Abstract: A boiler tube protector having a cylindrical or semi-cylindrical shape and adapted to be attached around an outer peripheral face of a boiler tube with mortar, which boiler tube protector includes a plurality of ceramic bodies closely arranged along their parting planes, wherein the parting planes includes a restraining portion for restraining slippage of each of the ceramic bodies.

Abstract: Water-cooled pipes of the type utilized to support steel workpieces in reheat furnaces and the like are insulated by preformed, rigid refractory members. Threaded studs are welded to opposing surfaces of the pipe or the web between a pair of pipes. The pipe(s) are then covered by a ceramic fiber blanket. A pair of the refractory members, each of which contains an aperture through which one of the studs is received, is positioned so as cover the pipe(s) and blanket. Nuts are fastened to the studs to hold the refractory members in place. The refractory members are sized and positioned so that gaps exist between them so as to allow for thermal expansion. These gaps may be filled with blanket insulation or heat-resistant plastic. The remaining portions of the apertures are also filled with heat-resistant plastic.

Abstract: A plurality of tube shields interlock with each other to protect the weld of a securement s strap used to secure the shields to a tube of a power plant. The tube shield comprises a semi-cylindrical longitudinally extending tube member terminating at a first and second end. The first end is provided with a tongue portion and a stepped portion. The second end is provided with a flanged portion and a pair of longitudinally extending bayonets. A securement strap is wound about a tube to be protected and the tongue portion of the tube shield. Each end of the securement strap is then welded to the tongue portion. A second tube shield is then placed adjacent to the first tube shield. The flanged portion of the second tube shield overlaps the tongue portion, securement strap, and stepped portion to provide protection from the hostile environment of the boiler.

Abstract: A tube wall, division wall, or wing wall section for a circulating fluidized bed boiler with improved erosion resistant characteristics has a reduced diameter tube section adjacent the refractory covered by an abrasion resistant refractory tile. The refractory tile is mounted to the reduced diameter tube section with the upper edge of the refractory tile outside of or not extending beyond a solids fall line of solids in the fluidized bed to eliminate exposed discontinuities.

Abstract: A heat-resistant assembly to shield boiler tubes which does not entail a thick heat-resistant block. This structure would be interposed between the boiler tubes and the combustion gases. Such a structure would be distinguished by the fact that it comprises heat-resistant block 16, itself composed of curved portion 16a, whose inner surface at one point comes in contact with the aforesaid boiler tube 11, and connecting portions 16b, and the aforesaid boiler tube assembly 12. The interlocking attachment structure which interlockingly secures these two components together in such a way that the block can be mounted or removed comprises recess 17, 58 or 68 and tongue 18, 59 or 69.

Abstract: A generator which can prevent deterioration of the chilling performance and corrosion, and can provide a high degree of reliability and long service life is disclosed. The high-temperature generator comprises a combustion chamber for flowing a combustion gas therein, a first tube assembly and a second tube assembly provided in the combustion chamber each of which has a plurality of heat transfer tubes for containing liquid therein. The first tube assembly comprises a plurality of bare tubes and is arranged at an upstream of the second tube assembly. The second tube assembly comprises a plurality of finned tubes provided with fins on the outer surface thereof. The heat transfer tubes are arranged in a staggered manner in a direction of the combustion gas flow within each of the first tube assembly and the second tube assembly.

Abstract: A plurality of tube shields interlock with each other to protect the weld of a securement strap used to secure the shields to a tube of a power plant. The tube shield comprises a semi-cylindrical longitudinally extending tube member terminating at a first and second end. The first end is provided with a tongue portion and a stepped portion. The second end is provided with a flanged portion and a pair of longitudinally extending bayonets. A securement strap is wound about a tube to be protected and the tongue portion of the tube shield. Each end of the securement strap is then welded to the tongue portion. A second tube shield is then placed adjacent to the first tube shield. The flanged portion of the second tube shield overlaps the tongue portion, securement strap, and stepped portion to provide protection from the hostile environment of the boiler.

Abstract: The present invention relates to a refractory shield for protecting a superheater tube against fluid attack comprising first and second partial-tubes (2, 8), each partial-tube having a C-shaped cross section, the C-shaped cross section defining first (3, 9) and second (4, 10) ends; wherein the ends of the partial-tubes are opposably engaged, and wherein the partial-tubes comprise means (5) for preventing radial movement of the first partial-tube relative to the second partial-tube.

Abstract: An alloy having an excellent corrosion resistance and workability and being suitable particularly for seamless tubes of the industrial waste incineration boiler. The alloy consists essentially of, in weight %,:______________________________________ up to 0.05% C, up to 0.5% Si, up to 0.5% Mn, up to 0.01% P 20-25% Cr, 8-12% Mo, more than 0.5% and up to 1.0% Nb, more than 15% and up to 20% Fe, up to 0.4% Al, up to 0.1% in total of rare earth metals, up to 0.01% Ca, up to 0.01% Mg, up to 0.01% B, ______________________________________and the balance Ni and incidental impurities, wherein the Fe content and the Nb content are defined so as to satisfy the following formula (a):Fe(%).gtoreq.4.times.Nb(%)+12.

Abstract: A refractory protective block protects heat exchange means connecting tubes to fins. The refractory protective block has an inside complementary shape corresponding to the surface shape of the heat exchange means and the refractory protective block is provided with recesses into which projections formed on the tubes are fitted and received. A pair of projections formed on the two adjacent tubes in the heat exchange means are arranged so as to confront each other. The refractory protective block has a high durability which does not break even when heat exchange means expand more than the refractory block at the time of the repetition of heating and cooling and which enable the dispersion of strain at the time of the repetition of expansion and contraction.

Abstract: A heat-insulating lining on heat exchanger surfaces for reducing the heat flow at the cooling surfaces of a medium- or high-pressure heat exchanger, which comprises a tube-web-tube wall. Corrosion resistant fastening pins are arranged in a weld area on the webs of the cooling surface. A ceramic fiber material is arranged as a heatinsulating material on both sides of the webs up to the level of the outside of the tubes of the tube wall, and segments of a ceramic moleskin mat, which are held by fastening pins and fastening washers, are arranged above it on both sides. An expanded metal, which is protected by a refractory material with good corrosion resistance, is additionally arranged at one or both edge zones and at the locations of the joints of the moleskin mat segments.

Abstract: A deflector means having a trapezoidal cross section for reducing erosion of heat exchanger tubes caused by a flowing, particle-laden combustion gas produced in a fossil fuel-fired boiler, and a draft loss reduction means for use in connection with the deflector means. The deflector means preferably is attached to heat exchange tubes in a first row of a tube bank so as to precondition the combustion gas flow. The draft loss reduction means preferably is affixed to heat exchange tubes in a second row of a tube bank in order to reduce draft loss typically caused when combustion gas flows around heat exchange tubes.

Abstract: The present invention relates to a refractory shield for protecting a superheater tube against fluid attack comprising first and second partial-tubes, each partial-tube having a C-shaped cross-section, the C-shaped cross section defining first and second ends; wherein the ends of the partial-tubes are opposably engaged, and wherein the partial-tubes comprise means for preventing radial movement of the first partial-tube relative to the second partial-tube.

Abstract: A tube and tube shield assembly comprising a cylindrical tube having an exterior surface and a locking block extending radially outwardly from the exterior surface, and a tube shield mounted on the tube immediately above the locking block. The tube shield includes a semi-cylindrical body portion having a radius substantially equal to that of the tube, and a tongue extending outwardly from an end or a side edge of the body portion and inserted through an aperture in the locking block. Retaining straps retain the body portion in tight engagement with the tube. Preferably, there are two retaining straps, which are inset from the first and second end edges, respectively, of the body portion, each of the retaining straps having ends overlapping the side edges of the body portion. The tongue is bent away from the tube to lock the tongue, and consequently the attached body portion, in place. In an alternate embodiment, tongues can be provided at both end edges for engagements with a pair of spaced locking blocks.

Abstract: A protective wall structure for protecting boiler tubing in facilities using refuse as a fuel source to produce steam for electrical power generation. The protective wall structure includes an array of shielding tiles, heat transfer bonding material, and elongated compressible material. The shielding tiles include a front surface facing the interior combustion zone of the facility, a rear surface facing the boiler tubes, and a plurality of sidewall surfaces. The heat transfer bonding material is positioned between the boiler tubes and the rear surfaces of the shielding tiles to permit heat transfer and create a bond between the boiler tubes and the shielding tiles. The elongated compressible material is positioned between the sidewall perimeter surfaces of adjacent shielding tiles to provide an expansion joint. This permits relative expansion between adjacent shielding tiles without cracking upon an increase in temperature in the interior combustion zone.

Abstract: A tube and tube shield assembly comprises a cylindrical tube having a lug extending radially therefrom and a tube shield. The tube shield includes a semi-cylindrical shield member having a diameter substantially equal to that of the tube, the shield member having a slot formed therein for receiving the lug, and a retainer for retaining the shield member in engagement around the tube. The tube shield has an upper end and a lower end, and the slot is formed either extending inwardly of the lower end, for use with vertically-oriented tubes, or the tube shield has the slot formed intermediate its ends, for use with horizontally-oriented tubes. The retainer can comprise at least two U-shaped straps, each of the straps having opposed ends attached, for example by welding, to the tube shield.

Abstract: A tube shield for protecting the tubes of heat exchangers, such as boilers and condensers, from hostile elements. The tube shield includes an axially elongated arcuate protector member and a plurality of spring clips secured to the axial free edges of the protector member at spaced locations along the length of the protector member. The spring clips are sized and configured such that they splay outwardly as the protector member is pressed downwardly over an associated tube to pass the maximum diameter of the tube and thereafter move inwardly in a spring biased manner to bitingly engage the exposed portion of the tube to preclude inadvertent separation of the protector from the tube.

Abstract: A tube shield and a method of providing shielding for tubes. The tube shield is provided in a cane or J-configuration, including an upper hook portion and a sheet portion, and a U or drape configuration, including an upper hook portion and a pair of spaced sheet portions extending downwardly from the hook portion in a parallel spaced relation. In both shields, spacer means are provided in the form of embossed protuberances of generally hemispherical configuration extending outwardly from the general plane of the sheet portions at spaced locations on the sheet portions. In the assembled relation of the shields in a tube installation, cane shields are hooked over the outboard rows of tubes and drape shields are hooked over the inboard rows of tube with the protuberances on the sheet portions of the tubes maintaining the sheet portions of the adjacent shields in positive spaced relation.

Abstract: A method for increasing the reliability and remaining useful life of a system of boiler tubes. The present condition of boiler tubes is ascertained and a temperature profile is developed. Additional operating parameters are obtained and used to model the tube system. The model is manipulated to predict a modification which will cause increased tube system life and reliability. The tubes are modified according to the model.

Abstract: Device for the protection of boiler screens, in particular for garbage incinerators, and manufacturing process for this device. Device for protection of screens used for heat-recovery boilers, composed of vertical tubes 1, 14 joined together using welded ribs (17) installed between fireproof bricks and fitted with means for fastening them, these tubes being equipped with vertical auxiliary fastening ribs 2, 11; 3, 13 forming an angle of between 30.degree. and 60.degree. with the plane of the ribs 17, and made discontinuous at intervals on the vertical sections of the tubes. A first series of bricks in fastened on the upper portion of the auxiliary ribs. A second series of bricks 6, 18, alternating with the bricks of the first series, has a general dovetail shape and is fixed in position between recesses 7, 8 in the bricks of the first series. Process for the manufacture of this device.

Abstract: A process for producing hydrogen cyanide which comprises reacting methane or a gas containing methane as a main component, ammonia and an oxygen-containing gas in the presence of a platinum-containing catalyst, wherein the reaction gases are quenched by using an indirect heat-exchanger, preferably an indirect heat-exchanger made of a nickel alloy having an iron content of not more than 4.0% by weight, without quenching them directly with water.

Abstract: A condensing heating module for heating a fluid and adapted for use with a radiant infrared burner. The heat exchanger within the module is spirally disposed about a central burner cavity and has a fluid flow passage of serpentine shape formed within its wall. The upper and lower surfaces of the module, together with the spiral wall of the heat exchanger, form a spiral condensing flue leading from the central burner cavity to an external flue. Those portions of the spiral heat exchanger wall and the module upper and lower surfaces which are exposed to direct radiation from the burner are formed of a corrosion resistant steel, while the remainder of the surfaces and wall are formed of carbon steel to which has been laminated a layer of polypropylene such that the polypropylene layer will be exposed to the flue gas and condensate environment and provide corrosion protection to the carbon steel.

Abstract: A system for protecting a heat-recovery boiler screen, in particular for waste incineration furnaces, said screen being formed by vertical tubes (1, 2) interconnected by welded fixing fins (3, 4, 5) disposed in cavities in refractory bricks (7) and provided with hooking means for refractory bricks. The screen includes windows (6) going through the fixing fins, each brick is provided with at least one hooking lug (8) whose axis is at an angle to the horizontal such that each brick is held suspended by its own weight in one or more windows of the corresponding screen, and the gaps remaining between the bricks, their hooking lugs, and the screen are filled with a refractory cement (9).

Abstract: A heat exchange element in the form of a tube, lies in a particulate laden gas flow and is charged with an electrostatic charge of the same polarity as an electrostatic charge on particles suspended in the gas flow, in order to prevent accumulation on any part of the heat exchange element which would interfere with the rate at which thermal energy can be transferred through the heat exchange element or restrict flow of gas through the heat exchanger.

Abstract: A process for the gasification of coal to produce synthesis gas is disclosed, the process being characterized by passage of product gas stream containing sticky or molten particles upward from the gasification zone and quenching of the product gas stream and particles in a quench zone coated or lined internally with boron nitride.

Abstract: A process for the gasification of coal to produce synthesis gas is disclosed, the process being characterized by passage of product gas stream containing sticky or molten particles upward from the gasification zone and quenching of the product gas stream and particles in a quench zone coated or lined internally with silicon carbide.

Abstract: A cracking furnace for naphtha and other hydrocarbons or, in general, for the rapid heating of a fluid feed stack has one or more tubular elements satisfying the following conditions: d.sub.h 32 F/U.ltoreq.40mm, and D/d.gtoreq.2, wherein: d.sub.h =the hydraulic diameter of the flow passage defined as the ratio of the flow cross-sectional area to the inner peripheral dimension therearound; F=the flow cross-sectional area; U=the inner peripheral dimension of the flow cross section; d=the cross-sectional height of the flow cross section; and D=the width of the flow cross section.

Abstract: A soot blower lance for power generation boilers and the like, particularly for high temperature operation, in locations exposed to radiant heat. The lance is of multi-section tubular construction, with high temperature alloys used in the sections exposed to maximum temperatures. The lance is provided with a thin outer coating of ceramic, such as fused silica and zirconia. Significantly extended operating life is realized, along with significant energy savings from reduced usage of cleaning fluids for cooling purposes.

Abstract: The heat exchanger tube bundle fluid entry area is a region where particular problems can occur because pieces of metallic debris can collect and focus their mass at this low elevation. The metallic debris collected at the bottom of the annular downcomer passage can be swept into the tube bundle, wherein they will impact upon the tube bundle and can cause repture or large amounts of wear to the heat transfer tubes. To prevent this adverse condition, a circumferential row of cylindrical members are positioned peripherally about the entry portion of the tube bundle. These members will have an outside diameter, pitch, and geometric array corresponding to that of the heat tranfer tubes, so as to minimize pressure drop, due to flow across them.

Abstract: Vertical tubes joined to each other by means of welded coupling fins and forming boiler baffles for refuse incinerators are placed between refractory bricks and provided with vertical auxiliary anchoring fins which make an angle of 30.degree. to 60.degree. with the plane of the coupling fins and are interrupted at intervals over vertical sections of the tubes. One portion of the bricks is provided with vertical recesses corresponding to the auxiliary fins over a fraction of their height from the bottom and the other portion of the bricks is provided with vertical recesses up to their full height. The bricks of the first portion are anchored to the top portion of the auxiliary fins and the bricks of the other portion are engaged on these fins above a brick of the first portion.

Abstract: A process for the gasification of coal to product synthesis gas is disclosed, the process being characterized by passage of product gas stream containing sticky or molten particles upward from the gasification zone and quenching of the product gas stream and particles in a quench zone coated or lined internally with titanium diboride.

Abstract: A process for the gasification of coal to produce synthesis gas is disclosed, the process being characterized by passage of product gas stream containing sticky or molten particles upward from the gasification zone and quenching of the product gas stream and particles in a quench zone coated or lined internally with silicon nitride.

Abstract: Straight and arcuately curved superheater tube shields of refractory material comprising a pair of elongated half shields of identical interchangeable interfitting and interlocking size and shape, each half shield having a semicircular sidewall of corresponding straight or arcuate shape of predetermined radius of curvature extending between opposite ends and to inner diametrically opposite inner sides lying in a central plane and the plane of curvature. A number of mating camming portions with inclined camming surfaces are precisely spaced adjacent each of the inner sides so that one of the half shields may be turned end for end relative to and assembled to the other about a correspondingly shaped superheater tube by a relatively short axial movement and engagement of the inclined camming surfaces whereby the half shields are pulled together to close the joints therebetween and interlocked about the superheater tube. A refractory cement may be applied to attach the half shields to the tubes.

Abstract: A heat exchanger having a housing with one or more tubes therein for the transportation of a first fluid through the tubes and a second fluid through the housing and at least partially around the tube or tubes, in which each tube includes two concentric walls with a thin layer or thin layers of a relatively soft material between them applied to the outer surface of the inner wall and to the inner surface of the outer wall.

Abstract: Apparatus to reduce or eliminate fluid bed erosion in fluidized bed combustion boilers by increasing the fire-side tube temperature by adding appropriately dimensioned longitudinal or circumferential fins to the inbed heat exchange tubes in the reactor.

Abstract: A composite tube structure having an inner substrate alloy and an outer, corrosion resistant alloy suitable for use in fluid-bed coal combustion reactors to form a water wall around at least a portion of the periphery of the fluid bed zone. The outer, corrosion resistant alloy centers around a composition of 0.1% carbon, 0.2% silicon, 0.5% manganese, 22% chromium, 3.8% aluminum, 0.4% titanium, 0.05% nitrogen, 0.2% molybdenum, 32% nickel, balance iron.

Abstract: A superheater tube shield of refractory material comprises a pair of elongated half shields of identical interchangeable interlocking size and shape, each half shield having a semi-circular sidewall portion extending between and to diametrically opposite tongue and groove side wall portions which are assembled together about the tubes by axially inserting elongaged tongues into the elongated grooves. Refractory cement may be applied to attach the half sheilds to the tubes.

Abstract: The invention relates to the protection of metal boiler tubes from corrosion and erosion. Accordingly, the invention provides a metal boiler tube whereof at least a selected part of its surface is initially porous and whereof the initially porous surface has been coated with at least one stable metal oxide by the aplication to the porous surface of a solution containing salts or oxides of such metals followed by the conversion of such salts or treatment of such oxides of metals to attach the stable metal oxides to the porous surface.

Abstract: A composite boiler tube has a fireside surface and a water-side surface and comprises a metallic tubular member having an outer surface and an inner surface. One of the metallic surfaces has an efficiency enhancing coating adhered thereto and providing the composite tube with the fireside surface or the waterside surface. A method of enhancing the efficiency of a boiler tube which comprises a metallic tubular member having an outer surface and an inner surface includes the step of applying a coating of efficiency enhancing material adhered to one of the metallic tube member surfaces, thus to produce a composite boiler tube.

Abstract: A device for protecting wear of heat transfer tubes in a fluidized-bed boiler is disclosed. The protective device is applied to a portion of a heat transfer tube which is strongly and exceedingly attacked by fluidized bed materials, so that the considerable decrease in service life of a heat transfer tube due to wear caused by the attack of fluidized bed materials can be avoided.

Abstract: A tubular recuperative heat exchanger (10) is adapted for transferring heat from a hot gas stream having a temperature of 1200 F. flowing over the outside surface of the heat exchange tubes (12) to a cold gas stream flowing therethrough. A turbulator (22) is disposed within each heat exchange tube (12) to improve convective heat exchange. The turbulator (22) is coated with a material having a higher absorptivity than that of the underlying surface of the turbulator. Further, the inside surface (24) of the heat exchange tubes (12) may be coated with a material having a higher emissivity than that of the underlying inside surface of the heat exchange tubes.

Abstract: A boiler tube having a double-tube structure constituted by an inner tube and an outer tube integrated with each other. The inner tube is made of an alloy consisting essentially of, by weight, 0.02 to 0.15% of C, 0.5 to 3.5% of Si, not greater than 2% of Mn, 25 to 40% of Ni, 20.5 to 27% of Cr, 0.5 to 3% of Mo, not greater than 1% of Nb and the balance Fe and having a substantially fully austenite structure. The outer tube is made of an alloy consisting essentially of, by weight, 0.02 to 0.2% of C, not greater than 3.5% of Si, not greater than 2% of Mn, 33 to 45% of Ni, 30 to 40% of Cr and the balance Fe and having a substantially fully austenite structure. The inner tube made of the alloy having the composition specified above exhibits a high resistance to steam oxidation without any reduction in high-temperature strength even at elevated steam temperature, while the outer tube made of the alloy having the composition specified above exhibits a superior resistance to corrosion by coal combustion gas.

Abstract: A pool or spa water heater comprises:(a) a housing containing a combustion chamber,(b) gas burner means associated with the housing to produce hot products of combustion rising in said chamber,(c) a heat exchanger associated with said chamber in the path of said products of combustion to transfer heat to water flowing through said exchanger,(d) said exchanger including inner and outer metal tubes for transferring heat from the outer to the inner tubes and then to water flowing in the inner tube or tubes, said tubes having metal to metal contact,(e) whereby condensation of moisture from said products of combustion on exposed surfaces carried by the outer tubes is reduced.

Abstract: A device for heating air by flue gases in steam boilers and furnaces, comprises a supply flue, sections mating therewith, and a device for protection of heat-exchange tubes against abrasive wear arranged in the flue. Each section comprises heat-exchange tubes attached to tube plates. The device for protection of the heat-exchange tubes against abrasive wear incorporates at least one screen formed by corrugated sheets facing each other and mating along the lines of contact of sheet convex portions, whereby cells are made up.

Abstract: Two types of boilers for generating high pressure steam from gaseous effluents containing abrasive and corrosive solids are provided. Both types of boilers are vertical boilers of the fire-tube type with the gas flowing within the boiler tubes and with the water and steam surrounding the boiler tubes.In one type of boiler according to this invention, the solids-containing gas is downfed through the boiler tubes with the gas emerging from the tubes and impinging on a concave, conical deflector and a convex nose cone located below the deflector. The deflector and nose cone serve to disengage solids from the gas.In the other type of boiler according to the invention, the solids-containing gas first impinges on a baffle plate which serves to disengage solids from the gas. The solids flow down for removal, while the gas flows up the boiler tubes to generate steam.

Abstract: This invention provides zirconium stabilized corrosion-resistant ferritic stainless steels particularly suitable for long-term use at moderate service temperatures in the as-welded condition or following a high temperature anneal.

Abstract: This invention provides two stabilized corrosion-resistant ferritic stainless steels particularly suitable for long term use as tubing in the service environments frequently found in moisture separator reheater and feedwater preheater equipment in the steam supply systems of commercial electrical power generating stations.

Abstract: A waste heat boiler which comprises a water chamber and a water vapor chamber, both surrounded by an opposed pair of tube plates, respectively, and a plurality of double tubes extending across the two chambers. The inner tubes within the double tubes are adapted to pass hot waste gases therethrough, while annular spaces defined between the inner and outer tubes within the double tubes are for directing water to be heated therethrough. At least one end area of the double tubes is of triplicate structure so that thermal stresses generated from thermal expansion of the tube elements may be absorbed effectively.

Abstract: A method of pre-heating feed water for boilers is disclosed which utilizes the exchange of heat between the tube side of a heat-exchanger which contains de-salinated and de-ionized water and the shell side which contains hydrocarbon vapors boiling in the range of 90.degree. to 150.degree. C. The tubes are made of carbon steel with their outer surfaces aluminized.

Abstract: A novel low C-Cr-Mo steel having an excellent weldability and a high erosion-corrosion resistance under wet steam, which consists of, in % by weight, 0.02-0.14% of C, not more than 0.90% of Si, 0.30-0.80% of Mn, 0.70-1.60% of Cr, 0.40-0.70% of Mo and the remainder being susbtantially Fe. This novel steel is a very excellent material for fabricating the portions in the feed-water heater, for example, for a nuclear power generation plant, the portions being used under wet steam condition. The above described weldability and erosion-corrosion resistance can be improved, by additionally adding the second components of Cu, N, or B, the third components of Nb or V or the fourth components of Al, Ti or Zr in the respectively defined amounts.