Triple-flighted

Calcualtion of free cross-section surface of 4 1 single-, double- end triple-flighted twin screws " 7 (plus single-flighted twin screws assembled from eccentric discs)... 

Figure 2.13 explains the triple-flighted kneading disc and its effect according to R. Erdmenger [9]. 

Self-wiping screw elements with the maximum possible number of threads give the largest free cross-section (see Fig. 2.5, Chapter 2). Thus, triple-flighted elements should be used in the intake zone of twin screw extruders with Dc/Dj < 1.3, and double-flighted elements in the case of D0/D, > 1.3. An intake zone length of 4 to 6 D is generally adequate for effective product feed. 

Figure 5.17 Triple-flighted eccentric kneading blocks [5]...

Special forms of self-cleaning profiles are used in kneading elements. These include circular eccentric elements [4] and triple-flighted eccentric kneading elements [5]. The circular eccentric elements are circles with diameter A/2. The triple-flighted eccentric kneading... 

Figure 7.1 Triple-flighted pumping screw (left) and kneading discs (right)...

Figure 7.9 Efficiency of a triple-flighted screw during pressure generation in relation to the kinematic parameter of flow A...

Some geometries and elements from the early days of development are no longer used. In place of the small-volume, triple-flighted extruder with a diameter ratio D0/Dj of just 1.22, today s industries use large-volume double-flighted systems with a diameter ratio D0/Dj of 1.4 to almost 2. 

This is particularly important when combining elements with different numbers of flights. Thus single-flighted and triple-flighted elements are fitted with their profiles in parallel, while double-flighted elements are fitted offset at 90° relative to one another (Fig. 12.6). 

This is another Erdmenger patent self-cleaning, triple-flighted kneading discs. 

This patent contains a description of a screw mixer with eccentric, triple-flighted spirals. 

Claim is laid to a self-cleaning triple-flighted screw profile with two or three different tip widths. The barrel is cleaned only by the widest tip. 

This patent contains a description of a transition from a single-flighted to a triple-flighted and back to a single-flighted screw profile. The barrel is not cleaned in the triple-flighted region. 

Claim is laid in this patent for double-flighted and triple-flighted shoulder elements in a twin-screw extruder. A low product stress and lower energy input result. 

In this case, clearance strategies for double-flighted and triple- flighted conveying elements are described which lead to a maximum pump efficiency during pressure build-up. 

Moving from triple-flighted to double-flighted screw profiles... 

Generation 1 (from 1956) triple-flighted profile, fixed processing length, shafts installed above one another, fully enclosed... 

Figure 6.12 (a) Single-, (b) double-, and (c) triple-flighted screws (not self-wiping). 

The cross-sections of single-flighted screws are cam shaped, whereas those of double-flighted screws have roughly a double-tipped elliptical shape (Figure 6.13). Triple-flighted screws have three tips. 

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