Injection Molding Mixing Nozzle
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. . . mix it up SMN Injection Moulding Mixing Nozzle High Quality melt flow means …………. …………..…….better cash flow. INTRODUCTION We are living in a world of consumption. On a daily basis, Product Specialists and Injection Moulders must deal with many different tools, formulations, colours additives and mastebatches. Production rate, yield and high quality are Keys for Success. The StaMixCo SMN Injection Moulding Mixing Nozzle contains eight (8) very efficient static mixing elements that homogenize the polymer melt during injection. This homogenization is achieved by the continuous division of the molten polymer and its recombination when processed through the geometric structure of the mixing bars (Figure #1). are virtually indestructible. Pressure drop through the static mixing elements is low. Figure #1 shows the laminar flow behaviour of two resins (white and blue) when injected into an empty pipe (left) and through eight (8) SMN static mixing elements (right). These eight (8) SMN static mixing elements reduce polymer non-uniformity by a factor 6. Fig. #1: Mixing of blue and white epoxy resins. Empty tube (left) provides no mixing. Eight (8) SMN mixing elements (center and right) provide an almost perfect mix. The SMN mixing elements are extremely resistant due to their monolithic cast construction where the mixing bars are joined to each other and to the external ring wall via a single molten metal pour. They are made of heat treated high strength 17-4 PH stainless steel and Fig. #2: A Ready-to-Install StaMixCo SMN Injection Molding Mixing Nozzle with eight (8) mixing elements, nozzle body, heater bands and thermocouple.

MIXING QUALITY The optimum polymer melt quality for injection moulding is reached when at each location inside the polymer melt volume, a uniform distribution of colorant, additives and melt temperature exists. Using the StaMixCo SMN mixing elements, 80% of mixing (CoV = 0.2) is reached after eight elements and 97% (CoV = 0.03) after 16 elements as shown in Figure #3. Standard SMN Mixing Nozzle Contains Eight (S) Mixing Elements For Highly Critical Applications, 8 or More Mixing Elements are Sometimes Used Fig. #3: Evolution of mixing through the SMN Static Mixer Elements with Blue and...

NOZZLE SELECTION Fig. #9: Longitudinal cut through a complete SMN mixing nozzle The proper size of the SMN Mixing Nozzle is a function of the injection flow rate and viscosity of the polymer melt at the specific operating conditions. The SMN Mixing Nozzle (Figure #9) consists of a centre barrel section that holds the standard eight (8) mixing elements (licensee of Bayer AG, Germany). The left side threaded adaptor connects to the injection moulding machine. The right side adaptor with nozzle tip connects to the mould. The entire mixing nozzle is heated by heater bands whose temperature is...

START-UP AND OPERATING GUIDELINES (Condensed Version – for more information refer to the Installation & Operation brochure) Maximum Operating Conditions An SMN Mixing Element Assembly with eight (8) static mixing elements (Fig. #2) is designed for the following maximum operating conditions: o o a) 300 C (572 F) maximum continuous operating temperature b) 150 bar (2,175 psi) maximum allowable pressure drop Where these limits are expected to be exceeded, special mixing element assemblies are available. Installation Direction of Mixing Elements The Mixing elements may be installed with flow in...