Extruder

Classification of Extruders

Classification of ExtrudersRam Extruder

Classification of Extruders

Classification of ExtrudersCounter rotating screws

Non intermeshing Partial intermeshing Intermeshing

Classification of Extruders A) Single screw extruder, cross section of the feedzone. A1) Smooth (conventional), A2) GroovedSleeve

B) Pin barrel extruder

C) Co-Kneader, a Screw, b Kneading teeth, c Barrel

D) Single screw extruder with cavities in the barrel

E) Co-rotating twin screw extruder, intermeshing

F) Counter-rotating twin-screw extruder, intermeshing

G) Counter-rotating twin screw extruder, nonintermeshing

H) Planetary roller extruder, a Melting and feedsection, b planetary screws and sun screw

I)Cross section of a 4-screw degassing system

K) Gear pump

L) Plunger extruder, L1) Ram extrusion, L2)Hydrostatic extrusion: a Plunger, b Barrel, c Billet,d Extruded strand, e Hydraulic fluid

M) Single roll extruder, a Inlet, b Housing, c Roll, dAdjustable knife, e Die

N) Disk pack extruder. N1) Cross section(perpendicular), N2) Cross section (along theshaft), a Rotating disks, b Shaft, c Barrel, dChannel block

Classification of Extruders-Types of construction

Schematic of a single screw extruder

Machine parts for single screw extrusion

Hopper design

Machine parts for single screw extrusion

Good hopper Poor hopper

Geometry of feed opening in the feed throat

Machine parts for single screw extrusion

Vented extruder barrel with a two stage screw

Machine parts for single screw extrusion

Schematic of a single screw extruder-barrel heating or cooling

Machine parts for single screw extrusion

Machine parts for single screw extrusion

Screw zones main dimensions

Feed Zone(Solid conveying zone)

compression(plasticizing zone)Metering zoneMixing

part(optional)

Machine parts for single screw extrusion

Screw zones main dimensions

Feed Zone(Solid conveying zone)

compression(plasticizing zone)Metering zone

Mixing part

(optional)

A) single-flighted screw, B) B) double-flighted

screwb Channel width, D Barrel diameter ≈ Outer

screw diameter e,e* Flight width h Channel depth t Lead Flight clearance Helix angle

Machine parts for single screw extrusion

Dispersive and distributive mixing elements

Type Maddock

Type MaillefferBlister ring

Type Egan(with barreir flight)

Pine apple mixerType Saxton

Type DulmagePin mixing sections

Slotted screw Type Berstorff

Dispersive mixing elements Distributive mixing elements

Specialties of twin screw extrusion