摘要:
The invention relates to a process for the production of boards of wood-based material from a mixture of lignocellulose- and/or cellulose-containing particles mixed with a binder, the mat or pressed stock being preheated by means of high-frequency (HF) or microwave (MW) energy and, after transfer into a single or multi-platen press or a continuously operating press, being pressed and cured by the application of pressure and heat. To increase the preheating temperature of the pressed stock and to reduce the pressing factor, the following process steps are provided: (a) the preheating in the core of the mat of pressed stock to ≧85° Celsius takes place after or during the precompaction by traveling wave microwave energy and its reflection in an interaction between emitted and reflected energy into the center of the mat of pressed stock, a. focusing of the radiation energy into the center cross section being performed at a large energy-introduction and energy-absorption angle &bgr;, for an increased heat gradient, and (b) the preheated mat of pressed stock enters the pressing region of the press with a moisture content which is 15% to 30% less than the conventionally-controlled moisture content.
摘要:
The invention relates to a process for the production of boards of wood-based material from a mixture of lignocellulose- and/or cellulose-containing particles mixed with a binder, the mat or pressed stock being preheated by means of high-frequency (HF) or microwave (MW) energy and, after transfer into a single or multi-platen press or a continuously operating press, being pressed and cured by the application of pressure and heat. To increase the preheating temperature of the pressed stock and to reduce the pressing factor, the following process steps are provided: (a) the preheating in the core of the mat of pressed stock to ≧85° Celsius takes place after or during the precompaction by traveling wave microwave energy and its reflection in an interaction between emitted and reflected energy into the center of the mat of pressed stock, a focusing of the radiation energy into the center cross section being performed at a large energy-introduction and energy-absorption angle &bgr;, for an increased heat gradient, and (b) the preheated mat of pressed stock enters the pressing region of the press with a moisture content which is 15% to 30% less than the conventionally-controlled moisture content.
摘要:
Veneer panels which are to be joined in a plurality of layers one above the other and one behind the other are assembled and glued to form an endless strand of veneer laminates. In the process, the veneer panels are first fed in through a glue-application machine which applies a layer of glue on a top side of the veneer panels onto a buffer belt. The veneer panels are then transferred from the buffer belt to a horizontally reversing feed belt which forms on a roller table a first veneer assembly comprising a plurality of veneer panels. The first veneer assembly is raised about its front end by an angle .alpha. into an oblique position so that veneer panels of a subsequent veneer assembly can be threaded into the first veneer assembly using the horizontally reversing feed belt. The first and subsequent veneer assemblies are thereby combined into a veneer-panel strand, and transferred to a continuously operating prepress and press.
摘要:
A method and apparatus for reducing the moisture content bound by capillarity in fiber cells of solid materials containing carbon. The material is ground and screened to form a loose sheet of the solid materials and/or sludges. The material is processed by screening and grinding methods for a plurality of hoppers for different grain sizes and grain size distributions. A thin layer of fines is spread as a first layer onto the spreading, feeding and filter belt, and a substantially thicker coarse material layer is formed as a second layer to form a sandwich of the material. The fines layer depth HF and coarse material depth HG of the sandwich correspond to the consistency and the proportion of the fines of the material. The sandwich formed is then carried by a belt into the pressure chamber of the filter press according to the dewatering cycle, while simultaneously the squeezed-out dry material is carried away.
摘要:
A continuously operating press for the production of particle boards, fiber boards and similar wood boards and plastic boards, has flexible endless steel belts which transmit the pressing pressure, pull the material to be pressed through the press, are guided over driving drums and reversing drums around an upper and a lower press beam and are supported with an adjustable press nip against press/heating platens on the press beams via rolling supporting elements which accompany their revolution and are guided with their axes transverse to the direction of belt running. The lower and/or the upper press/heating platen is vertically adjustable to set the press nip by a plurality of cylinder-piston arrangements arranged in rows transversely to the longitudinal axis of the press. The pressure pistons of the cylinder-piston arrangements each have a multi-surface support to give flexible multi-point introduction of force relative to the elastically deformable press/heating platens and spherical deformation of the press/heating platen over its length and width can be introduced by different forces in the cylinders across the width and/or the length by virtue of the multi-surface support of the cylinder-piston arrangements.
摘要:
A continuously operating press for the production of particle boards, fiber boards and similar wood boards and plastic boards comprises the combination of the following features: a) the press beams comprise individual beams of different lengths which can be connected to one another and are made up of web plates and ribs connecting the latter, the upper individual modules being suspended on two I-section girders which represent the length of the press and which take the pretensioning forces of the steel belts, while the lower press beam rests on two I-section girders anchored in the foundation; b) the two press beams are connected positively by tiebars that can be pivoted out and/or replaced quickly; and c) the cylinder-piston arrangements of one row are arranged between the tiebars and the heating platens together with their supporting crossmembers and supporting bodies or supporting strips in such a way that they can be introduced into and removed from the pressing zone after the release of some of the tiebars.
摘要:
A continuously operating press for production of particle boards, fiber boards or similar wood boards and plastic boards includes flexible endless steel belts which transmit pressing pressure and pull materials to be pressed through the press. The steel belts are guided via driving drums and reversing drums around an upper and a lower press beam and are supported with an adjustable press nip against upper and lower press/heating platens on the press beams via rolling supporting elements which accompany their revolution and are guided with their axes transverse to the running direction of the belt. The press ram for the press includes a plurality of individual beams, which are interconnected in an elastic and vertically adjustable manner and each individual beam has an elastically non-positive suspension of the upper press/heating platen for a longitudinal bending deformation at the press ram, and an elastically non-positive arrangement of the lower press/heating platen for a transverse bending deformation at the press ram. The press ram is regulated flexibly and hydromechanically.
摘要:
A continuous press is provided wherein the elastic forces are conducted centrically from the centering bolts into the vertical Y--Y axis and the longitudinal center of the guide chain. An accumulation of unilateral forces on the brackets of the guide chain is thereby avoided. The elastic forces, which are set up in the bearing bolts by the linear displacements of the rolling bars and are at times considerable, are thus conducted centrically into the guide sleeves and thus as a force centrically into the guide chain. The forces thus do not occur as an eccentric load on the guide chains and, consequently, are incapable of causing the destruction of the guide chains even with a relatively high load.
摘要:
Disclosed is an injection press for use in a transfer molding system for fiber reinforced thermo-setting resins, comprising an injection piston, an injection cylinder in which the injection piston moves, a feed bore which traverses the injection cylinder, a sprue orifice which leads into the mold, a telescoping sleeve which serves to seal off the feed bore when the piston travels toward the sprue orifice, wherein the injection piston seals the transfer bore at the end of the stroke near the sprue orifice, and wherein said feed bore is open when the piston is in a position a stroke length away from the sprue orifice.
摘要:
An injection press for forming a mass of plastic material to a desired shape comprising a die carrier plate for supporting a mold having an injection channel formed therein at a location corresponding substantially to the location of the optimum injection point, said die carrier plate having a plurality of bores therethrough arrayed in an X-Y coordinate field; a press plate parallel to said die carrier plate and having a plurality of bores therethrough aligned with the bores in said die carrier plate in said X-Y coordinate field; means interposed between said die carrier plate and said press plate for injecting plastic material into a mold; a closing rod extendable through a pair of aligned bores in said die carrier plate and said press plate, through said interposed injecting means and through the injection channel of a mold on said die carrier plate to force plastic material into the mold; said injection means and said closing rod being selectively positionable in said X-Y coordinate field so that the closing rod will pass through a selected pair of aligned bores in said die carrier plate and said press plate corresponding to the location of the injection channel of a mold on said die carrier plate.