摘要:
A process for the manufacture of compacts, particularly cemented-carbide cutting blades, by compressing metallic powder and subsequently sintering the compacts wherein the compacts are formed in a powder press having a die-plate, an upper ram and at least one lower ram which are associated with a die-bore and are adapted to be actuated by a hydraulic press cylinder with the rams having associated thereto force-measuring devices and path-measuring devices to measure the compression forces during the ram feed motion up to the final positions, wherein the value of the energy to be applied by the upper ram is stored for a compact of predetermined geometry and dimensions and a predetermined material, that the overall energy to be applied by the upper and lower rams is further stored as a second value, that the feed motion of the upper ram is completed when the energy applied by the ram has reached the predetermined first value and the feed motion of the lower ram is effected depending on the application of the residual energy and is completed when the overall energy has reached the predetermined second value.
摘要:
A method for minimizing the spread of the maximum compression forces in compacting powder, specifically metallic powder, by means of a powder press which has a die-plate, an upper ram, and at least one lower ram which are associated with a die-bore and are respectively operable by a hydraulic press cylinder, and a charging shoe movable on the die-plate along a predetermined path for filling the die-bore with the powder, wherein the maximum compression force of at least the upper ram is measured upon arrival at a predetermined position, the charging shoe, the die-plate, the upper ram and/or lower ram are vibrated at a predetermined frequency and amplitude during the filling operation and/or at the beginning of the compression procedure and, in addition, the filling time or the course of charging shoe motion in time are predetermined, wherein the frequency distribution of the maximum compression force values is determined at intervals and the standard deviation is determined therefrom for the maximum compression force, the standard deviation is compared to a predetermined value, if desired, and the vibration parameters, the course of motion in time and/or the path of charging shoe travel are varied according to a predetermined program until the standard deviation has reached the predetermined value or a minimum.
摘要:
A hydraulic press for compressing metallic powder or the like to form compacts, comprising a die-plate, an upper ram, and at least one lower ram which interact with a die-bore and are operable each by a dual-action hydraulic press cylinder, whereby a limited dead path length is provided for the return stroke in the force path between the press cylinder and the upper ram in which the upper ram is not carried along, and that a separate pressure generator producing a variable pressure is arranged in parallel with the force path via which a compression force is produced on the upper ram during the dead path length.
摘要:
An arrangement of a die-plate of a hydraulic press to press powdered material into shape wherein an upper ram and a lower ram interact with a bore of the die-plate wherein the die-plate is supported via vertically arranged supporting standards which, along with upper supporting portions which are cantilevered towards the axis of the die-bore, define upwardly facing bearing areas located close to the die-bore for the die-plate.
摘要:
A process for compressing metallic powder into a compact in a powder press which has a die-plate, a hydraulically operated upper ram and at least one hydraulically operated lower ram, wherein the lower ram is set to vibrations while the die-plate is being filled with metallic powder.
摘要:
A process for compacting powdered material to form a compact of a predetermined thickness and having at least one lateral oblique surface by means of a bore in a die bolster for receiving the powdered material and an upper ram and a lower ram, which are operable by means of a hydraulic power-exerting device and are positionable by means of a control device with respect to the die bolster, comprising the following steps: The deformations of the die bolster are measured or calculated for various compacting forces and the correlating values are filed as a table in a memory with the deformations forces being determined from the difference of the compacting forces of the two rams, and Deformation is determined during the compaction procedure by applying the deformation force measured to the table and the feed length of the upper and lower rams is corrected depending on deformation.
摘要:
A process for the manufacture of compressed articles, particularly cemented-carbide cutting blade inserts, by compacting metallic powder and subsequently sintering the compact, particularly cemented-carbide reversible cutting blade inserts, which have a seating surface and at least one cutting edge extending approximately in parallel with the seating surface which is at a predetermined distance from the seating surface, by means of a press having a die-plate and a top ram and a bottom ram, comprising the steps of: Charging a predetermined volume of metallic powder into the die-plate bore with the bottom ram taking a predetermined charging position in the die-plate bore, Displacing the bottom ram and the top ram to predetermined first and second positions, Displacing the bottom ram and, if need be, the top ram more while simultaneously measuring the compressive force at least for the bottom ram with the shift of the bottom ram or top ram being effected along a predetermined curve desired for the compressive force, Terminating the charging movement of the bottom ram and, if need be, the top ram when a predetermined value is reached for the compressive force.
摘要:
A method for operating a rotary press, comprising a rotor rotatably driven about a vertical axis that has a die-plate and upper and lower rams which, while being guided vertically in guides of the rotor, interact with holes of dies in the die-plate wherein at least one compression station is provided and has an upper and a lower pressing roller past which the presser rams run along and by which they are moved towards the die-bore for the purpose of compacting the material in the die-hole, wherein the upper and lower rams are lifted subsequent to the compression procedure, causing the lower ram to eject a compact from the die and the compact to be stripped by a stripper in the direction of a discharge chute, characterized in that while an compact ejection procedure is under way the upper ram stands upright on top of the compact and is lifted therewith and the stripper seizes the compact laterally while the upper ram is still standing upright on top of the compact.
摘要:
A method for operating a rotary press, comprising a rotor rotatably driven about a vertical axis that has a die-plate and upper and lower rams which, while being guided vertically in guides of the rotor, interact with holes of dies in the die-plate wherein at least one compression station is provided and has an upper and a lower pressing roller past which the presser rams run along and by which they are moved towards the die-bore for the purpose of compacting the material in the die-hole, wherein the upper and lower rams are lifted subsequent to the compression procedure, causing the lower ram to eject a compact from the die and the compact to be stripped by a stripper in the direction of a discharge chute, characterized in that while an compact ejection procedure is under way the upper ram stands upright on top of the compact and is lifted therewith and the stripper seizes the compact laterally while the upper ram is still standing upright on top of the compact.
摘要:
A rotor for a tablet press including an upper-ram receptacle for the upper rams and a lower-ram guide for the lower rams of the tablet press, as well as a retainer plate having a series of die-bores which are oriented towards the upper and lower rams wherein the retainer plate is composed of at least two ring segments which are adapted to be mounted non-positively and/or positively to the body of the lower-ram guide by means of a fixing device.