Abstract: The present invention relates to a seal device for a negative pressure calibrating unit in a extrusion line for producing profiled plastic sections, in particular pipes whereby the inner face of a seal rests against the circumference of the extruded profiled section in a formfitting manner and the seal is radially supported on the profiled section in order to apply a sealing force. It is the object of the invention to provide another similar device which is very easily constructed and can be produced inexpensively. This task is solved in that the seal is a porous and elastic foam body (13), the surfaces (17, 19) of that are exposed to the atmosphere are coated with an air-tight coating (21).

Abstract: A method and apparatus for moving along a tube extrusion line. An extruded tube is pushed through the extrusion line, by means of pressure generated by an extruder, to a withdrawal unit that takes over further driving of the tube. In a first-moving along phase, in which the tube has not yet passed a sealing of a calibration cooling unit relative to the atmosphere, the latter is under atmospheric pressure. In a second phase, in which the tube has passed the sealing, the calibration and cooling unit is placed under underpressure. In the first phase, the tube is supported either by internal overpressure or by a mechanical inner guide. A support cylinder extends axially from a casing head of the extruder and extends coaxially into a calibration sleeve in a first section of the calibration and cooling unit. A support plate is disposed between the casing head and an inlet of the calibration sleeve and provides external support for a tube exiting the casing head.

Abstract: A method and apparatus for moving along a tube extrusion line. An extruded tube is pushed through the extrusion line, by means of pressure generated by an extruder, to a withdrawal unit that takes over further driving of the tube. In a first-moving along phase, in which the tube has not yet passed a sealing of a calibration cooling unit relative to the atmosphere, the latter is under atmospheric pressure. In a second phase, in which the tube has passed the sealing, the calibration and cooling unit is placed under underpressure. In the first phase, the tube is supported either by internal overpressure or by a mechanical inner guide. A support cylinder extends axially from a casing head of the extruder and extends coaxially into a calibration sleeve in a first section of the calibration and cooling unit. A support plate is disposed between the casing head and an inlet of the calibration sleeve and provides external support for a tube exiting the casing head.

Abstract: Device for extruding hollow strands from thermoplastic material, with an extrusion die and a calibrating device, arranged between which is a mold chamber with an outer mold body for influencing the diameter of a hot, still moldable hollow strand emerging from an annular die of the extrusion die. The device is configured for extruding hollow strands of thermoplastic material and with which changing the wall thickness of the hollow strand emerging from the annular die is also possible. This is achieved by the mold chamber having an inner mold body, the inner and outer mold bodies being arranged coaxially in relation to the annular die and, by axial and/or radial adjustment in relation to each other, forming an annular gap between them for changing the cross section and/or the wall thickness of the hollow strand emerging from the annular die.

Abstract: Infinitely adjustable calibration sleeve for extruded plastic pipes includes an inlet head and two strap layers that intersect like a lattice grate and that are linked with each other at the crossing points. In that manner, the inlet head and the strap layers are adjustable to the pipe diameter, and the inlet head has radially adjustable overlapping segments in a radial plane distributed over the perimeter of the plastic pipe to be calibrated, and the segments mesh and have slots in their overlapping areas. Further, the faces of the segments are configured to lie on the plastic pipe to be calibrated, and the strap layers are linked to the segments flush with the faces. Such a calibration sleeve effectively seals the vacuum tank from the environment and prevents deformations of the entering, extruded plastic pipe.

Abstract: Infinitely adjustable calibration sleeve for extruded plastic pipes includes an inlet head and two strap layers that intersect like a lattice grate and that are linked with each other at the crossing points. In that manner, the inlet head and the strap layers are adjustable to the pipe diameter, and the inlet head has radially adjustable overlapping segments in a radial plane distributed over the perimeter of the plastic pipe to be calibrated, and the segments mesh and have slots in their overlapping areas. Further, the faces of the segments are configured to lie on the plastic pipe to be calibrated, and the strap layers are linked to the segments flush with the faces. Such a calibration sleeve effectively seals the vacuum tank from the environment and prevents deformations of the entering, extruded plastic pipe.

Abstract: The invention relates to a device for detecting faults in and/or measuring the wall thickness of continuously moving strips, sections or tubes of plastics, using ultrasonic signals. To this end a number of ultrasonic heads (A, B, C, D) with transmitters and receivers are disposed distributed over the width of the strip or section or the periphery of the tube. The signal, emitted by a transmitter of an ultrasonic measuring head (3) and reflected without scatter, is received by the receiver of said ultrasonic measuring head (3), while the scattered signals reflected on the tube, section or the like are received by the receivers of its adjacent ultrasonic measuring heads (A, B). The inclusion of the scattered and reflected signals in the measurement appreciably increases the measured area per measurement in comparison with using exclusively the signal directly reflected without scatter.

Abstract: The invention relates to corrosion proofing of current-carrying components of molten carbonate fuel cells. In particular, the invention relates to a current-carrying component for a molten carbonate fuel cell, particularly an anode current collector or bipolar plate, with a substrate made of stainless steel and with a corrosion proofing coating provided on the substrate to protect the component from the anode gas atmosphere and the molten electrolyte of the fuel cell.

Abstract: The invention relates to a control device for the mechanical or thermal adjustment of the nozzle (1) of an extruder for elongate products (2). In order to eliminate components for wall thickness fluctuations in the longitudinal direction of the elongate product (2) when determining the wall thickness of the elongate product (2) over its width or its periphery, a stationary ultrasonic measuring head (3) is provided in addition to a rotating or reversing ultrasonic measuring head (4). The measured values of the two measuring heads (3, 4) are so linked to one another in an evaluating unit (5) that it is possible to derive therefrom for the controller a correcting variable which leads to an adjustment of the nozzle (1) only if the wall thickness deviations discovered are due to an adjustment error at the nozzle (1).

Abstract: A method of making conference call connections in computer-controlled telephone exchanges includes combining voice signals of conference participants on a digital basis, forming a signal of a total of speaking levels of a given number of the most active participants, distributing the signal in an undamped manner, and suppressing voice signals of the inactive participants. A bit stream of the conference participants reaching a conference assembly through an incoming line is distributed to m adding processors having n channels each, and the PCM words are linearized with a code table and stored in level memories for each particular participant. A total of the linear values is formed, is added to individual participant evaluation totals and is stored in evaluation memories for each particular participant. The participant evaluation totals are transmitted to an evaluation processor which determines active channels by using a delayed mean value of the participant levels and transmits it to the adding processors.

Abstract: A method and a system for preparation of a highly concentrated and fine-grained suspension such as a coal-water slurry comprises feeding of coarse solid matter by a metering conveyor type weigher and of a carrier liquid and additives into a ball mill, in which the solid matter is ground and the suspension is formed. The particle size and distribution are analyzed and the viscosity is determined. The speed of the ball mill and the amounts of the carrier liquid and additives are adjusted during the continuous preparation process so that a suspension with constant characteristic features such as particle size and distribution, content of solid matter and viscosity is supplied into a pipeline.

Abstract: A method and apparatus for analyzing the solid matter content of a hydraulically conveyed stream in a conveyor pipeline to be monitored and controlled, comprising, taking of a representative sample of the material in the pipeline across the diameter of the pipeline, separating the solid matter particles in the sample and increasing the liquid proportion in the sample, depositing the separated particles on a filter surface, analyzing the distribution of size and shape of the particles on the filter and adjusting the conveyor accordingly to control a feed pressure in the pipeline and a liquid content of material in the pipeline. The analyzing step is performed by a microscope and a television camera which converts an optical image from the microscope into a signal readable by a computer which, in turn, through a microprocessor, controls a feed pump and liquid input valve.