Werner & Pfleiderer Gmbh

Wolfgang Worz

Gerhard Weihrich

Erwin Haring

Friedrich Schneider

Arno Knoll

Gerhard Pfaff

A die plate for the underwater granulation of thermoplastic material is formed with a base plate of an iron alloy, a hard annular cutting plate of titanium-carbide alloy, and an intermediate buffer layer containing nickel between the base plate and the cutting plate to equilibrate heat stresses due to different coefficient of thermal expansion of the base and the cutting plates. The intermediate layer is formed with a thickness of between 0.5 and 2 mm by hot-isostatic pressing a nickel-containing metal powder between the plates such that the intermediate layer is diffusion welded to the plates. Two nickel layers with an intermediate titanium-containing plate can also be formed. Also an ansenitic layer can be formed between the nickel layer and the base plate.

Process for producing a die plate for underwater granulation of plastic

A co-rotating twin-screw kneader has a casing which has two axially parallel bores, defined by the casing wall and which intersect with one another in a region to form gussets in said casing wall adjacent the intersecting region. Two axially parallel shafts which are arranged to be driven in the same direction of rotation are each arranged in a respective one of the bores and multi-flight kneading disks having crests associated with the casing wall are mounted in non-rotary manner on at least part of the length of each shaft. Each kneading disk on one shaft is associated with another disk on the other shaft in a plane perpendicular to the axes of the shafts and the disks are arranged to be moved past one another in a virtually clearance-free manner in the intersecting region of the bores. In order to achieve maximum flow rates and optimum melt homogeneity of material by using constructionally simple measures, the casing wall is dimensioned in such a way relative to the kneading disks, accompanied by the formation of a definite clearance between the casing wall and the crests on the kneading disk, but ##EQU1## in which Dg=diameter of the bores

Co-rotating twin-screw kneaders with kneading disks

An extractor for removing worm elements which are fastened for rotation on the worm shaft of a worm extruder wherein a frame formed of longitudinal and cross members has a locking device in one of the cross members for holding the worm elements and an opposed, displaceable, pneumatic piston-cylinder unit on another cross member. The piston-cylinder unit has a pressure piston which is extendable axially towards the worm shaft. Between the worm shaft and the piston-cylinder unit is a slide which is displaceable longitudinally and can be engaged by the piston of the piston-cylinder unit. The slide carries an impact device which is pneumatically actuatable and includes an impact shaft for engaging the worm shaft. The locking device includes two clamp jaws which are axially aligned with the impact shaft and the piston and engage the worm profile with an inner profile surface of identical type.

Method and extractor device for separating worm elements of an extruder

A screw housing with a wearing insert for a two-shafted screw machine wherein the wearing insert has two spaced parallel bores to accommodate screw shafts located with their mutually parallel longitudinal axes in the principal plane of symmetry of the wearing insert. These shafts are spaced apart so as to form saddles at the connecting point of the bores. The insert housing has an external cross-section which is substantially constant along its axial length and is arranged in a cavity of the screw housing having the same cross-section.

Growing community of inventors

Illingen, Germany

Wolfgang Worz