Injection molding: Pressure-sensitive film helps keep parting lines even

Sensor Products Inc. (Madison, NJ) makes and markets Pressurex, which is similar in appearance to ordinary paper and is available in thicknesses of 4 or 8 mils. It is available in sheets or rolls that can be cut to size. After being clamped up and placed around the parting line of a mold, the mold can be closed. When placed between the two contacting surfaces, the film permanently changes color directly proportional to the actual pressure applied. A user then compares the resultant color intensity to a color correlation charts—akin to measuring acidity with Litmus paper. Pressurex reveals pressure from 2-43,200 PSI (0.14-3000 kg/cm²) and is available in eight different pressure ranges, with medium and high pressure most commonly used for injection molding.

“In injection molding, Pressurex confirms that parting lines are mating properly to prevent flash, and that the vents are open allowing for proper filling of the mold cavity,” according to John Bozzelli, owner of Injection Molding Solutions (Midland, MI), who uses Pressurex in his consulting and molder training services. (Ed.: Bozzelli also made MPW’s list of the industry’s most Notable Processors.) Sensor Products offers free samples; contact them at T: 1-973-884-1755, [email protected] or check out www.sensorprod.com/sample.—[email protected]