Plastics Technology - Dedicated to improving Plastics Processing.
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Get more insights on tooling at: short.ptonline.com/toolingKH Learn more at PTonline.com KNOW HOW TOOLING ABOUT THE AUTHOR: Randy Kerkstra has been in the plastics industry for more than 26 years, occupied frequently with troubleshooting injection molding. He is currently a tooling manager for a large, multi-plant molding and manufacturing company. Contact: kbmoldingsolutions@gmail.com. Check out our product video (707) 838-6272 sales@microvu.com www.microvu.com EXCEL 501 Automated Machine 500x400x160mm $47,700 VERTEX 251 Automated Machine 250x160x160mm $33,100 SOL 161 Manual Machine 160x160x160mm $13,000 Prices include InSpec Metrology Software. Other models with sizes up to 2500x1600mm. AUTOMATE Measuring PLASTIC Parts? MICRO - VU'S FAMILY of MEASURING MACHINES is a FAST, ACCURATE, and EASY solution. less GPM. So with a 0.250-in. diam. hole, use a 0.187-in. high-flow tube. A 0.125-in. diam. hole with a 0.090 in. high-flow bubbler tube has greater area outside of the tube, at 0.0054 in.2, with the area of the ID of the tube being 0.0045 in. 2 . A 0.187-in. diam. hole with a 0.125-in. high-flow tube has area outside of the tube of 0.0153 in.2 and an ID area of 0.009 in.2. I have rarely seen bubbler hole sizes and tube diameters properly sized to achieve maximum GPM. It is very simple using basic math to figure the areas of the ID and the OD of the tube and the hole. Just take the radius2 x 3.14 to figure the areas of the tube ID, OD, and the hole. For the area outside of the tube you subtract the tube OD area from the area of the hole. On a tool running poly- propylene with Ampco beryllium- alloy slides that cored out a large area, the cycle times were running higher than desired because of how hot the slides were. The slides did have water in them but not inside the cavity detail because it was assumed that water was not an option. We were able to drill three 0.125- in. diam. holes into the detail using three high-flow, 0.090-in. bubbler tubes. In this case, bubbler heads were not an option, so we installed an insert inside the slide to allow bubblers to be used. The slides went from being so hot that they would burn your fingers to staying cold. Cycle time was reduced by approximately 20 sec. On another tool we were running glass-filled nylon on a round part with a 0.312-in. diam. hole through it that was approximately 5 in. long. A 0.156-in. hole with a 0.125-in. high-flow bubbler tube was used to cool the core. Even when running glass-filled nylon, the core stayed cool to the touch. So the results you can achieve with basic cooling methods and a little outside-the- box thinking can be amazing. If you look at the big picture and the payback, the excuse of plugged-up water lines from untreated water can really cost you a lot of money. You must consider the cross-sectional area between the tube and the water-line diameter so that you are using the proper tube size. @plastechmag 41 Plastics Technology T O O L I N G