Abstract: An extrusion press for producing metal items by extruding a metal billet, said press comprising an extrusion die and a main cylinder including an extrusion punch adapted to be translated in two opposite directions, wherein the translation of said extrusion punch in a first extrusion direction results in a push against said billet and in the extrusion of said billet through said extrusion die, said press comprising a container and a movable punch holder crosspiece, both being translatable in two opposite directions parallel to the translation directions of said extrusion punch, wherein said container is adapted to be translated by means of at least a first dedicated cylinder including a first dedicated rod rigidly fastened to said container, and wherein said container is adapted to be moved close to said extrusion die by means of said dedicated first cylinder and rod so as to contain said billet.

Abstract: A system of pullers, in particular for extruding metals, the system comprising at least a first puller and a second puller, each equipped with gripping means adapted to engage and grip an end portion of a profile, in particular of an extruded profile exiting from an extrusion press, the system comprising a first guide and a second guide, where the at least two, first and second, pullers can be translated along the first and second guides, where the first guide is dedicated to the translation of both the at least two, first and second, pullers in a single first translation direction, and where the second guide is dedicated to the translation of both the at least two, first and second, pullers in a second translation direction opposite to the first translation direction.

Abstract: The present invent on relates to a press for the direct extrusion of metallic material. The press comprises a supporting structure, a container receiving the metallic material to be extruded, a container holder element and a plurality of adjustment devices to adjust the position of the container holder with respect to the supporting structure. The container holder element is movable along an extrusion direction by means of a plurality of pads slidable along corresponding guides integral with the supporting structure. The press comprises at least one motorized member operationally connected to at least one of the adjustment devices to determine a variation of the position of the container holder with respect to the supporting structure.

Abstract: The present invention relates to a press for the direct extrusion of metallic material, wherein the press comprises a supporting structure which defines an extrusion axis and a transverse direction orthogonal to said extrusion axis. The press further comprises an extrusion die and a die-holder drawer, in which said die is placed. Moving means are provided for moving said drawer along a transverse direction between a first position (P1), in which said die is aligned with said extrusion axis, and a second position in which, when reached, said die can be replaced. The press according to the invention further comprises a fixed supporting element which supports the drawer at least when it occupies the first position.

Abstract: The invention relates to a press for extruding metal material. The press comprises a hydraulic oil circuit for controlling one or more extrusion pistons movable within corresponding cylinders. Such a circuit comprises a fixed displacement, circulation pump operated by an electric motor with variable rotation speed. The hydraulic circuit comprises a main line and a branch line, along which a shutoff element is arranged. The hydraulic circuit comprises a hydraulic control unit comprising a pilot valve arranged along a pilot line provided with a first segment communicating with the main line and a second discharging segment. Said hydraulic unit is provided to move the shutoff element between an opening position and a closing position of the branch line according to the difference between the oil pressure upstream of the shutoff element and that in the first segment of said pilot line.

Abstract: A stretching machine for extruded profiles comprises a stretching head capable of translating along a predetermined direction (X) on a basement and actuation means for translationally actuating the stretching head with respect to the basement. The actuation means comprise a mechanical drive comprising at least one motor element, which is integral with one of said stretching head and said basement, and at least one driven element, operatively connected to the at least one motor element and integral with the other of said stretching head and said basement, and an electric motor operatively connected to the motor element of the mechanical drive.

Abstract: A system of pullers, in particular for extruding metals, said system comprising at least a first puller and a second puller, each equipped with gripping means adapted to engage and grip an end portion of a profile, in particular of an extruded profile exiting from an extrusion press, said system comprising a first guide and a second guide, where said at least two, first and second, pullers can be translated along said first and second guides, where said first guide is dedicated to the translation of both said at least two, first and second, pullers in a single first translation direction, and where said second guide is dedicated to the translation of both said at least two, first and second, pullers in a second translation direction opposite to said first translation direction.

Abstract: The invention relates to a press for extruding metal material. The press comprises a hydraulic oil circuit for controlling one or more extrusion pistons movable within corresponding cylinders. Such a circuit comprises a fixed displacement, circulation pump operated by an electric motor with variable rotation speed. The hydraulic circuit comprises a main line and a branch line, along which a shutoff element is arranged. The hydraulic circuit comprises a hydraulic control unit comprising a pilot valve arranged along a pilot line provided with a first segment communicating with the main line and a second discharging segment. Said hydraulic unit is provided to move the shutoff element between an opening position and a closing position of the branch line according to the difference between the oil pressure upstream of the shutoff element and that in the first segment of said pilot line.

Abstract: The present invention relates to a press for the direct extrusion of metallic material, wherein the press comprises a supporting structure which defines an extrusion axis and a transverse direction orthogonal to said extrusion axis. The press further comprises an extrusion die and a die-holder drawer, in which said die is placed. Moving means are provided for moving said drawer along a transverse direction between a first position (P1), in which said die is aligned with said extrusion axis, and a second position in which, when reached, said die can be replaced. The press according to the invention further comprises a fixed supporting element which supports the drawer at least when it occupies the first position.

Abstract: The present invent on relates to a press for the direct extrusion of metallic material. The press, comprises a supporting structure, a container receiving the metallic material to be extruded, a container holder element and a plurality of adjustment devices to adjust the position of the container holder with respect to the supporting structure. The container holder element is movable along an extrusion direction by means of a plurality of pads slidable along corresponding guides integral with the supporting structure. The press comprises at least one motorized member operationally connected to at least one of the adjustment devices to determine a variation of the position of the container holder with respect to the supporting structure.

Abstract: A method for the production of a separation microcolumn made in silicon wafer (11), for a chromatographic or gas-chromatographic system, is described. According to the method, a micro-trench (14) is first made in the silicon wafer. The micro-trench extends in depth in the silicon wafer (11) and along the entire path of the microcolumn. Then, a perfectly circular micro-channel (20), tangent to the upper surface of the silicon wafer (11), is obtained by an in-depth isotropic etching with reactive ions in the micro-trench (14). The microcolumn is functionalized by applying a stationary phase (SP) to the inner wall and finally, another wafer or a layer (17) of silicon or silicon oxide or polymeric material, that acts as a cap or cover, is applied onto the silicon wafer, thus closing the micro-channel. According to a variation, the functionalization is carried out after the micro-channel closure.

Abstract: A method for directly injecting a liquid sample into a capillary chromatography column, by which a liquid sample that includes the substance to be analyzed and the relative solvent is withdrawn from a vial with an automatic sampler having a syringe with a needle, and is then introduced into an insert, with which the injector of the chromatograph is provided, such that the terminal portion of the chromatography column is coaxially inserted into the needle to cause migration by capillarity of a part of the sample from the needle to the column. Excess sample overflowing from the needle at the moment in which the end of said column is inserted thereinto is received in a cavity, and the residence time of the end of the column within the needle is controlled.

Abstract: An apparatus for controlling the injection passage of on-column injector is disclosed. The apparatus includes a valve having at least one channel inside it and leading to the injection passage for the injection syringe needle. The channel is connected outside the injector to a source for carrier gas introduction, when the valve is open, or to the atmosphere, when the valve is closed, so as to allow a quick-type injection without the drawbacks of this injection type, as well as to have a solvent exhaust after injection.

Abstract: This invention relates to a method and a device for vaporization injection of a liquid sample in a gas chromatographic column housed in an oven comprising a direct on column injector suitable for injecting a liquid sample into the initial zone of a capillary column and capable of pneumatically sealing the injection port at the end of injection. Between the injector and the gas chromatographic column itself an uncoated capillary column length is provided in which vaporization of the injected sample occurs using heat from an oven housing said capillary column length, said oven being the same or separate from the oven containing said gas chromatographic column.

Abstract: An apparatus for feeding carrier gas at a constant rate to on-column injectors for capillary and micropacked gas-chromatographic columns. The apparatus includes a constant pressure gas delivering device in operation during the sample injection, and a constant rate gas delivering device in operation during the sample processing stage inside the column. The two devices are connected in parallel and a switch controls the alternative operation of the same.

Abstract: A method and device for sample injections into a gas chromatographic column, wherein, in order to achieve sample trapping and solvent effects, the injection zone and an initial portion of the column are kept at a low temperature and then a quick temperature change is performed at the end of said initial portion. The cooling action is preferably performed by a cooling fluid acting outside the injector and column, while said temperature change is obtained by a suitable thermoregulation of the oven wherein said gas chromatographic column is housed.