Abstract: A drill rod opening device for sectional-rod drilling equipment, which opening device (5) comprises a coupling frame (9), which can be coupled to a drilling machine (1) of the drilling equipment and which is provided with a through hole (10) for a drill rod to be threaded into a drill rod shank of the drilling machine, and grasping device (13) mounted in the coupling frame. The grasping device are displaceable to a locking position, in which the grasping device extend into the hole in the coupling frame and, lock the rod to the coupling frame, and to a detaching position, in which the grasping device permit movement of the rod in relation to the coupling frame. The coupling frame is provided to be coupled to a front cover (4) of the drilling machine rotably but substantially axially undisplaceably in relation to the drill rod shank. The grasping device are provided to lock the drill rod in the locking position axially undisplaceably to the coupling frame.

Abstract: The invention relates to a nozzle for continuous separation of a representative sample from a duct-containing gas for its analysis. The nozzle has a pipe, intended to open into the sample-taking space, for continuous separation of the sample from a dust-containing gas and for directing the sample to be analyzed, and a second pipe for feeding water into the mouth of the sample-taking pipe in order to keep it clean and to mix the water with the gas sample.

Abstract: The present invention relates to a method and an apparatus for positioning a drilling apparatus with respect to a drilling plane formed by holes to be drilled in a rock in a tunnel. Light beams pointing in opposite directions are developed and fixed with respect to the drilling unit and are directed towards marks on the tunnel walls by adjusting the base of the apparatus in a horizontal plane.

Abstract: A pressure-medium driven percussion device including a body, a drill shank gliding axially in the body for transmitting percussions to a drill rod and a percussion piston moving in the body for directing percussions axially to the drill shank. The drill shank includes a lifting piston which moves in a lifting cylinder within the body. The body further includes a channel passing to the lifting cylinder for supplying and removing pressure medium into and out of the lifting cylinder and seals located between the body and the drill shank at both sides of the lifting cylinder. An equalizing channel is located between each seal and a corresponding choking slot. A valve connects the equalizing channels to the source of pressure medium when a channel passing to lifting cylinder is connected to a pressure medium container, and, correspondingly, to the pressure medium container when the channel passing to the lifting cylinder is connected to the source of pressure.

Abstract: A method for performing rock bolting, according to which a cementing agent is fed into a hole drilled into the rock, whereupon a bolt is fitted into the drill hole for supporting the rock. In order to permit use of a rapidly hardening cementing agent and mechanization of the bolting, a number of capsules (16) are fed to the bottom of the drill hole, which capsules contain a preferably two-component cementing agent which hardens rapidly when the components are mixed together, and a conventional cementing agent (12) hardening slowly and/or protecting the bolt against corrosion is fed into the remaining portion of the drill hole by means of a feeding pipe (5).

Abstract: The invention relates to a method of recovering chemicals from chloride-containing green liquor by precarbonating the green liquor by means of flue gases into hydrosulfide and soda, by removing hydrosulfide from the precarbonated solution in the form of hydrogen sulfide, by evaporation crystallizing the chloride- and soda-containing solution in order to separate the chloride salt from the alkaline solution. In order to reduce releases of hydrogen sulfide, the produced hydrogen sulfide is absorbed into a soda solution and/or an alkaline solution in order to produce a solution suitable for the preparation of white liquor, whereas the hydrogen sulfide which remains unabsorbed is returned to the precarbonation stage, in which the hydrogen sulfide is absorbed substantially completely. By means of the invention it is possible to achieve a closed cycle of chemicals without the chloride load of the system increasing, and at the same time the chloride is recovered and returned to the bleaching.

Abstract: A hydraulic piston cylinder device comprising a cylinder, a piston dividing the cylinder into two cylinder spaces (A and B), and valve members between the cylinder spaces and respective pressure medium pipes. The problem is to achieve a hydraulic piston cylinder device in which the pressure or tractive force of the cylinder is maintained even if the external pressure led into the cylinder would stop. To solve this problem, an elastic material is interposed between two piston parts, and is elastically compressible by the external pressure applied to the cylinder; and the valve members are coupled to each other so that when one of the valve members is closed the other cannot be closed.

Abstract: A cog-belt-driven power transmission device comprising a belt pulley having a cogging on the outer periphery and a belt having a corresponding cogging on the inner surface. In order to suppress the noise produced during rotation of the belt pulley one or more discharge channels for air entrapped between the coggings are made in the cogging of the belt pulley and/or the belt, said discharge channels connecting the cog gaps to the atmosphere.

Abstract: A method of controlling a grinding process in a pocket grinder in which a batch of wood in at least one pocket is pressed against a rotating grindstone by a pressure shoe displaceable in the pocket. At predetermined intervals an apparently produced amount of pulp is calculated at separate measuring points of the grinding stroke of the pressure shoe and the specific energy consumption calculated on the basis of this amount of pulp is compared to a target figure for the specific energy consumption. The batch grinding is adjusted depending on a deviation of the specific energy consumption from the target figure.

Abstract: Perforated sheet for a head box of a paper machine, the perforated sheet being provided with a number of parallel flow passages starting from a common front face. The perforated sheet is provided with a set of feeding ducts which can be connected to a source of flushing liquid and which is connected, by means of flushing ducts, to the front face of the perforated sheet. The perforated sheet preferably consists of several rod elements, each of which is provided with a flow passage and which have been assembled as parallel to each other, side by side and one above the other, into an integrated package.

Abstract: A working platform for a drilling apparatus for stoping shafts, said drilling apparatus comprising a base (3) displaceable in the direction of the shaft (1) and a supporting arm (5) pivotably supported on said base. On the supporting arm is mounted a drilling device (8). The working platform (10) is fastened to the supporting arm by means of an articulated means (11) which permits a pivoting of the working platform with respect to the supporting arm around two pivot axes (B, C) perpendicular to each other so that the working platform pivots synchronously along with the drilling device as the supporting arm is rotated for drilling holes in the shaft in the shape of a fan and is adjustable into a horizontal position irrespective of the rotary position of the supporting arm.

Abstract: A method of installing solder bolts in rock bolting, according to which method a bolt (11) is fed into a hole (12) drilled in the rock and is anchored in the hole during hardening of a soldering material (13). The bolt is bent during feeding into the hole in order to produce in the bolt at least one such bend (11a) that the bolt, when entirely inserted in the hole, is wedged in between opposite walls of the hole. A bolt feeding apparatus for carrying out the method includes a feed beam (8), a feeding device (9) supported by said beam for feeding a rock bolt into a drill hole, a displacing device for displacing the feeding device along the feed beam, and a rock support (6) for supporting the feed beam on the rock. The apparatus is provided with guiding means which, as the feeding device is moved along the feed beam, displace the feeding device away from a bolt feeding position coaxial with the axis of the drill hole and return the feeding device back to said feeding position.

Abstract: A method for drying a porous web, according to which method the wet web is passed onto at least one drying felt, the web and the drying felt are subjected to an air removal treatment, and the web and the drying felt are passed between two surface elements which are impermeable to liquid and form an extended press zone in which the web is subjected to a pressing effect from both sides. Before the press zone the wet web is heated to a temperature of at least nearly 100.degree. C., and in the press zone the drying felt is kept at a temperature lower than the temperature of the wet web, so that a lower pressure is produced in the drying felt, and the high temperature of the water in the web causes an explosive evaporation and transfer of water from the web into the felt.

Abstract: A method and an apparatus for drying a paper, or similar, web so that a wet web and a drying felt or wire are subjected to an air removal treatment, the web and the felt or wire freed of air are passed between moving surface elements having good heat conducting properties, said elements enclosing the web and the felt or wire along the whole width, the surface element contacting the web is heated in order to evaporate water contained in the web, and the surface element contacting the felt or wire is cooled in order to condense vapor emanating from the web into the felt or wire, and the felt or wire are separated from the dried web.

Abstract: An extended nip press for a paper machine for removing water from a wet paper, cardboard or that kind of a fibrous or porous web. The press comprises a rotatable press roll and two band rolls parallel to the press roll and an endless press band running around them which is pressed against the press roll for forming an extended press zone. The paper web to be dried is conveyed through the pressing zone with a dewatering felt. The press band consists of several separate parallel band strips, in the pressure zone. Each band strip is equipped with its own stretching device for individual regulation of the tension of the band strip.

Abstract: A vibrating apparatus e.g. for shaking the forming wire of a paper machine, comprising a body (1) and a drive shaft (2) rotatably mounted in the body. The drive shaft supports an eccentric bushing (3) displaceable along but nonrotatably fixed to said drive shaft. A reciprocating rod (9) positioned transversely with respect to the drive shaft is provided with a ring-shaped end (10) rotatably mounted around an outer mantle surface of said bushing stationary in the axial direction (D) of said bushing. The apparatus further comprises adjusting means (11-20) for displacing said bushing along the drive shaft in its axial direction in order to adjust the eccentricity between the drive shaft and the ring-shaped end of the reciprocating rod.

Abstract: An extended nip press for a paper machine for removing water from a wet fibrous or porous web. The press comprises two parallel, rotating press rolls which are pressed against each other and form therebetween a press nip through which a web to be dried passes together with at least one drier felt. At least one of the press rolls is provided with a hard support cylinder and a flexibly compressible shell layer surrounding said cylinder so that the press nip forms an extended press zone. In order to equalize the pressure and the temperature in the press zone, the shell layer is provided with a flexible layer formed by at least one liquid-filled cavity and a gas-filled cell disposed in the cavity, said flexible layer surrounding the support cylinder at least corresponding to the width of the web.

Abstract: An extended nip press for a paper machine for removing water from a wet paper, cardboard or similar fibrous or porous web. The press comprises a rotating press roll and at least one stationary loading shoe as well as a band impermeable to a medium and movable between said press roll and loading shoe. The loading shoe is provided with a sliding surface against which the press roll is pressed through the band for forming an extended press zone. A paper web to be dried is passed through the press zone together with a felt for receiving water. The band is made compressible, and in its surface facing the sliding surface are formed a plurality of separated recesses into which a lubricating medium is sprayed.

Abstract: The invention relates to a method for recovering sodium chemicals from green liquor by precarbonating green liquor by means of flue gases, by bringing a precarbonated solution into contact with a sodium bicarbonate solution and by stripping hydrogen sulphide from the so obtained reaction mixture by means of steam, for producing hydrogen sulphide gas and a sodium carbonate solution, which sodium carbonate solution is so pure, in relation to sodium sulphide that it can directly be led into the washing of the flue gases and into a carbonation stage, for producing the sodium bicarbonate solution.