An extrusion molding machine includes: a molding portion having one end and other end, the one end having a die, the other end being connected to an extrusion port of an extrusion portion, the molding portion also including a screen arranged therein. The molding portion includes: at least one first temperature controlling member between the screen and the die, the first temperature controlling member including a plurality of first zones divided in a circumferential direction. Temperatures of the plurality of first zones can be individually controlled.

An extrusion molding machine 1, including: an extruding portion 10 having a screw 11 and a barrel 12 capable of housing the screw; a molding portion 20 having one end and other end, the one end having a die 21, and the other end being connected to an extruding port 13 of the extruding portion 10; and a rectifier 30 arranged between the extruding portion 10 and the molding portion 20. A heat insulating member 40 is further arranged between the molding portion 20 and the rectifier 30.

Extrusion systems and methods with temperature control are disclosed. The ceramic batch material is flowed through a front section wherein the temperature of the batch material is locally adjusted through its perimeter at multiple locations. The temperature-adjusted ceramic batch material is then extruded through the extrusion die to form the extrudate. Temperatures of the extrudate at multiple outer surface locations having different azimuthal positions are measured. The temperature adjustment of the ceramic batch material is then controlled in a first feedback loop to control the shape of the extrudate based on the measured outer surface temperatures. The front section can also be cooled using a second control loop.

The invention relates to a method for mechanically treating clay (4), in particular for producing models, the clay (4) being heated by an extruder, extruded and applied to a surface (8), and to a corresponding device for mechanically treating clay (4), in particular for producing models. The invention is characterised in the device comprises an extruder (6) which is designed to heat and extrude clay (4) for applying to a surface (8).

An extrusion molding machine includes: a molding portion having one end and other end, the one end having a die, the other end being connected to an extrusion port of an extrusion portion, the molding portion also including a screen arranged therein. The molding portion includes: at least one first temperature controlling member between the screen and the die, the first temperature controlling member including a plurality of first zones divided in a circumferential direction. Temperatures of the plurality of first zones can be individually controlled.

A control strategy for producing high quality extrudates, including the steps of monitoring the temperature of a ceramic precursor batch by measuring the temperature of the batch material either directly or indirectly by measuring the temperature of a component of the extruder proximate to the die and transmitting the temperature data to an extrusion control system which comprises a master controller (106), at least one slave controller (110) and an optional supervisory controller. The supervisory controller determines batch temperature setpoint (102) in order to achieve the desired temperatures for extruding a certain type of batch material based on real time temperature inputs and stored parameters such as batch composition, process throughput, extruder cooling capacity, and the like. The master controller (106) receives batch temperature setpoint from the supervisory controller, and monitors batch temperature and in turn regulates at least one slave controller (110) which controls the flow of coolant (112) to portions of an extruder (114) in contact with the batch material.

A process for the calcination of raw gypsum in a heatable extruder, wherein the raw gypsum is feed into the extruder and heated to a temperature of from 150 C. to 350 C. to thereby convert the raw gypsum to calcined gypsum with a content of calcium hemihydrate of at least 50 wt.-%. By using a heatable extruder for the calcination, calcined gypsum with a high content of calcium sulphate hemihydrate and low residual amounts of the respective dihydrate and anhydrite can be obtained. The present invention further concerns a system, which is adapted to such preparation of calcined gypsum and includes an appropriate heatable extruder and the use of a heatable extruder for the calcination of raw gypsum.

An extruder, preferably for calcining and extruding raw gypsum, including a calcination zone and a mixing zone, wherein the extruder is optionally configured to capture and/or retain water liberated in the calcination zone, apparatuses and processes employing such extruders and respective uses.