START-UP AND OPERATING INSTRUCTIONS MANUAL STAMIXCO SMN INJECTION MOLDING STATIC MIXING NOZZLE

Installation and Operating Instructions Manual StaMixCo SMN Injection Molding Mixing Nozzle A) Start-Up and Operating Guidelines The following key points are critical for Start-Up and Operation of the SMN Static Mixing Nozzle. With over 4,000 installations world-wide, the mixing elements crushed in 11 instances (0.3% failure rate). In all instances, root-cause analysis revealed failure due to improper pre-injection heat up time. Please pay special attention to this manual. You and we don’t want your installation to become a failure statistic. 1) Maximum Operating Conditions A SMN Mixing Element...

The reason heat-up time increases with increasing mixer diameter is that the frozen polymer inside the mixer body is larger in diameter and must be melted by thermal conductivity alone. Polymer melts are insulators which mean they have very low thermal conductivity. The polymer layer thickness in the screw section is much thinner and thus takes less time to melt completely. Extreme caution is required for any location upstream of the static mixing nozzle where a solid “rod” of frozen polymer exists. These areas must be heated for complete melting prior to processing into the mixer section. Extreme...

oven or fluidized bed with afterburner be used to clean the mixing elements. a) If the mixing elements require cleaning, a purge compound is recommended. If a complete removal of polymer is required, a fluidized bed bath or a vacuum pyrolysis oven with afterburner is recommended. Maximum cleaning temperature should be 400 oC (750 oF) to retain the integrity of the mixing element material heat treatment. To clean the mixing elements, some very creative customers use an alternative cleaning method to avoid the high cost of a fluidized bed or pyrolysis oven with an afterburner. Against our recommendation,...

Figure #4: Plug Flow Step Response curve of SMN Mixing Elements show good plug flow self cleaning abilities as compared to an empty pipe. Figure #1: SMN Static Mixer homogenizes large temperature gradient created by the screw. Figure #5: Reduction of color concentrate additives of as much as 30% can be achieved with comparable part color density Figure #2: Empty pipe (top) provides no mixing. Eight (8) SMN Mixing Elements (bottom) create a high degree of mixing in a short length. Figure #3: Velocity profile in an empty pipe

B) SMN Injection Molding Mixing Element Construction and Orientation The Standard SMN Mixing Element Assembly consists of eight (8) mixing elements and is shown in Figure #6. The Alignment Pin & Slot arrangement on the mixing element outside diameter assures that the mixing elements are oriented 90o relative to each other as shown in Figure #7. With the Pin & Slot orientation system, the mixing elements can be assembled in only one way under the condition that no pins extend beyond the front and rear face of the mixing element assembly. The mixing element assembly is flow symmetrical and can...

The standard arrangement of the SMN Injection Molding Mixing Nozzle contains eight (8) high performance SMN mixing elements that homogenize the polymer melt as it enters the mold (see Fig. #2-bottom). The correct nozzle size is a function of flow rate and viscosity of the polymer processed. SMN mixing element dimensions and sizing are shown in Figure #8 and Table #1. Table #2 provides a quick budget size rating for different size mixing nozzles. Table #1: Key Sizing and Dimensional Parameters for SMN Mixing Elements showed in Figures #8.

D) Basic Housing Design and Installation of the Mixing Elements: Complete Nozzle Purchased from StaMixCo If a complete mixing nozzle with housing, heater bands and thermocouple probe was purchased from StaMixCo, the remainder of this Section D) may be skipped. Customer Supplies Nozzle Body to fit StaMixCo Mixing Elements If customer decides to purchase only the mixing element assembly from StaMixCo and manufacture their own nozzle, the following design considerations are important: Nozzle Body Construction: The two principle methods of installing SMN mixing elements into a nozzle are shown in...

Figure #9: Principle Methods of Installing SMN Mixing Elements into a Nozzle Body. Shown in top sketch is the “Tight Installation Method” . Shown in bottom sketch is the preferred “Floating Installation Method

The StaMixCo SMN Injection Molding Static Mixing Nozzle can pay for itself in a matter of weeks, if not days, depending on the size of your output. A customer case history payback period calculation is shown below. It is conservative in that the calculated is based only on savings realized in reduced colorant usage and the resulting cost savings. The below case history pay-back calculation makes no provisions for additional savings in reduced reject rates due to poor color mixing, rapid color changes, or other process benefits such as increased use of regrind, improved cycle time, lower part...

The general formulas used for pay-back calculations are shown in Table #5 and #6. Table #5: General formulas for pay-back calculations NOTES FOR YOUR PERSONAL INSTALLATION PAY-BACK CALCULATIONS:

A young company with over 50 years of employee accumulated experience in mixing technology. North & South America StaMixCo LLC 235 - 84th Street Brooklyn, NY 11209, USA Tel: (718) 748-4600 Fax: (718) 833-8827 E-mail: [email protected] Web site: www.stamixco.com Europe, Asia-Pacific, Africa StaMixCo Technology Ltd. Ebnetstrasse 8 CH-8474 Dinhard, Switzerland Tel: + 41 52 338 17 11 Fax: + 41 52 338 17 33 E-mail: [email protected] Web site: www.stamixco.com Local Distributor: Note: We believe the information contained in this Stat-up and Operating Instructions Manual to be correct. However, the information...