Abstract: A method for constructing tambour slats using a system of router bits. The router bit system can include at least two router bits, one of which may have a semi-spherical nose cutting surface and a concave ‘S’ shaped ogee cutting surface; and the other of which may have a ‘S’ shaped ogee cutting surface and a concave quarter round cutting surface. The method for constructing a tambour slat can include milling a groove in a strip of material. The strip of material with a groove may then be milled to form a tongue and a neck portion that may slide into a groove milled in another strip of material. The milling operations may be performed by a router fitted with the router bits from the router bit system. By using the router bit system, each strip of material may yield up to two tambour slats.

Abstract: An internal wheel suspension and shock absorbing system, including a hub with radially extending rods or blades, cooperating with sector braces, fixedly mounted by hubs to the interior of the rim for a wheel. The rods and blades secure onto a hub, that mounts onto the vehicle axle, for rotation. When a force is encountered, the forces are absorbed by the blades that extend either through or cooperate with the braces and biasing springs, which are adjustable, that bias against the outer radial edges of the blades or telescoping rods, and absorb the vector forces generated from any impact.

Abstract: A pneumatic tire having at least two belt plies provided radially outwardly of a carcass ply in the tread. A belt cover ply is disposed radially outwardly of the at least two belt plies. The belt cover ply has reinforcing cords that extend in the circumferential direction of the tire and is covered with coating rubber. The belt cover ply extends beyond the edges of one of the at least two belt plies having a maximum belt width to have extension portions that extend at least 10 mm axially of the tire therefrom. The coating rubber of at least the extension portions of the belt cover ply is formed of rubber having a tan delta at a temperature of 60.degree. C. that is equal to or less than 0.1, and the ratio h/SH of a tire radial-direction length h between the edges of the extension portions and the edges of the belt ply having the maximum belt width to the tire section height SH is equal to or less than 1.5/100.

Abstract: Provided is an ultra-low profile pneumatic radial tire for SUV or the like having an aspect ration of 55% or less and a tire outer diameter of 720 mm or more, which has improved load durability while managing a weight reduction without deteriorating driveability. A carcass layer (4) thereof is configured as a single ply, and both ends thereof are folded back around left and right bead cores (7) so as to wrap bead fillers (8). A folded-back portion (4t) is wrapped on the inner side of an end of a belt layer (5) in a range not greater than 10% of the maximum width of the belt layer (5). The hardness of the bead fillers is 65 to 80 in terms of JIS durometer A hardness, and a height hb of the bead fillers (8) from a bead base is brought to 10 to 20% of the height H of a tire cross-section.

Abstract: An apparatus for positioning packing boxes relative to a covering sheet comprises a belt for conveying the sheet from a gluing unit to a device for centering the box on the pre-glued sheet and optical sensors for identifying the position of the sheet on a belt conveyor surface, the belt being made with at least two regions of the conveyor surface having contrasting colors.

Abstract: A device forms a radial flange on a bottom opening of a conate member having a longitudinal axis. The device has a die for receiving the conate member with the bottom opening extending from an open end of the die, a seal-forming cone having at least two radially-extendable sections and being removably located in the open end of the die, inside the conate member, and a handle, axially movable in the cone to extend the movable sections.

Abstract: Method for forming a dye sublimation image in a substrate, particularly a plastic substrate, and apparatus to perform the method. According to the method taught by the present invention, a substrate is disposed on a perforated platen and a dye carrier having an image formed thereon of a dye sublimation ink is disposed on the substrate such that the image is in contact with the substrate. The substrate, dye carrier and at least a portion of the perforated platen are then covered with a flexible membrane. A clamping pressure is then applied to the substrate and the dye carrier through the membrane. Once the clamping pressure is attained, the substrate and dye carrier are first heated, then cooled.

Abstract: Tools for compacting composite parts are disclosed. These tools are used while layers of composite material, such as tows or laminae, are being deposited onto a fabricating surface, such as a mold or other forming tool. The compacting tool is typically divided into a series of narrow segments, each segment able to advance or retreat individually so as to conform to the surface of a composite part being formed. Pressurized fluid, such as air or hydraulic fluid, or non-pressurized internal bladders with incompressible fluid, are used to evenly apply pressure to the segments in order to compact the material with which the tool and the segments are in contact. The compacting tool thus helps eliminate voids and helps the material conform to the desired shape on the forming tool.

Abstract: A hand-held electric sealer with dual heads includes a seat, a sealing module, a press cover, a supporting casing, and a battery cover. The seat has a central engaging rod and a first replacement element. The sealing module can be attached to, or detached from, the seat. The press cover includes a central engaging piece, a heat insulation block, and a second replacement element. Through engagement of the central engaging piece with the central engaging rod, the press cover can be selectively swung to press the heat insulation block against the sealing module, or to press the second replacement element against the first replacement element. The first replacement element and the second replacement element can be substituted with an appropriate module element upon demand on various functions.

Abstract: An ultrasonic welding apparatus is provided having an anvil preferably connected to a lever assembly. The lever assembly is preferably connected to a carrier via a holder, wherein the holder is pivotable with respect to the carrier, and the lever assembly is pivotable with respect to the holder. An urging device may also be provided to urge the anvil toward an ultrasonic hammer, more preferably away from the carrier.

Abstract: A flexible guide (1) for a mosquito net (100) of a type which is fixable to a window opening, comprising a plurality of rigid adjacent links (2a, 2b, 200), in which each link (2a, 2b 200) exhibits a pair of opposite flanks (5a, 5b, 205) which between them receive the mosquito net (100), and a connecting portion (6, 206) arranged transversally and fixed to the flanks (5a, 5b), each link (2a, 2b, 200) being provided with a seating (4, 204) for receiving a flexible strap element (3, 203) in order to form, with adjacently-situated links (2a, 2b), a single chain.

Abstract: A roller screen device includes a fixed sectional element (10) and a mobile sectional element (11) that is able to move parallel to the fixed sectional element inside a frame contained in which is a screen (13), the mobile sectional element (11) bearing a roller (12) inside it, wound on which is the screen (13), which, at the other end, is anchored to the fixed sectional element (10). Guide elements (14 and 24) for guiding the mobile sectional element (11) are positioned at the top and at the bottom of the screen (13) and fixed at one end to the mobile sectional element (11), while the other ends of the guide elements (14) slide into the fixed sectional element (10). Moreover provided is a system for tensioning the guides (14 and 24), which acts during the steps of opening and closing of the screen (13).

Abstract: A door system has an axis, a door attached at a first end to the axis for winding and unwinding upon the axis, and a tensioned member surrounding and partially engaging an outer layer of the door wound upon the axis. The tensioned member exerts a radial force to the outer layer of the door wound upon the axis, thereby ensuring that the door is consistently wound tightly upon the axis and permitting the fast unrolling of the door from the axis. Although the tensioned member exerts a radial force upon the door, it imparts no significant lateral forces to the door. Accordingly, the door can have a simple construction with material, cost and space savings.

Abstract: An elongated element for the frame of a panel system comprising a flexible sheet material includes a main profile to which an auxiliary profile is associated. The auxiliary profile is provided with means for anchoring an edge of the sheet material and it can be moved with respect to the main profile as a result of the driving of position control screws. The main profile is adapted to be fixed on the surface of a wall by connection means engaging a connection portion associated to it. The position control screws have a control formation which can be reached from the outside of the frame, when the main profile of the elongated element is fixed to a wall and the sheet material is anchored to the auxiliary profile.

Abstract: A lining support plate includes a base plate of cast metal and a plurality of pins which extend into the base plate and project from a support surface to anchor a friction lining material on the base plate. In the manufacture of the lining support plate, a support plate pattern (1) with a. plurality of cavities (4) in a lateral face is provided. Pins (6a-6d) are inserted into the cavities and partially protrude from the support plate pattern (1). The support plate pattern (1) and the protruding portions of the pins (6a-6d) are surrounded by a moulding compound which is compressed and/or cured. When the support plate pattern (1) is removed, the pins (6a-6d) are left behind in the moulding compound and a support plate casting cavity is formed. A melt is poured into the cavity, surrounding the portions of the pins (6a-6d) protruding into the cavity. Once the melt has solidified, the lining support plate can be removed from the mould.

Abstract: A single crystal seed for use in casting a single crystal article, consisting essentially of, in weight %, about 5.0% to about 40.0% Mo, up to 0.1% C and balance essentially Ni wherein the seed is disposed in a casting mold for casting a single crystal article.

Abstract: A set of dies are composed in order to remove excess metal from a casting with a press. A method of removing the excess metal from the casting includes the steps of: attaching a cutter to one of the stationary die side or the movable die side; setting a work on the other side; and punching excess metal of the work into a recess shape by one punching motion of the movable die with a plurality of blades from the first blade, which is smaller, to the final blade, which is larger and protruded, when the excess metal of the work is removed by a punching motion of the movable die conducted on the stationary die.

Abstract: A method and apparatus for the casting of metal components is disclosed. The apparatus includes a plunger for drawing molten metal from a crucible of hot metal and for forcing the drawn molten metal through the system, a hot runner assembly having a nozzle tip positioned adjacent the mold cavity, and a machine nozzle disposed between the plunger and the hot runner assembly. An adaptive and universal hot runner manifold having removable hot runner injectors fitted thereto is provided for use with a variety of castings.

Abstract: A metering device for a hot chamber die-casting machine includes a casting container attachable to a crucible of the hot chamber die-casting machine, a riser channel in a riser channel area, and a casting piston unit for metered conveying of melt out of the crucible via the riser channel. A heating device is provided with a flameless heating unit for active heating of at least a part of the riser channel area. The heating unit is placed inside a piston rod leadthrough bore, electrically insulated from the riser channel in a riser bore containing the riser channel, or in a heater receiving space specially provided in the casting container.

Abstract: A vapor-lift pump heat transport apparatus having a small heat resistance and a large heat transport capacity. A heat exchange circulating solution container has a first space and a second space communicating with the first space through a communication opening and contains a heat exchange circulating solution, and vapor thereof, in each space. A circulating solution transport passage includes a pipe connected to the solution outlet of the container and provided with a sensible heat releasing heat exchanger, a pipe disposed in the container, and a pipe connected to a vapor-liquid two-phase fluid inlet and provided with a heating heat exchanger. A vapor-liquid two-phase fluid flows into only the first space through the vapor-liquid two-phase fluid inlet. When the entrance of the vapor-liquid two-phase fluid has caused a pressure difference between the first and second spaces, a difference occurs between the positions of the vapor-liquid interfaces in the first and second spaces.

Abstract: In one embodiment, a method of making a heat exchanger is provided, comprising the steps of generating a stereolithography file from design data, slicing the stereolithography file into two-dimensional patterns, and depositing at least one layer of a material having a high thermal conductivity onto a top surface of a substrate to form a heat exchanger. Preferably, the heat exchanger does not require assembly of separate pieces to form the heat exchanger. In another embodiment a heat exchanger made by this embodiment of the method is provided wherein the heat exchanger may have a design comprising tapered fins and/or alternating airfoil cross-sections.

Abstract: A wireline cutter comprises a primary housing with a first axial bore configured to receive a wireline positioned within a well bore, and a first blade mounted within the primary housing and operable to cut the wireline. A method of cutting a wireline in a well bore comprises running a wireline cutter into the well bore, receiving the wireline within the wireline cutter, and cutting the wireline with the wireline cutter. A one-trip cutting system for use in a well bore comprises a wireline cutter, and a coiled tubing cutter. A method for cutting a coiled tubing with a wireline disposed therein comprises running a system comprising a wireline cutter and a coiled tubing cutter into the well bore, cutting the coiled tubing with the coiled tubing cutter, and cutting the wireline with the wireline cutter, wherein both cutting steps are performed in one trip into the well bore.

Abstract: A system for conducting earth borehole operations comprising a CT carrier, a reel of CT rotatably mounted on the CT carrier, a mast carrier, separate from the CT carrier, a mast mounted on the mast carrier and movable between a lowered position for transport and a position transverse to the horizontal, a top drive carried by the mast, the top drive being longitudinally movable along the mast and a CT injector on the mast carrier.

Abstract: The invention generally relates to an apparatus and/or a method for moving an round flexible member into and out of a well bore, and particularly, to an injector with two or more gripping members which bind the outer surface of the round flexible member; two or more actuators which cause the gripping members to bind or release the round flexible member; and at least one reciprocator for translating a gripping member to move the round flexible member, or for repositioning the gripping member. A method of translating a round flexible member is also provided which includes the steps of binding the outer surface of a round flexible member with at least one gripping members by engagement with an actuator, and translating a gripping member by reciprocator to move the round flexible member.

Abstract: A lubricator for use with a coiled tubing injector comprising an elongated housing having a first end and a second end. There is a guide system disposed in the housing for guiding coiled tubing passing through the housing, a first director proximal the first end of the housing to direct the coiled tubing in a first direction and a second director proximal the second end of the housing to direct the coiled tubing in a second direction.

Abstract: An electrical submersible pump assembly (ESP) includes a pump section, a motor section, and a seal section. In one embodiment, an exterior of the pump section defines a gripping indentation above the pump intake. Alternatively, a clamp member may be provided that surrounds the pump, wherein the clamp member defines the gripping indentation. A collet adapter is affixed to an upper end of a shroud. The collet adapter has gripping members that engage the gripping indentation for attaching the shroud to the electrical submersible pump assembly. The collet adapter is provided to ease installation of the motor shroud onto the ESP as well as to ease removal of the motor shroud from the ESP. The collet adapter of the present invention eliminates precise alignment and bolt-on requirements of typical motor shroud mounting techniques.

Abstract: A downhole tool for isolating zones in a well includes a mandrel, a sealing element disposed around the mandrel, an upper cone disposed around the mandrel proximate an upper end of the sealing element, an upper slip assembly disposed around the mandrel adjacent a sloped surface of the upper cone, a lower cone disposed around the mandrel proximate a lower end of the sealing element, a lower slip assembly disposed around the mandrel adjacent a sloped surface of the lower cone, and two element end rings. The two element end rings include a first element end ring disposed adjacent the upper end of the sealing element and a second element end ring disposed adjacent the lower end of the sealing element. The downhole tool includes two element barrier assemblies; each assembly disposed adjacent one of the two element end rings.

Abstract: A subpart of a drill string is described having an outer circumferential surface which is contoured and adapted to engage the wall of the borehole with a small angle of attack while exerting during rotary drilling operations an compacting pressure on mud cake and/or cuttings present in the annulus between the drill string and the borehole.

Abstract: An expansion joint with one or more communication medium bypass paths is described herein. At least some illustrative embodiments include a first axially flexible cylinder, one or more additional axially flexible cylinders positioned within the first cylinder, and first and second annular members each positioned at a opposite ends of, and each coupled to, the first cylinder and the one or more additional cylinders (the first and second annular members each including one or more apertures through each member). All cylinders concurrently extend and contract in axial length when the first and second annular members are respectively moved away from and towards each other. Annular spaces formed by each of the one or more additional cylinders and an externally adjacent cylinder, together with corresponding apertures of each of the first and second annular members, each provides at least one path for at least one communication medium.

Abstract: A product is described, the product is in liquid state and comprises: a first electrically non-conductive susceptor; a second electrically conductive susceptor; monomer molecules; and an initiator, suitable to trigger polymerization chain reaction of the monomer molecules, when activated by the first and/or the second susceptor. Further, a method is described to treat a wellbore including a zone, the method comprising the steps of: pumping the product above into the wellbore; placing the product in the vicinity of the zone; and applying an alternating magnetic field on the product.

Abstract: A sol of metallic alkoxide is pumped into a desired location in a wellbore and allowed to gel, creating solids in-situ. The sol is either unstabilized, requiring rapid placement before gelling, or the sol is stabilized, permitting off-site mixing. Sols can be stabilized with either surfactant or with interfacial polymers. Large concentrations of surfactant can be placed in the sol to create templates around which gelation occurs, creating porous solids.

Abstract: A method for controlling water condensation in the pores of a near wellbore region of a permeable formation through which wet natural gas flows into an inflow section of an oil and/or gas production well, the method comprising controlling fluid transfer through the near wellbore region such that development of a water bank resulting from condensation of water in said region is inhibited or promoted. If the well is a gas production well then development of a water bank may be inhibited by controlling pressure drawdown, cyclic well shut in, fracturing and/or injection of heat generating and/or water transporting chemicals.

Abstract: A memory logging system for determining the status of a sliding sleeve valve disposed within the borehole. The sliding sleeve contains signal inducing devices. A logging tool is conveyed through the sliding sleeve and time intervals between sensor excursions induced by the sleeve's signal inducing devices are recorded and stored within the tool memory. These data are subsequently recovered when the tool is returned to the surface of the earth, and sensor excursion data are processed in a surface processor to ascertain relative axial positions of the sliding sleeve outer housing and the insert. The condition of the sliding sleeve is determined from these relative axial positions.

Abstract: An embodiment is an apparatus for generating a driver gas, for recovering fluid from the Earth's subsurface. The apparatus includes a fuel reformer, adapted to react a fuel with water to produce carbon dioxide gas and hydrogen gas; a compressor, adapted to compress a portion of the carbon dioxide gas and a portion of the hydrogen gas; a gas injection unit, adapted to inject the portion of the carbon dioxide gas and the portion of the hydrogen gas compressed by the compressor, into a subsurface reservoir; a gas capture unit, adapted to capture a portion of the carbon dioxide gas and the hydrogen gas, that emerges from the subsurface reservoir; and a control module capable of using subsurface data to regulate operation of the gas injection unit. The apparatus may also include a power generator adapted to utilize a portion of the hydrogen gas to generate power, hence producing electricity without greenhouse gas emissions.

Abstract: Methods of preparing improved settable compositions free of Portland cement and methods of using such compositions in subterranean operations are provided. An example of a method of preparing such compositions may comprise providing an unhydrated mixture of raw materials comprising a silica component, an aluminum component, a magnesium component, a sodium component, a calcium component, a ferrous or ferric component, a sulfurous component, and a potassium component, wherein the mixture has been formed without heating any of the components to above about 3000° F.; and adding water to the unhydrated mixture of raw materials to form a settable composition.

Abstract: Methods of making and using wellbore casing are described, one method comprising providing a plurality of flow-through passages in a portion of a casing while the casing is out of hole; temporarily plugging the flow-through passages with a composition while out of hole; running the casing in hole in a wellbore intersecting a hydrocarbon-bearing formation; and exposing the composition to conditions sufficient to displace the composition from the flow-through passages while in hole. Methods of using the casing may include pumping a stimulation treatment fluid through the casing string and into a formation through the flow-through passages in the first casing joint; plugging the flow-through passages in the first casing section; and exposing a second casing joint of the casing string to conditions sufficient to displace the composition from the flow-through passages in the second casing joint.

Abstract: A watermelon mill has a smaller dimension for run in and a larger one for reaming out the window made by a window mill and passes through a smaller drift and then gets larger for more effective widening of the window. The cutters are preferably tungsten carbide or polycrystalline diamond inserts and they are mounted to blades that are ramped outwardly by a cone upon relative movement between the two. The body can be in multiple pieces that are rotationally locked and movable relative to each other longitudinally. Actuation to the larger dimension can be by setting down weight or by fluid pressure with the dimension getting smaller as a return spring allows the cutters to retract upon removal of applied pressure.

Abstract: A subterranean formation stimulation system, comprising a gas generator, a high pressure seal, and a fluid injection system. The high pressure seal may be a packer and or plug having an outer sealing surface on its outer periphery. The outer sealing surface is configured for metal to metal contact with the inner circumference of wellbore casing. The gas generator can be compressed gas or a propellant. A shaped charge can be included to activate the generator. The system is disposable in a wellbore on wireline, slick line, or tubing.

Abstract: A shock tool is adapted to a bottom hole tool assembly for isolating a zone in a subterranean formation accessed by a wellbore. Fracturing fluid such as nitrogen is accumulated at fracturing pressures uphole of the shock tool for subsequent and rapid release to the formation. The tool assembly can be suspended from a conveyance string in which fluid is accumulated for shock release through a valve of the shock tool and through an injection tool to the zone isolated by the injection tool. After a first zone is shocked, the tool assembly can be moved to a new zone, or multiple shocks can be applied cyclically at the selected zone.

Abstract: A ball type downhole lubricator valve features a ball rotating on its axis to open or close with control line pressure to an actuating piston. The ball is also shiftable to a locked open position. A cage surrounds the ball and retains opposed seats to it. The cage is made from one piece and tangential holes are drilled and tapped before the piece is longitudinally split with a wire EDM cutting technique. Fasteners to rejoin the cut halves properly space them to the original one piece internal dimension. Auxiliary tools allow determination of spacing of internal components so that a desired spring preload on the seats against the ball can be achieved.

Abstract: The object of the invention is to improve delivery of the multi-phase mixture, in particular hydrocarbons from a well, and to limit the free gas volume. According to the invention, this object is attained in that a partial liquid flow (13) is split off on the pressure side from the main delivery flow and guided to the high-pressure side of at least one ejector pump (2) arranged on the suction side as an auxiliary delivery device. The pump installation provides a feed line (7) connecting the pressure chamber of the displacement pump (1) with the high-pressure side of at least one ejector pump (2), whereby the ejector pump (2) is arranged on the suction side in the delivery direction of the displacement pump (1).

Abstract: A method for retrofitting a downhole drill string with a flow through subassembly having a hollow outer body or barrel with a plurality of outwardly extending blades. Fluid flow inlets are provided in the lower section of the body below the blade openings and flow outlets are provided in an upper section above the blades. A fluid flow bypass channel is formed in the outer body and extends between said blades and from said fluid inlet to said fluid outlet. Drilling fluids outside of the subassembly may flow through the inlet, up the fluid flow bypass channel and out the outlet thereby bypassing any plug or pack-off formed between the subassembly and the well bore. Thus, an existing subassembly may be retrofitted to provide a fluid flow bypass channel around the blades.

Abstract: An apparatus is shown for installing a pulling a submersible pump from a well bore where the pump is supported on a length of flexible tubing. The apparatus has a pivot frame located on a transportable base frame. A take up reel for the flexible tubing is also supported on the pivot frame by a pair of pivoting support arms. The take up reel is centered over the well bore by pivoting the reel on the support arms between a collapsed and a vertical work position. The reel can be further centered by pivoting the pivot frame in a horizontal plane relative to the base frame.

Abstract: An isolation system for an oil and gas well is described wherein the system comprises an isolation section and a first isolation device integral with the section and a second isolation device sealingly engaged to the section. The first isolation device may be a pressure-actuated valve and the second isolation device may be a plug.

Abstract: A mobile smoke control and fire protection device for buildings is provided. The device comprises a sealing unit that can be applied to, or inside, an opening of a wall, a ceiling or a floor, is adapted to the opening in terms of the shape and size thereof, and is provided with at least one passage for people and/or at least one passage for tools, firefighting equipment, and the like. The passage for people and/or the passage for equipment can be least partially covered.

Abstract: A combination fire detection and fire suppression system may include a fire detection system configured to detect an undesirably high temperature associated with an area. The fire detection system may include a temperature sensor including a temperature sensor array and a fire alerting system associated with the temperature sensor. The fire alerting system may be configured to receive information from the temperature sensor and generate a warning signal based on an undesirably high temperature associated with the area. The fire detection system may include a fire control panel configured to receive the warning signal. The system may also include a fire suppression system including a fire suppressant delivery system configured to provide at least one fire suppressant agent to the area associated with the undesirably high temperature.

Abstract: The nutrient device of the present invention includes a ground having a ground surface. The coulter is mounted for rotation about a coulter axis and the coulter penetrates the ground and makes the ground penetration below the ground surface. A cleaning wheel is mounted for rotation about a cleaning wheel axis, and the cleaning wheel extends upwardly from engaging the coulter to a cleaning wheel point spaced away from the coulter. A conduit is positioned to deliver a nutrient onto the coulter for dispensing the nutrient into the ground penetration. A closing wheel is positioned adjacent the rear of the coulter and the cleaning wheel for closing the ground penetration.

Abstract: A ground opener that is allowed to caster in one direction is associated with a pair of arms connected by a pivot connection that allows one arm to move relative to the other arm. The movable arm is forced against the stationary arm when the ground opener impacts the soil as the ground opener is pulled along a relatively straight travel path. When the ground opener is turned radially from the straight travel path, the movable arm may cast away from the stationary arm. The disc opener is coupled to the movable arm through a central hub and, as such, the trailing edge of the disc opener will move away from the stationary arm as the disc opener is turned. When the disc opener has completed the turn, the torque on the disc opener will lessen thereby allowing the movable arm to move back toward the stationary arm.

Abstract: A sectored disc assembly, removable disc sector, and method of replacing a disc sector are disclosed for use with a soil opener that uses a disc assembly to open the soil prior to injection of a fertilizer or seed into the ground. The sectored disc assembly includes a rotatable hub and a plurality of disc sectors cooperatively forming a substantially continuous disc around the hub. Connectors, such as bolts, secure each of the disc sectors to the hub. The disc sector includes a body with radially inner and outer margins and side margins that are configured for continuous abutment with adjacent side margins of other disc sectors. The method of replacing a disc sector includes removing the connector securing the disc sector to the hub, moving the disc sector radially outwardly away from the hub, placing a replacement disc sector into contact with the hub, and inserting the connector.

Abstract: The blade apparatus includes a connection blade portion which is provided at its lower end with a central blade portion including a straight first cutting edge and having a second cutting edge which extends continuously with the first cutting edge through a predetermined angle rearwardly, and an end blade portion having a third cutting edge which extends continuously with a second cutting edge through a predetermined angle forwardly, wherein front surfaces of the blade portions are concave curved surfaces which are continuous from the upper end to the lower end, across line between the connection blade portion and the end blade portion and a cross point between the second cutting edge and the third cutting edge are located rearward of the cross point of the first cutting edge and the cross line between the central blade portion and the connection blade portion, and at least a central main region of the central blade portion is made of steel plate, and at least the connection blade portion and the end blade po