
A Tear burr is the result of material tearing from a work piece rather than shearing from it.
In the cryogenic deflashing process, parts are loaded into a basket. A cryogem such as liquid nitrogen is used to cool the workpieces. After they are cooled they are tumbled with pellets- often a polycarbonate media ranging in size from 0.006 to 0.080 inches (0.15mm to 2.03 mm.) Sometimes cryogenic deflashing does not rely on a blasting action but rather on the tumbling of the parts to remove flash from the outer edges. The process can even remove recessed burrs in blind and through holes. The process does not affect the surface finish or the geometry of the part. Edges are maintained without rounding or removal of extra material and only the unwanted burrs are removed.
Cryogenic Deflashing Systems Advantages
Cryogenic deflashing equipements provides advantages over manual deflashing.
■The process maintains part integrity and critical tolerances. As it is a bath process the price per piece is far less as many more parts can be processed at the same time.
■Cryogenic deflashing is non-abrasive.
■As the process is computer controlled, the human operator variable is removed from the process.
■Mold life is extended by the cryogenic deflashing process. Instead of making a new mold a company may choose to deburr a manufactured part cryogenically and achieve the same product quality very much as they would with a new mold for a period of time until maintenance is performed.
Pege’s Automatic Nitrogen Trimming Machine’s Features
■Greater productivity
■Large output in short time
■Better and consistent Finish
■Low Labour dependence
■Space Saving
■Low Media Consumption
■Wide variety of rubber compounds - NR to Silicon Rubber
■Low Nitrogen Usage
■Simple Electrical Controls
■High Efficiency Blast Wheel
■Safety Interlocks
■Simple and Very Low maintenance