Abstract: Provided is a method of installing a heat insulating block on a furnace shell which enables a heat insulating block to be firmly fixed to a furnace wall but does not require much time and costs for making the heat insulating block, and which further offers good workability at a site. The method of installing a heat insulating block on a furnace shell includes: inserting a beam of a fixture into a fold of an inorganic fiber aggregate mat that is folded up to form a heat insulating block; and fixing the fixture and a furnace shell to each other.

Abstract: Provided are a magnesia carbon brick which does not include graphite yet has excellent spalling and corrosion resistances, and a method for producing thereof. The brick is obtained by adding an organic binder to a refractory raw material mixture followed by kneading, molding, and heat-treating, wherein the mixture includes total 0.1 to 2.0 mass % of pitch and/or carbon black, total 0.1 to 1.0 mass % of aluminum and/or aluminum alloy, 3.0 to 10.0 mass % of magnesia having particle diameter of less than 0.075 mm, and 87.0 to 96.0 mass % of magnesia having particle diameter of 0.075 to 5 mm; and a mass ratio of magnesia having particle diameter of 1 to 5 mm to that of 0.075 to 1 mm is 1.66 to 2.34; graphite is not included therein; and an apparent porosity thereof after heat-treatment under reductive atmosphere at 1400° C. for 3 hours is 8.0% or less.

Abstract: Many substantially identical refractory bricks are assembled into completed horizontal ring rows neatly nested into laterally curved copper stave coolers surrounding the ring. Each brick “locks” into horizontal channels between pairs of parallel horizontal protruding ribs on the hot faces of the stave coolers. Every stave cooler is provisioned with a full covering of the refractory bricks after the stave cooler is mounted inside a corresponding steel containment shell. None of the refractory bricks are permitted to be finished bridging between adjacent stave coolers in the same horizontal row. Each brick is installed in their respective stave coolers with crushable or deformable mortar filling the channels. Each brick hooks a “toe” just under and into an upper of the pair of horizontal ribs, and then rotates in down with favorably oriented and directed earth's gravity to stay in place at least until a next upper row of bricks in a superior horizontal ring “lock” them in a second way.

Abstract: The invention relates to a refractory (fireproof) impact pad (also called impact pot).

Abstract: A hearth for a metallurgical reactor, in particular for a blast furnace, has an outer shell and an annular wall lining of refractory material inside the shell, the wall lining having a lower region with a multi-layered construction, a radially inner layer faces the interior of the hearth and includes at least one inner ring of refractory elements, radially outer layer faces the outer shell and has at least one outer ring of refractory elements, where in the at least one inner ring elements are made of a first carbonaceous refractory material that is different from one or more carbonaceous refractory materials of the elements in the outer layer such that, the first refractory material contains, in a proportion of at least 5% by mass in total, at least one property-enhancing additive other than metallic silicon or silicon carbide. In beneficial combination therewith, the at least one inner ring has a wall thickness of less than 45%, of the corresponding total wall thickness of the wall lining.

Abstract: In a steel ladle used for handling molten steel, a precast ladle barrel ring forms part of a refractory structure that covers the bottom wall and side wall of the steel ladle. The precast ladle barrel ring is comprised of a monolithic annular ring formed of a high-temperature, cast refractory. The annular ring further includes means for positioning the precast ladle barrel ring in a steel ladle.

Abstract: A refractory bottom lining for lining the bottom of a metallurgical vessel. The refractory bottom includes a stepped portion and an impact portion. The impact portion is formed of a first refractory material. The stepped portion is formed of a second refractory material and is disposed around the impact portion. The stepped portion includes an upper surface that has a plurality of discrete surface sections. The plurality of discrete surface sections includes an uppermost surface section, at least two intermediate surface sections and a lowermost surface section. Each surface section has a different elevation such that the uppermost surface section has a highest elevation and the lowermost surface section has a lowest elevation. The uppermost surface section, the at least two intermediate surface sections and the lowermost surface section define a continuously downward stepped path from the uppermost surface section to the lowermost surface section.

Abstract: In a steel ladle used for handling molten steel, a precast ladle barrel ring forms part of a refractory structure that covers the bottom wall and side wall of the steel ladle. The precast ladle barrel ring is comprised of a monolithic annular ring formed of a high-temperature, cast refractory. The annular ring further includes means for positioning the precast ladle barrel ring in a steel ladle.

Abstract: Presented are an insulation brick and the method of using an insulation brick to create a thermal lining. A set of corrugations are formed into a sidewall of the brick to increase the thermal insulation. A first end of the insulation brick has a convex portion while the second end of the insulation brick has a convex portion. This allows a first insulation brick to mate with another brick in an end to end configuration.

Abstract: A roof system for an electric arc furnace includes a skew removably attached to the electric arc furnace, a lining of refractory material affixed to the skew, and a delta composed of a refractory material. The delta has at least one aperture capable of receiving an electrode. The delta fits onto and is supported by the refractory lining that is affixed to the skew.

Abstract: A method of securing a precast refractory shape within a refractory structure, comprising the steps of forming a precast refractory shape by casting a refractory shape to have a plurality of spaced-apart cavities formed in an outer surface thereof; positioning the precast refractory within a refractory structure; and casting a refractory material around the precast refractory shape such that the refractory material covers the outer surface of the precast refractory and fills the cavities.

Abstract: Presented are an insulation brick and the method of using an insulation brick to create a thermal lining. A set of corrugations are formed into a sidewall of the brick to increase the thermal insulation. A first end of the insulation brick has a convex portion while the second end of the insulation brick has a convex portion. This allows a first insulation brick to mate with another brick in an end to end configuration.

Abstract: A taphole structure of a melting furnace includes: a sleeve made of a fire-resistant brick, which is disposed inside a tapping hole provided in a furnace wall brick; and a ramming material which fills a gap between the sleeve and the tapping hole for fixing the sleeve. In addition, a repair method of the taphole which has expanded due to wear of a first ramming material during tapping, includes: forming a dismantled surface having a straight line shape by dismantling and removing a worn portion of the first ramming material in a straight line from an outer surface side toward an inner surface side of a furnace wall; and then filling a second ramming material into a gap between the dismantled surface having the straight line shape and a first sleeve for sealing.

Abstract: A refractory lining system comprises an inner refractory layer; and an outer layer located outside of the inner refractory layer, the outer layer comprising: a plurality of layer segments; and at least one control joint located between the plurality of layer segments, the at least one control joint configured to allow expansion and contraction in the outer layer. A segment of an outer layer of a refractory lining comprises an edge shaped corresponding to a control joint configured to allow expansion and contraction in the outer layer.

Abstract: A refractory bottom for a metallurgical vessel comprised of a bottom lining having a bottom surface that is dimensioned to overlay a bottom of a metallurgical vessel and an upper surface. The upper surface is comprised of a plurality of discrete sections that include an uppermost section, an intermediate section and a lowermost section. Each section has an upper surface at a discrete elevation such that the upper surface of the uppermost section has a highest elevation and the upper surface of the lowermost section has a lowest elevation. The upper surface of the uppermost section, the intermediate section and the lowermost section comprise a series of successive stepped sections that define a stepped path from the uppermost section downward to the lowermost section. Each successive section of the upper surface is lower than a preceding section.

Abstract: Disclosed is a magnesia-carbon based sleeve brick for steelmaking converters, which is obtained by adding, to a refractory raw material mix containing 60 to 95 mass % of a magnesia raw material and 5 to 20 mass % of graphite, a metal powder of one or more selected from the group consisting of Al, Si, Mg, Ca, Cr and an alloy thereof, in an amount of greater than 3 to 6 mass %, and an organic binder, in addition to 100 mass % of the refractory raw material mix, and subjecting the resulting mixture to kneading, forming and heat treatment, wherein the sleeve brick is used under a condition that a thickness thereof is set at 70 mm or less. This makes it possible to prevent cracking which would otherwise occur in the sleeve brick itself, to allow the sleeve brick to have enhanced durability. One or more selected from the group consisting of B, B4C, MgB2, CaB6, and CrB may be further added in an amount of 0.

Abstract: A device for use in a molten metal pump helps alleviate jams between a rotating rotor and stationary inlet. The device includes an inlet structure including one or more openings and a displacement structure that preferably includes one or more rotor blades. The inlet structure and displacement structure are connected to one another (preferably, but not necessarily, as a unitary piece), thus enabling them both to rotate. A pump including the device is also enclosed. The invention further includes a bearing surface for an impeller or for a device according to the invention, wherein the bearing surface includes grooves that help reduce molten metal build up between the bearing surface of the impeller or device and the bearing surface of a pump chamber.

Abstract: An impact pad, for use in a T-shaped tundish, comprises a base having an impact surface and an outer side wall extending upwardly therefrom and defining an interior space having an upper opening for receiving a stream of molten metal, the interior space being divided into two regions by a separating wall provided with at least one passageway for the molten metal stream. The separating wall is at least three times higher than the outer side wall and is inclined with respect to the vertical. This impact pad increases the homogeneity of the molten steel cast from the different outlets of the T-shaped tundish and provides equal or relatively similar residence times of the molten steel discharged through the different outlets of the tundish. This impact pad also permits a fast transition of the steel quality at ladle change while retaining the advantages of conventional impact pads.

Abstract: Refractory furnace covers and methods for their construction are provided. A method includes providing a molding form base having a molding surface, providing an outer molding frame on the molding form base, and providing at least one inner molding member disposed across and dividing the molding surface into a first molding section and a second molding section. The inner molding member has a first molding surface and a second molding surface located adjacent to and facing the first and second molding sections, respectively, the inner molding member having a protrusion located along the length of the first molding surface. A first molded section of the furnace cover is cast between the outer molding frame and the first molding surface of the inner molding member, the inner molding member is removed, and a second molded section of the furnace cover is cast between the outer molding frame and the first molded section of the furnace cover.

Abstract: A process for producing a float bath bottom refractory brick which can suppress a reaction with Na2O from glass at the surface of the refractory brick and thereby prevent flaking phenomena, which process comprises adding a potassium compound to a clayey material comprising from 30 to 45 mass % of Al2O3 and from 50 to 65 mass % of SiO2 and having a Na2O content of at most 1 mass %, so that the K2O content in the float bath bottom refractory brick to be produced would be from 2 to 4 mass %; and a refractory brick useful for a float bath bottom for production of plate glass by a float process.

Abstract: A refractory bottom for a metallurgical vessel comprised of a bottom lining having a bottom surface that is dimensioned to overlay a bottom of a metallurgical vessel and an upper surface. The upper surface is comprised of a plurality of discrete sections that include an uppermost section, an intermediate section and a lowermost section. Each section has an upper surface at a discrete elevation such that the upper surface of the uppermost section has a highest elevation and the upper surface of the lowermost section has a lowest elevation. The upper surface of the uppermost section, the intermediate section and the lowermost section comprise a series of successive stepped sections that define a stepped path from the uppermost section downward to the lowermost section. Each successive section of the upper surface is lower than a preceding section.

Abstract: An insulating refractory lining for insulating the inner surface of a vessel defined by a metal shell. The refractory lining is comprised of a first refractory layer overlaying an inner surface of a metal shell. The first refractory layer is comprised of a cast refractory material and has a first side facing the metal shell and a second side facing away from the metal shell. A plurality of discrete, spaced-apart cavities are formed in the first side of the first refractory layer. The cavities define air pockets between the metal shell and the first refractory layer.

Abstract: An impact pad for a bottom lining of a metallurgical vessel, such as a ladle. The impact pad reduces wear to side walls of the metallurgical vessel by controlling the flow of an incoming stream of molten metal to minimize splashing and turbulence. The impact pad includes a frame portion and a bottom wall portion. The frame portion and bottom wall portion define an interior cavity for receiving the stream of molten metal.

Abstract: A furnace sidewall structure of a rotary hearth furnace for making direct reduced iron which is agglomerated iron ore or waste iron oxide containing a reducing agent on a rotary hearth by heating or for heating at least one steel piece, wherein the rotary hearth furnace includes an outer furnace sidewall and an inner furnace sidewall, wherein at least one of the outer furnace sidewall and the inner furnace sidewall is polygonal. The furnace sidewall structure can be prepared with lower manufacturing costs relative to conventional circular profile rotary hearth furnace with respect to the furnace sidewall. The production thereof is easy with respect to manufacturing and with respect to the fact that the dimensional accuracy of the manufactured furnace sidewall can be easily adjusted. Also, there is associated a shorter installation/construction work period and a reduction in the installation/construction cost.

Abstract: A lining for a ladle used to handle molten metal. The lining is comprised of a first course of like, refractory bricks arranged horizontally in the ladle, the first course having an upper surface. A second course of like refractory bricks is arranged to spiral within the ladle. The second course is disposed on the first course, and the second course has an upper surface. A starter comprised of at least one refractory component is dimensioned to form a contoured ramp surface. The starter is disposed between the first course and the second course of like refractory bricks. The ramp surface at one end of the starter set is aligned with the upper surface of the first course and the ramp surface at another end is aligned with the upper surface of the second course.

Abstract: The invention relates to a bottom structure of a suspension smelting furnace to be used in a smelting furnace (1), in the reaction space (2) whereof of sulfidic raw material containing metal, such as copper, nickel or lead, is smelted in the presence of an oxygen-bearing gas and slag-forming agent, in order to render the metal in a form that is advantageous for further treatment, and where the created molten phases (5, 6) are settled onto the bottom (3) of the smelting furnace in order to separate the molten phases form each other, when the temperature of the molten phases is within the range 1150-1450° C. According to the invention, the bottom structure includes at least one arched lining layer (7) inclined in the longitudinal direction of the smelting furnace, so that the temperature on the surface (89 that is opposite to the surface that gets into contact with the molten phase is below 800° C.

Abstract: The invention relates to a fire resistant ceramic part which can be embodied in the form of an impact pot or a casting gutter and has the following characteristics:—a base (10); at least two walls (12, 14) which extend from opposite sections (10l, 10r) of the base (10) such that at least some sectors (12.1, 12.3, 12.4) of the inner surfaces thereof run at an angle >0 and <90 degrees from a plane E-E, perpendicular to the base (10), and at opposite inclinations;—an opening (O) is configured between free ends (12r, 14r) of the walls (12, 14);—the distance (dmin, qmin) between the walls (12, 14) is smaller in at least one sector (11) between the base (10) and the opening (O) than it is in the areas (12u, 14u; 12o, 14o) located adjacent the opening (O) and the base (10).

Abstract: A lining at the restriction part of a converter capable of more suppressing the falling of bricks than before even if the bricks at the restriction part are stack aslant and increasing a workability at the time of installation, wherein the shell of the converter at the restriction part is lined with firebricks by tilt stacking to protect the restriction part against melting by hot molten steel and slag, a projectedly bent locking part is provided on the upper and lower surfaces of the firebricks, and the locking part on the lower surface of the firebrick stacked on an upper side is overlapped with the locking part on the upper surface of the firebrick stacked on a lower side.

Abstract: A tundish impact pad for use in the continuous casting of molten metal is described that includes a base plate having an upper impact surface surrounded, at least in part, by a sidewall defining passageways. The impact pad is adapted to receive and deflect an incoming stream of molten metal, and permit outflow of the deflected stream through the passageways and the open top surface of the pad. Vaulted-stepped features surrounding the passageways and/or weir-like walls assist in directing the outflow. The division and distribution of the outflow facilitates the development of plug flow in the molten metal between the impact pad and the tundish outlet.

Abstract: A lining for a bottom of a metallurgical vessel, comprising an impact pad having a plurality of close-packed, pre-formed, high-temperature, high-density refractory bricks, the pad having an upper impact surface, and a monolithic slab of a high-temperature refractory material encasing the pad, the slab encasing the pad wherein the upper surface of the impact pad is exposed.

Abstract: An impact pad formed from a refractory material for reducing the turbulence of a molten metal poured therein. The impact pad has a plurality of sidewalls, each sidewall having a plurality of spherically shaped portions. The spherically shaped portions disperse the molten metal in a variety of directions.

Abstract: The present invention relates to a grooved refractory pouring tube for pouring a molten metal between an upper metallurgical vessel and a lower metallurgical vessel, a refractory assembly incorporating such a pouring tube, and a casting installation incorporating such an assembly.

Abstract: A melting liner for an induction melting furnace includes an integral foot portion for locating a lip portion of the melting liner in a convenient position for pouring molten metal.

Abstract: A refractory hanger brick for high temperature industrial furnace roof construction having an elongated upwardly extending refractory portion having a generally rectangular cross section and a lower refractory base portion having a generally rectangular lower face, each side of the base portion having a base length greater than a corresponding side of the elongated upwardly extending refractory portion so as to provide support for insulating material and/or adjacent filler bricks. The upper end of the elongated upwardly extending refractory portion distal from the lower refractory base portion forms a hanger recess along opposite sides of the upper end. At least one generally laterally extending lug is disposed above each of the hanger recesses to retain the hanger in a fixed position and to provide at least one hanger position along the upper end opposite sides.

Abstract: A tundish impact pad formed from refractory material, the impact pad (1) comprising a base (3) having an impact surface (5) which in use faces upwardly to receive molten metal poured onto the impact pad, and a wall (7) extending upwardly from the base around at least part of the periphery of the impact surface, the wall including an overhang (9) projecting over a peripheral region (11) of the impact surface (5), the overhang (9) including a plurality of protrusions (13) which project further over the impact surface (5) than the remainder of the overhang (5).

Abstract: An annularly shaped piece (28) formed from refractory material is provided for a tundish (1) for continuous casting of metals for enclosing a plasma torch (18) for heating liquid metal (4). The interior wall (29) of the annularly shaped piece defines a space which widens with progression toward the bottom, the piece having an upper opening (30) and a lower opening and accommodating penetration of the lower end region of the torch (18) into the space. The annularly shaped piece (28) is fixed to a cover (24) or to the refractory walls (3) of the tundish (1), and/or is fixed to one or more dividing walls (10) which delimit a heating compartment (13) in the interior of said tundish (1), wherewith the space defined by the interior wall (29) of said piece (28) widens with progression toward the bottom of the tundish (1).

Abstract: A lid for a melting furnace includes preformed refractory side panels in the form of circular sectors and a center panel in the form of a circular or octagonal closure. The side panels are inclined upward and inward from support provided by a lid ring encircling the lid. The center panel is horizontal. The edges of the panels are according to one embodiment beveled to mutually support one another and contain keyways filled with keys that structurally interconnect the panels. The side panels may include a plurality of blocks with step portions for mutual engagement between a corresponding skewback and the center panel.

Abstract: An interconnected precast module refractory leveling assembly for a metallurgical vessel is disclosed. The precast modules of the instant invention compensate for the sloping bottom of a metallurgical vessel. At least one precast module is disposed in each of two partial rings each of which is essentially a mirror image of the other so that the height of the leveling assembly varies substantially uniformly from a high point where the two mirror image portions join to a low point 180 degrees of arc displaced therefrom where the two portions again join. Each of the refractory precast modules has a slight taper in height so that the ends of each precast module are the same height as the juxtaposed ends of the adjoining precast module.

Abstract: A ladle brick leveling set for high temperature molten metal ladles in which specially shaped refractory bricks are disposed in a slightly sloping geometrical configuration so as to compensate for a sloping bottom of a high temperature molten metal ladle. The bricks are disposed in two partial rings each of which is essentially a mirror image of the other so that the height of the leveling set varies substantially uniformly from a high point where the two mirror image portions join to a low point 180 degrees of arc displaced therefrom where the two portions again join. Each of the refractory bricks has a slight taper in height so that the ends of each brick are the same height as the juxtaposed ends of the adjoining bricks.

Abstract: A dam surrounding a slag tap on a refractory covered, boiler-tube floor for holding back a protective slag layer. The dam is comprised of a plurality of adjacent refractory blocks mechanically secured to the refractory covered, boiler-tube floor near the slag tap. Each refractory block is shaped to brace an adjacent refractory block against motion toward the slag tap. Additional dams are used when a single dam is not sufficient to cover the entire surface of the floor with slag.

Abstract: Refractory materials (typically refractory bricks) having the exposed working surface treated to form a silica sand glazed surface for their utilization in iron ore reduction reactors, for example of the moving bed type, fluidized bed type, rotary kilns, or the like, and method and apparatus for treating refractory bricks before installation as well as for treating refractory linings already installed in existing iron ore reduction plants, which produce direct reduced iron (DRI), prereduced iron ores, or the like. Some operational problems, involving adherence and buildup of aggregates from small metallic iron particles on the refractory lining of said reduction reactor, are minimized with a corresponding decrease in operating costs and an increase in the availability of the DRI producing plant.

Abstract: A rigid ceramic refractory base for a plural-stack annealing furnace--such as an eight-stack furnace that has two "four-stack rows" or "halves" arranged side by side--is assembled atop a base support structure utilizing a novel set of cast refractory segments, including spaced sets of inner segments, with each set of inner segments being surrounded by a sub-set of outer segments. Defined between each set of inner segments and its surrounding sub-set of outer segments is a circular inner seal positioning trough that opens upwardly, and that has a tapered cross section that narrows with depth. A resilient but reinforced inner seal of novel form is installed in each of the troughs, with each of these seals utilizing upper and lower blankets of refactory fiber material that sandwich a plurality of elongate refractory fiber modules arranged end-to-end to circumferentially fill the trough.

Abstract: A refractory brick that has a rear portion with a geometrical concavity on one side and a corresponding convex projection on the other side, the concavity and projection being matched so that the concavity mates with the corresponding projection of a similar refractory brick when the two are disposed in side-by-side relationship. Extending perpendicular from the base portion is a generally rectangular projection such that when a plurality of bricks are disposed in a side-by-side array, they are locked together by the mating concavities and projections, and the generally rectangular projections extend inwardly to form a thicker lining to withstand the force of a tap stream of molten metal for a longer duration.

Abstract: A rigid ceramic refractory base for a single-stack annealing furnace is assembled atop a base support structure utilizing a novel set of cast refractory segments, including a pair of C-shaped inner segments and four arcuate outer segments. Defined between the assembled inner and outer segments is a circular inner seal positioning trough that opens upwardly, and that has a tapered cross section that narrows with depth. A resilient but reinforced inner seal of novel form is installed in the trough utilizing upper and lower blankets of refractory fiber material that sandwich a plurality of elongate refractory fiber modules arranged end-to-end to circumferentially fill the trough.

Abstract: A rigid ceramic refractory base for a plural-stack annealing furnace is assembled atop a base support structure utilizing a novel set of cast refractory segments, including spaced pairs of C-shaped inner segments that each are surrounded by a sub-set of outer segments. Defined between each set of inner segments and its surrounding sub-set of outer segments is a circular inner seal positioning trough that opens upwardly, and that has a tapered cross section that narrows with depth. A resilient but reinforced inner seal of novel form is installed in each of the troughs, with each of these seals utilizing upper and lower blankets of refractory fiber material that sandwich a plurality of elongate refractory fiber modules arranged end-to-end to circumferentially fill the trough.

Abstract: A rigid ceramic refractory base for a plural-stack annealing furnace is assembled atop a base support structure utilizing a novel set of cast refractory segments, including spaced pairs of C-shaped inner segments that each are surrounded by a sub-set of outer segments. Defined between each set of inner segments and its surrounding sub-set of outer segments is a circular inner seal positioning trough that opens upwardly, and that has a tapered cross section that narrows with depth. A resilient but reinforced inner seal of novel form is installed in each of the troughs, with each of these seals utilizing upper and lower blankets of refractory fiber material that sandwich a plurality of elongate refractory fiber modules arranged end-to-end to circumferentially fill the trough.

Abstract: A vessel for very high temperature materials having an upper terminus with an annular surface and at least one refractory abutting the inner surface of the vessel and extending across the annular surface and an embodiment wherein a wedge-shaped member abuts the inner surface of the vessel.

Abstract: A rigid ceramic refractory base for a single-stack annealing furnace is assembled atop a base support structure utilizing a novel set of cast refractory segments, including a pair of C-shaped inner segments and four arcuate outer segments. Defined between the assembled inner and outer segments is a circular inner seal positioning trough that opens upwardly, and that has a tapered cross section that narrows with depth. A resilient but reinforced inner seal of novel form is installed in the trough utilizing upper and lower blankets of refractory fiber material that sandwich a plurality of elongate refractory fiber modules arranged end-to-end to circumferentially fill the trough.

Abstract: An improvement is provided in apparatus for retaining refractory in a metallurgical vessel. The improvement includes a wedge-shaped metal ring extending along the inner periphery of a metal shell of the vessel adjacent to an opening at one end thereof and refractory material having an angular surface for abutting an angular surface of the metal ring.

Abstract: Method and geometrical arrangement of refractories within a high temperature vessel. A protuberance near the periphery of the vessel opening is formed on an inner surface and a ring of trapezoidally-shaped refractory brick is positioned such that a sloping surface of each of the trapezoidally-shaped brick is preferably initially in contact with an adjacent surface of the protuberance. When the interior of the vessel is heated and the brick expand, they tend to ride upwardly, with the sloping surfaces urging the brick inwardly thereby increasing lateral friction therebetween, thereby holding them in place and preventing them from moving even when the vessel is tilted or turned upside down.