Abstract: A method and an apparatus for detection of flaws in lumber is provided, in which the lumber is subjected to microwave radiation of equal intensity in turns simultaneously from two microwave radiation means in phase opposition and from an intermediate microwave radiation means and between the turns from none of said microwave radiation means. The microwave radiation transmitted through the lumber is measured and the level of the measured signals in pulse form is adjusted in such a way that the mean value of the pulse train equals a reference value. The level of the pulse train when no radiation is transmitted is adjusted to zero and the level of the pulses when said two microwave radiation means in phase opposition radiate is used as a measure of the size of the flaw in the lumber.

Abstract: Method for drying aqueous solid fuels, in which method the fuel is heated indirectly in a dryer by means of a heating medium heated in a boiler plant or the like and in which the steam formed in the dryer serves as a heating and transport medium. Oil or some other liquid having a boiling point higher than water is used as the indirect heating medium. Preferably oil is heated in the boiler plant up to the temperature of 300.degree. to 400.degree. C. at a 1 bar pressure. Heat surfaces of a lamella heat exchanger suitably serves as the heat transfer surfaces of the dryer.

Abstract: A method and apparatus for detecting grain direction in wood particularly in lumber by means of high frequency radio energy like microwave radiation. The grain direction in lumber can be detected so that knots will cause no significant error to the measuring result. The knots are detected by the method according to the invention in so far as they contain deviations of grain direction. The microwave radiation is either passed through or reflected from the piece of lumber. Radiation energy is transmitted with the aid of a transmitting antenna with a certain direction of polarization and a signal of grain direction is obtained by detecting microwave field by a receiving antenna whose direction of polarization plane forms an angle of 90.degree. with the direction of polarization plane of transmitting antenna.

Abstract: A press for removing liquid from a moving material web comprising two endless liquid impervious belts which form an extended press nip. At least one liquid pervious and/or absorbing belt passes through the nip together with the material web. The inner surface of one of the liquid impervious belts together with the pressure member forms a pressure compartment for exerting pressure onto the material web along its whole width in the nip with movable sealing strips at each end of the extended nip. The inner surface of the other liquid impervious belt slides along the slide surface of the support member.

Abstract: The invention relates to an apparatus for cutting lumber into any desired length. The cutting is carried out so that the piece of lumber is transported longitudinally, by means of a transverse conveyor, against a stop in either of two counter-check chains, which stop is connected to a carriage. The carriage can be moved in the longitudinal direction of the piece of lumber along guides by means of a servocylinder, and the position of the carriage can be suitably adjusted with respect to a circular saw next to it.

Abstract: Apparatus for washing fiber stock, comprising a substantially horizontally disposed rotating screen drum, means for supplying fiber stock to one end of said screen drum for passage along the screen surface through said screen drum, means for removing fiber stock from the other end of said screen drum, and a longitudinally extending liquid supply member fixedly mounted beneath the center axis of the screen drum, immersed in the fiber stock. The apparatus is provided with suction chambers and it acts as a screen with self-suction.

Abstract: A rotary feeder for simultaneous screening and discharging of material from the bottom part of a fluidized bed reactor. The rotary feeder is provided with a rotor having blades, between which pockets are formed. In the rotary feeder there is disposed an air inlet and an air outlet for accomplishing a flow of air through the pocket after it has moved over the inlet of the supply material.

Abstract: Press for removing water, wherein the material to be treated is led together with a wire which is pervious to water through a press nip zone formed by opposite surfaces. The press comprises compressible means for transporting the material to be treated. This means runs through the press nip and comprises several compression chambers which open out against the wire pervious to water. The compression chambers are preferably made so that they expand towards the water transmitting wire or felt, e.g. like a truncated pyramid.

Abstract: A method for orienting a log, supported by rotating means, which is to be fed into a saw or a similar device. The upper edge line of the log profile is surveyed by two cameras placed in such a symmetrical position above the log that a line from the camera to the log in the feed plane forms an olbique angle with the feed plane. Each camera records the edge line viewed by it and the log is brought by orienting movements in such a position that the images of the edge lines as viewed by the cameras are substantially mirror images of each other.

Abstract: A method for controlling the pH of the liquid circulation in a continuous prehydrolysis apparatus where a mineral acid or some other acid stronger than sulfurous acid is used as a hydrolysis agent and the material to be hydrolyzed is transferred, entrained in the liquids of a first and a second liquid circulation separated by a liquid exchanger, from a steaming vessel to a hydrolysis vessel by means of a transfer valve. Such an amount of alkaline sulfite or ammonium sulfite is added into the liquid of the first liquid circulation as is necessary to make the liquid alkaline or at least neutral.

Abstract: A method and an apparatus for sawing a piece of timber and particularly for edging a board. The piece of timber is brought to pass in its longitudinal direction through a measuring station and further, maintaining its position, to a sawing machine. The optimum width and sawing direction are determined by the measuring data obtained by means of measuring gates collected in the memory of a computer. The computer controls the sawing blades. The blades of the sawing machine are turned to take the desired sawing direction and are moved at an even speed in lateral direction during the sawing process. The apparatus comprises a conveyor for transferring the log of timber, a plurality of gates for measuring the optimum width and direction, a computer for collecting the data. The computer controls the blades so that during sawing, the sawing lines coincide with the edge lines of the calculated optimum board. The sawing machine is mounted on vibration dampers which act as springs.

Abstract: The disclosure describes a method and a device for pumping fiber suspensions of high consistency. Shear forces disrupting fiber flocs are induced near the front edge of the vanes of the impeller in a centrifugal pump which fluidize the fiber suspension hereby converting it into an easily pumpable state. This is effected by an inlet part having recesses and/or lobes in its inner surface in front of the impeller which cooperate with a rotor having an outer surface in which there are recesses and/or lobes disposed into the inlet part.

Abstract: A method and apparatus for feeding a fibre suspension onto the wire of a web former through a guiding device consisting of a plurality of guiding channels through which the fibre suspension flows parallelly and which are connected to a slice chamber leading to a slice and extending across the wire of the web former. A means for separating the dilute outer part of the jet of stock flowing in from every single flow channel is disposed downstream of the guiding device. The outer portion is deflected from the direction of flow of the thicker and more homogeneous core part and the latter is allowed to proceed up to the lip substantially maintaining its direction. Thus, a situation is reached, whereby considerably less local consistency variations occur in the lip flow across the head box. Preferably, this means is formed by a plate in which there are openings disposed coaxially with regard to the manifold tubes so that the diameter of the openings of the plate is smaller than that of the openings of the tubes.

Abstract: An arrangement for mounting lighting fixtures is provided. The lighting fixture or a plurality of lighting fixtures in a row are mounted on carriages movably disposed on a horizontal rail. The lighting fixtures can be moved from an operating position to a maintenance position by means of a first rope connected to the utmost carriages, whereby the movement of the utmost carriage to the maintenance position will push the carriages in front of it with regard to the direction of movement to a position in which all carriages are positioned close to each other. The lighting fixtures can be moved from a maintenance position to an operating position by means of a second rope being connected to each of the carriages, whereby movement of the utmost carriage to the operating position by means of the first rope will pull the carriages behind it with regard to the direction of movement to a position in which all carriages are positioned a distance apart from each other.

Abstract: A system for damping the pressure fluctuations in a paper machine headbox. The headbox applying the damping system comprises an equalizing chamber communicating with an air space, this equalizing chamber having an outlet/outlets for a channel/channels leading to the equalizing chamber as well as an inlet/inlets for a channel/channels leaving the equalizing chamber. The outlet chamber is disposed with regard to the inlet channel so, and the cross surfaces of the outlet and inlet channels have been dimensioned so that the jet of stock flowing out of the outlet and expanding divergently falls substantially inside the boundaries of the inlet.

Abstract: In a device for adjusting the flow quantity and drop size of black liquor to be injected into a soda digester, an outflow opening with an adjustable cross-sectional area, relatively rotatable coaxial outer and inner pipes, the outer pipe being provided with an end piece covering a part of the outer end of the outer pipe and the inner pipe being provided with a nozzle piece covering a part of the outer end of the inner pipe, the outflow opening being formed by an opening remaining outside the areas covered by the end piece and the nozzle piece.

Abstract: Gas is removed from a fibre suspension of high consistency by means of an apparatus having a rotor chamber and a rotor disposed for rotation in the rotor chamber. The rotor has blades adapted to fluidize the fibre suspension and to cause a centrally located core of gas surrounded by a cylindrical layer of fibre suspension to form. The rotor has a plate located in the portion of the rotor opposite to the inlet of the rotor chamber which has an opening or openings close to the rotor axis. The gas is removed from the rotor chamber through the openings in the plate to a gas discharge and the fibre suspension essentially free of gas is discharged through an outlet. The operation of the apparatus is controlled by maintaining the pressure difference between the inlet and the gas discharge at a predetermined level.

Abstract: A fluidized bed reactor e.g. for the burning of fuels of different calorific values. The bottom part of the combustion chamber is divided into an outer and an inner fluidization zone by a partition wall adjacent to the distributor plate. Heat transfer surfaces are disposed in the outer fluidization zone. Heat can be withdrawn from the outer fluidization zone which is activated when burning fuel having a high calorific value. When burning fuel of lower calorific value the outer fluidization zone is not operated. The inner fluidization zone will be in operation in both cases. The supply of fluidizing gas to the second fluidization zone is controlled in order to maintain predetermined conditions in this zone.