Disclosed in the present application are: a pen-type structure for mixing and discharging a bio-ink or a hydrogel: and a bio-ink or hydrogel printing method using same. The pen-type structure comprises: a cylindrical first barrel for housing a first screw; a cylindrical second barrel for housing a second screw, which is longer than the first screw and has a structure parallel with the first screw; a controller connected to a gear of the first screw and a gear of the second screw so as to drive the first screw and the second screw; two or more supply units formed in the first barrier and supplying a bio-ink or hydrogel material into the first barrel; and a bio-ink or hydrogel discharge unit which extends from the end portion of the second barrel on the opposite side of the controller, and which discharges bio-ink or hydrogel.

The invention relates to a method for degrading (co)polymers in an extruder and an extruder suitable for performing said method.

An Extruder for providing a flow of viscoelastic material such as rubber is disclosed herein. The extruder includes several zones (A, P, H, S), each assigned to a particular rheological function and arranged axially from an upstream end to a downstream end of the extruder and having an endless screw of given diameter (D). In each of the zones, at least one helicoidal flight extends radially from a central shaft of the screw over a height (h.sub.1), in a direction and with a pitch which are defined for each of the zones, and which is rotationally driven about an axis (XX) in a barrel. The barrel is provided with various structures to further assist with the flow of the viscoelastic material

In order to provide a twin-screw extruder that can also be effectively used for a use, such as straining, since suppressing an increase in load power and the generation of heat of a material in a hopper unit and increasing pressure for extruding a material from a material outlet in a compression unit, the size of the lead angle of a screw blade at the position of the compression unit is set to be larger than the size of the lead angle of the screw blade at the position of the hopper unit 11 and the screw blade is disposed at the position of the compression unit so as to be wound two or more times.

The present invention relates to a process for devolatilising polymer-containing media such as, in particular, polymer melts, polymer solutions and dispersions and also devolatilisation apparatuses for carrying out the abovementioned process.

A kneading apparatus having a kneading unit made up of a plurality of segment parts detachably mounted on a shaft disposed in the barrel includes a first segment part having a first length L1 related to an outer diameter D, a second segment part having a second length L2 shorter than the first length L1, and a third segment part having a third length L3 longer than the first length L1; the first length L1 is [the outer diameter Da coefficient a]; the second length L2 is [the first length L1/a coefficient b]; the third length L3 is [the first length L1the coefficient b]; the third length L3 is [L1+L2]; and the kneading unit has a segment pattern made up of a plurality of segment parts and mounted on the shaft interchangeably with another segment pattern.

An extruder for processing hydrocarbon-containing material. The extruder includes a screw that is rotatably positioned in a auger barrel and a heating system positioned about at least a portion of the auger barrel that is designed to heat the hydrocarbon-containing material as the hydrocarbon-containing material moves through the auger barrel.

The invention relates to a four-flight screw element for a multishaft screw machine with screw shafts rotating in the same direction and at the same speed. The two screw elements according to the invention, which are located opposite each other directly adjacent on two directly adjacent screw shafts, practically clean each other in pairs. The invention also relates to the use of the screw element according to the invention in a multishaft screw machine and to a multishaft screw machine which is equipped with a pair of screw elements according to the invention, as well as to a method for the extrusion of plastic or viscoelastic masses using the screw element according to the invention.

The invention relates to a four-flight screw element for a multishaft screw machine with screw shafts rotating in the same direction and at the same speed. The two screw elements according to the invention, which are located opposite each other directly adjacent on two directly adjacent screw shafts, practically clean each other in pairs. The invention also relates to the use of the screw element according to the invention in a multishaft screw machine and to a multishaft screw machine which is equipped with a pair of screw elements according to the invention, as well as to a method for the extrusion of plastic or viscoelastic masses using the screw element according to the invention.

A multi-shaft extruder which has screw shafts which are rotatable in the same direction and at the same speed, and which has at least one gas venting opening, and which has, in the entry region of said at least one gas venting opening, screw elements with a particularly large pitch or screw elements which have an asymmetric screw profile or which are mounted eccentrically on the axis of rotation of the screw shaft. The invention also relates to the use of the extruder according to the invention for processing or manufacturing plastic materials, and to the use of the screw elements with a particularly large pitch or the use of screw elements which have an asymmetric screw profile or which are mounted eccentrically on the axis of rotation of the screw shaft, in the region of the gas venting opening of a multi-shaft extruder.