19-ScrewElements.gb...Last Update: /by:MK 19.1 Chapter: 19 Screw Elements: Types, Function, Identification Basics on screw elements Conveying elements Kneading elements Neutral elements Installation of the screw elements Numbering of the screw elements Principle of operation of the screw elements CWP Customer Training Seminar

19-ScrewElements.gb...Last Update: /by:MK 19.2 CWP Customer Training Seminar The Erdmenger patent "conditions of the sealing profile must be met" Along the screw connection there must be the same cross-section at all points Both shafts must have the same screw profile.

19-ScrewElements.gb...Last Update: /by:MK 19.3 D o = Outer screw diameter D i = Inner screw diameter a = Axle distance Diameter ratio: D a / D i (indicates available volume) Specific capacity: M d / a 3 (Indicates torque) DaDa DiDi a DoDo DiDi a Characteristic Dimensions

19-ScrewElements.gb...Last Update: /by:MK 19.4 Da Pitch (mm) x Da High pitchLow pitch Conveying Elements

19-ScrewElements.gb...Last Update: /by:MK 19.5 Extruder Rightflighted Elements Leftflighted Elements Conveying direction direction of the extruder flow against the in Conveying direction direction of the extruder flow Conveying Elements Right and Left-Hand Pitch

19-ScrewElements.gb...Last Update: /by:MK 19.6 Conveying Elements, Conveying,

19-ScrewElements.gb...Last Update: /by:MK (5) Stagger angle Spacer ring Kneading disc 5 Wide kneading discs Narrow kneading discs Kneading Blocks

19-ScrewElements.gb...Last Update: /by:MK 19.8 Kneading Blocks Kneading blocks comprise several kneading discs arranged behind one another. The staggering angle by standard is 45 or 90° The number and the width of the individual kneading discs is variable. The position of the kneading discs at the beginning and the end should be identical, for compatibility with other kneading blocks (i.e. to keep the modular concept).

19-ScrewElements.gb...Last Update: /by:MK 19.9 Kneading Elements

19-ScrewElements.gb...Last Update: /by:MK Element own conveying without Extruder Rightflighted ElementsLeftflighted ElementsNeutral elements Conveying direction of extruder flow in the direction against direction Conveying direction of extruder flow Kneading Elements

19-ScrewElements.gb...Last Update: /by:MK Conveying and Kneading Elements, Left-Hand Pitch

19-ScrewElements.gb...Last Update: /by:MK Quiz Q: Which connection between the screw element and the screw shaft is shown? A: Refer 18.1 ff

19-ScrewElements.gb...Last Update: /by:MK Installation of Screw Elements

19-ScrewElements.gb...Last Update: /by:MK Installation of Screw Set Elements

19-ScrewElements.gb...Last Update: /by:MK flight elements2- flight elements3- flight elements Faces always parallelly Faces always offset by 90° Installation of Screw Set Elements Faces always parallelly

19-ScrewElements.gb...Last Update: /by:MK Profile Transitions Profile AProfile B Transition piece required -for profile joint (profile A to B -if the faces of identical profiles are offset (kneading block) Profile AProfile B Risk of breakage

19-ScrewElements.gb...Last Update: /by:MK Transition Elements For technical fluidic reasons, but also to prevent mutual contact of the screws, a transition piece is necessary between different profile cross-sections, similar to that required for kneading blocks. Spacer rings, with the same outside diameter as the inside diameter of the screw elements, can be used instead of transition elements in some cases.

19-ScrewElements.gb...Last Update: /by:MK Part Numbers on the Screw Elements No. of flights, direction channel, right Special version 2-channel, right 3-channel, right 1-channel, left 2-channel, left 3-channel, left ° 45° 60° 90° Kn.block : No. of discs Offset angle Pitch of conveying elements -/ Connection Screw Elemnet/Shaft 00, 01, 02 66, 67, 68 24, 25, 34 Feather key (0°) 6-key Involute SC Other numbers available for special geometries. 34 MEGA-Compounder Profile Screw element with sealing profile Kneading block Element length Screw diameter Material Nitriding steel Cr steel CPR-HSS steel Wear and/or corrosion protected elements of composite materials 37 CPR - composite material

19-ScrewElements.gb...Last Update: /by:MK Recognising Screw Element Materials Corrosion and wear-resistant HIP - composite Standard wear protection HIP - composite Nitriding steel nitrified Material no Material Specif.

19-ScrewElements.gb...Last Update: /by:MK Recognising Screw Element Materials Former standard wear protection HIP - composite Soft martensitic hardened Cr-Ni steel with applied crest welding Material no.Material Specif.

19-ScrewElements.gb...Last Update: /by:MK Kneading (dispersing) elements Kneading- Mixing (homogenising) elements Mixing Conveying elements Conveying Pressure Barrier Process Section elements Left-handed Principle of Operation of the Screw Elements

19-ScrewElements.gb...Last Update: /by:MK Conveying Mechanism

19-ScrewElements.gb...Last Update: /by:MK Principle of Operation of the Conveying Elements Type of elementFree cross-section Conveying efficiency 1-channel elements Standard elements "Undercut" elements

19-ScrewElements.gb...Last Update: /by:MK Filling Level of Conveying Elements With decreasing pitch the free volume in the screw channel decreases, i.e. the filling level increases.

19-ScrewElements.gb...Last Update: /by:MK Filling Level of Conveying Elements Normally conveying elements with a high pitch are installed below the feed inlet. The bulk material is compressed by the reduction in pitch in a downstream direction, i.e. as a result of reduction of the channel volume.

19-ScrewElements.gb...Last Update: /by:MK Type of element Mixing effect Conveying effect Kneading effect (shearing) neutral standard X° Type of element Mixing effect Conveying effect Kneading effect (shearing) wide vs. narrow: standard vs. neutral: Merit comparison for different Kneading Blocks

19-ScrewElements.gb...Last Update: /by:MK Left-Handed Elements product flow p [bar]

19-ScrewElements.gb...Last Update: /by:MK Left-Handed Elements

19-ScrewElements.gb...Last Update: /by:MK Principle of Operation of the Left-Handed Elements Type of element Build-up effect Right-handed screw element with low pitch Neutral kneader block Left-handed kneader block Left-handed screw element

19-ScrewElements.gb...Last Update: /by:MK Residence Time Time (sec) Tracer with left and righthand KB with righthand kneading block without kneading block

19-ScrewElements.gb...Last Update: /by:MK Recognising Screw Element Materials Q: Which features can be used to recognise the material of a screw element if the material code on the faces of the screw elements has become illegible with cleaning? A: refer Chapter 19, slide 18ff