Method of sealing threaded joints and sealing the mixture for its implementation
(57) Abstract:The invention relates to a method of sealing a sealing mixtures of the mating surfaces of parts in machines and units operating in conditions of high temperatures and pressures, and can be used in the joints of gas pipelines of ways, in particular in the exhaust gas engine with automatic weapons. The described method of sealing threaded connections by drawing on the threads sealing mixture with the subsequent collapse of the thread and drying the product, and as a seal applied refractory slurry on the basis of hydrolyzed ethyl silicate and fine-grained filler is pulverized quartz, folding carving produce continuous rotary action and the time of drying at normal temperature is judged on the solidification of the suspension, and use the filler with the residue on the sieve 0063. It also describes the use of the moulding mixture for the formation of ceramic forms upon receipt steel castings investment casting based refractory slurry of hydrolyzed solution of ethyl silicate and fine-grained filler is pulverized quartz as a sealant of resibo the melting of steel, i.e. more than 1500°C), has minimal thermal expansion and conductivity, is not a scarce material and for curing does not require high-temperature drying, which is invalid for weapons due to the reduction of its strength, hardening occurs at normal temperature or, if necessary, speed up the process - no more than 100 - 150oC. 2 C. p. F.-ly, 2 Il. The invention relates to a method of sealing a sealing mixtures of the mating surfaces of parts in machines and units operating in conditions of high temperatures and pressures, and can be used in the joints of gas pipelines of ways, in particular in the exhaust gas engine with automatic weapons.In any automatic weapons are the main source of energy are generated by the combustion in the barrel propellant charge gases having a high temperature and under high pressure. In a typical system based on the principle of exhaust gases in the barrel wall has a vent hole through which the diverted gas. Energy is extracted from the barrel of the powder gases is fed into the engine exhaust type. In such constructions automatic oru what Redi) is difficult, because in this case, heating of the parts of a gas engine and first shafts, which leads to a high peak (erosion) of the gas hole, and subsequently to the destruction of the trunks.To improve erosion resistance trunks, which contributes to the ability of busy shooting mode, known methods of sealing the venting holes by applying pressed reinforced bushings of the refractory metal is tantalum, molybdenum and other materials having a high erosion resistance (sedate, Automatic weapons. The automatic analysis systems (volume IV, part X). Translations from English., 1959, S. 198).However, at the moment of shot due to elastic deformation of the pressed sleeve makes reciprocating movement relative to the stem, resulting in a broken press fits and there are gaps, which breaks the powder gas, causing increased heating and erosion of the barrel. In addition, the press fit bushings complicates its replacement.To speed up and facilitate the replacement of the bushings used in the system shaft-bushing threaded connection, but it requires more reliable tightness increased (as compared with press Posad is to be placed, based on the plastic deformation of the threads of the shaft. When the driving sleeve of her partial coils of a carving crumple turns the shaft, providing the seal and, at the same time tightly Stopera connection. However, this does not guarantee the tightness of the connection at high temperatures and, in addition, when the wear bushing is difficult its removal /eagles P. I. design principles. Reference textbook. M., "engineering", 1977, vol. 3, S. 146/.The closest creature to the present method of sealing threaded connections, operating at high temperatures, are the methods based on the application of the threads sealing mixture, followed by coagulation of the thread and drying products /eagles P. I. design principles. Reference textbook. M., "engineering", 1977, vol.3, S. 144-145/ - prototype.Known sealing mixture, consisting of a suspension of binder and refractory dry filler - slivopereolla of boron carbide /TU 38-101-594-80/.The closest to the technical nature of the claimed invention are heat-resistant mixture, in the form of siloxane enamels, which are refractory slurry binder is a silicone plastic is., "Engineering", 1977, vol.3, S. 138/ prototype.However, such compositions with increasing temperature lose their sealing properties and do not exclude breakthrough powder gases at temperatures above 800-1000oC due to the burnout of the suspension. In addition, resistant compositions require drying temperature of more than 180oC, which is invalid for some products, in this case for the barrels of automatic weapons due to the decrease of their mechanical strength, violations of coatings and residual thermal strains.The aim of the present invention is to improve the effectiveness of the seal threaded connections screwed detail in the conditions of extremely high temperatures, and the possibility of using them in the gas path of the venting motors automatic weapons, due to the stability of the sealant mixture to high temperatures while no requirements as to temperature drying.This objective is achieved in that in the method of sealing threaded connections by drawing on the threads sealing mixture with the subsequent collapse of the thread and drying of the product as a sealer applied refractory suspension on EfE thread produce continuous rotary action, and dried at normal temperature for a period of time, required for solidification of the suspension, and use the filler with the residue on the sieve N 0063.This goal is achieved by a method for sealing threaded connections as the sealing mixture applied known molding the mixture for the formation of ceramic forms upon receipt steel castings investment casting based refractory slurry of hydrolyzed solution of ethyl silicate and fine-grained filler.Comparative analysis of the proposed solutions with the prototype shows that the inventive method differs from the known application of the hydrolyzed solution of ethyl silicate, which is a mixture of a binder - organosilicon compounds, a higher order than in the original ethyl silicate, powdered filler with the residue on the sieve N 0063, and drying refractory composition is carried out at normal temperature for the time required for solidification of the suspension.In addition, in the method of sealing a threaded connection as the sealing mixture is first applied used for the preparation of molds forming a mixture that meets the criterion of "novelty" and "significant about the I manufacture of molds, meets the requirements listed above: withstands high temperatures (the melting point of the steel, i.e., more than 1500oC) has minimal thermal expansion and conductivity, is not a scarce material and the main thing - to solidification does not require high-temperature drying (hardening occurs at normal temperature or, if necessary, speed up the process - no more than 100-150oC).In Fig. 1 shows the General scheme of the gas exhaust system of the engine automatic weapons, and Fig. 2 is a view of a of Fig. 1.The primary components of the gas system of automatic weapons in accordance with Fig. are the barrel 1 is screwed into the exhaust port 2, the sleeve 3. The sleeve is made with a flange 4, between the turns of the sleeve and barrel put plastic layer of hermetic mixture 5.For experimental validation of the sealing mixture for the proposed method were prepared four options.1. Was used suspension consisting of a binding solution of liquid glass density of 1.1 ... 1.3 g/cm3(40% by volume) and fine-grained refractory material is pulverized quartz (60% by volume).3. Siloxane enamel - suspension organosilicon compounds with a powdery filler - Al, Zn (50% by volume).4. The sand used in foundries for making steel castings investment casting - suspension of hydrolyzed ethyl silicate ETS-32 or ETS-40 (30-40% by volume) and fine-grained refractory material is pulverized quartz (70-60% by volume) RTS 3-372-73. Moreover, the quartz is chosen with the residue on the sieve N 0063 according to GOST 9077-59.The mixture was applied to a plate of aluminum alloy and were subjected to drying at 140-160oC for 3 h (the time required for solidification of the mixture), then all the compounds together with plate were placed in the combustion zone of natural gas. After 15...20 min after the start of heat treatment, the first three of the mixture began to swell on the surface began to appear bubbles, converting them into loose foam mass, testified to burn them in a binder material, and the evaporation of water.The hardened molding the mixture remained unchanged even after thermal deformation of the aluminum plate, which corresponded to approximately 650oC.Further molding sytem frozen mixture was subjected to heat treatment at a temperature of more than 1000oC (temperature was determined by the color of the heated metal plate). The mixture is then kept its shape, strength and remained attached to the plate condition that, in particular, complies with the conditions of its possible application in the exhaust gas engine with automatic weapons and specified requirements.Offer to seal the sand-based refractory slurry of hydrolyzed solution of ethyl silicate ETS-32 or ETS-40 RTM 3-372-73 and fine-grained filler is pulverized quartz as sealing the mixture in the threaded connections in the gas venting paths engines meets the requirements listed above: withstands high temperatures (the melting point of the steel, i.e., more than 1500oC) has minimal thermal expansion and conductivity, is not a scarce material and the main thing - to solidification does not require high-temperature drying (hardening occurs at normal temperature or, if necessary, speed up the process - at 100-150oC). In addition, as the filler is chosen quartz sieve residue N 0063, i.e. with the grain not more than 0,05-0,06 mm of the Use of larger change smaller grain can result in incomplete filling of the troughs of the thread due to the reduced density of the mixture, which increases the displacement of the troughs when tightening.Below is a specific example of implementation of the proposed method.Almost bushing tighten as follows. First sleeve 3 without sealing thread sbencivu to tight contact with the support surface of the barrel 1. Note the position of the flange 4 relative to the trunk. The "0" position (Fig. 2). After that skimmed the threaded surface of the sleeve and the gas discharge port 2 is applied molding the mixture 5. When this is used, given the consistency of the grease, the driving sleeve rotational action, with the aim of gradual and more complete penetration of the suspension into the spaces between the turns of the thread. Wrap the sleeve and the grain size determines the force of the collapse. Pets at screwing up the maximum negovorit sleeve relative position svininih with puff sleeves without sealing gap angle (position "1", Fig. 2) defined
< / BR>where k is a correction factor for the grain size of the filler is equal to 1.0. ..1,1;
S - the maximum grain size of the refractory filler;
h - step thread connection;
- the maximum permissible angle of negovorite sleeve.This angle op the I grain size of the filler, should not affect the accuracy of relative position of the connected parts.After screwing the excess suspension from the external and internal surfaces of the barrel is removed and drying at normal temperature for the time required for solidification of the suspension, but not less than 3 hours To speed up the drying process can be carried out at 100-150oC, without affecting the physical characteristics of the material of the barrel.After drying the butt sleeve is processed flush with the outer surface of the barrel.Use well-known in the foundry production for steel castings investment casting sand-based refractory slurry of hydrolyzed solution of ethyl silicate and powdered quartz as a seal threaded connections allowed due to its high heat resistance, with a minimum coefficient of thermal expansion and thermal conductivity, and most importantly the lack of requirements to high temperature drying, which is not valid for shafts due to the decrease of their mechanical strength, violations of coatings and residual thermal strains, applying it to harden threaded connections in detail the gas is Platania threaded connections by drawing on the threads sealing mixture with the subsequent collapse of the thread and drying, characterized in that the sealing mixture of refractory suspension on the basis of the hydrolyzed solution of ethyl silicate and fine-grained filler is pulverized quartz, folding carving produce continuous rotary action, and dried at normal temperature for the time required for solidification of the suspension, and use the filler with the residue on the sieve 0063.2. The application of the moulding mixture for the formation of ceramic forms upon receipt steel castings investment casting based refractory slurry of hydrolyzed solution of ethyl silicate and fine-grained filler is pulverized quartz as the sealing mixture screw connections.
FIELD: thermal isolation, in particular heat-retention coating for constructive elements, electric equipment, and electric furnace.
SUBSTANCE: claimed composition contains (mass %): silicium 65-67; potassium 3-5; calcium 11-16; titanium 8-13; chromium 2.0-3.5; iron 1.5-2.6; cobalt 0.2-0.4, and zinc 0.03-0.06.
EFFECT: coating of improved heat resistance without losses of physicochemical properties.
3 ex, 1 tbl
SUBSTANCE: invention relates to refractory compositions for gluing graphite-containing articles to metal and can be used in metallurgy, in particular in electrolyzers for imbedding cathode rods into bottom blocks. Composition is constituted by filler including graphite and thermal anthracite, binder containing coal-tar pitch with phenol-formaldehyde resin and curing agent, said filler further containing gray iron in the form of cuttings 0.1 to 1.6 mm in size and including also some amounts of phosphorus and silicon (0.8-1.6 and 2.5-3.6%, respectively, on the weight of gray iron) and said pitch additionally containing methylnaphthalene. Total composition of ingredients is the following, wt %: gray iron 60-70, graphite/thermal anthracite fraction up to 0.2 mm, 8-12, and binder 22-28; and, more specifically: coal-tar pitch 11-21, methylnaphthalene 2-4, phenol-formaldehyde resin 4.3-6.7, and curing agent 0.3-0.7.
EFFECT: reduced bottom voltage drop and increased wear resistance of bottom block due improved physicochemical properties of composition.
FIELD: aerospace industry, mechanical engineering, ship building and construction industry.
SUBSTANCE: fire-fighting material has outer fibrous layer and layer, which swells upon emergency heating. According to one embodiment, fibrous layer is made in the form of knitted fabric of stretchable material manufactured from inorganic threads with melting temperature exceeding 1,150°C. According to another embodiment, fibrous layer is made from stretchable textile or knitted material manufactured from complex thread composed of inorganic filament and filament destructed under thermal action of temperature ranging between temperature value exceeding maximal admissible temperature, at which article to be protected is designed to operate, to temperature value of 1,050°C. These threads may be twisted, or readily destructed thread may be arranged along axis of complex thread and stretchable thread may be wound thereon. In both cases, swelling layer is applied to textile material fabricated from glass or basalt threads non-shrinkable at temperature of 450-1,050ºC and applied to article to be protected. Fire-fighting swelling material may be further provided with heat-insulating mat placed onto article to be protected, made from thermally stable glass or basalt filaments and provided with sheathing. Material has insignificant smoke release and may be applied onto flat and flexible articles of small diameter.
EFFECT: increased fire-fighting capacity and reduced fire penetration allowing articles to be effectively protected from emergency fire, and wide range of fields of application.
13 cl, 4 dwg, 2 tbl, 4 ex
FIELD: building materials, particularly fire-proofing compositions of mortars, concrete or artificial stone.
SUBSTANCE: fireproofing material adapted to protect building structures formed of concrete or prestressed concrete, namely tunnel structure is formed as panels or sprayed hardened coatings. The coatings are obtained by applying hydraulically hardened composition comprising alumina cement. The alumina cement may be mixed with Portland cement, fillers and, if necessary, fibers, cure accelerators, cure retarders, plasticizers and foam generators. The hardened material comprises ettringite in amount of less than 5% by weight. The composition comprises 50-200 part by weight of alumina cement and 10-250 parts by weight of xonotlite. The xonotlite is used as spherical particles with felted structure in uncured state.
EFFECT: increased ability of concrete structure protection against fire, possibility to use the material for tunnel protection, reduced humans harm in case of fire.
10 cl, 2 ex, 2 tbl, 5 dwg