63results about How to "Solve the problem of easy cracking" patented technology

The invention discloses a method for straightening bending deformation of a crankshaft. The method comprises the following steps of: performing elastic correction on the bent deformed crankshaft by using a straightening tool in a hot state, namely making the crankshaft generate certain reverse bending elastic deformation according to the bending deformation; performing setting treatment on the elastically corrected crankshaft at the temperature of 400+/-10 DEG C; keeping the pressure state of the set crankshaft, and cooling the crankshaft to room temperature by air; and unloading the crankshaft, and performing stress removal aging treatment on the unloaded crankshaft at the temperature of 300+/-10 DEG C. The invention also discloses a tool for straightening bending deformation of the crankshaft. The crankshaft is elastically corrected through the special straightening tool, the problems that the large crankshaft is difficult to straighten and easy to crack in the prior art are solved,and the straightening process is simple, convenient, safe and reliable.

The invention discloses a high-performance two-component polyurethane external thermal insulation anti-crack leveling mortar which is prepared by mixing a component A and a component B, wherein the component A comprises the following compositions in percentage by weight: 60 to 80 percent of gelled materials, 20 to 30 percent of aggregates and 0 to 10 percent of functional admixtures; and the component B is water repellents. The construction method of the mortar comprises the following steps: mixing the component A and the component B; adding an appropriate amount of water in the obtained mixture; and uniformly stirring the obtained object until the obtained object reaches the consistence suitable for mechanical spraying or manual construction, namely, the obtained object can be subject to mechanical spraying or manual construction. The external thermal insulation anti-crack leveling mortar of the invention has the advantages of low water absorption rate, low modular ratio, high caking property and stable performance; and the interface processing carried out on a polyurethane insulation coating can be omitted, and the quality problems that a polyurethane external thermal insulation system is easy to produce crazes and hollowing, and the like can be solved.

The invention discloses a method for producing a ladle joint material by utilizing waste corundum bricks. The method comprises the following steps of: conveying 35 parts of 1-8 mm waste corundum brick granules, 35 parts of 0.1-8 mm white fused alumina granules, 10 parts of powder materials, 10 parts of alumina powder, 3 parts of fused magnesia powder, 1 part of silica powder and 6 parts of calcium aluminate cement into a stirrer, and fully stirring to obtain the ladle joint material finished product. The obtained ladle joint material finished product has the physical and chemical indexes as follows: after the ladle joint material is dried at the temperature of 110 DEG C for 24 hours, the compressive strength is more than 40MPa, and the flexural strength is more than 5MPa; and after the ladle joint material is sintered at the temperature of 1550 DEG C for 24 hours, the bulk density is not less than 3.0 g/cm<3>, the flexural strength is more than 12MPa, and the linear change rate is +/-0.5%. In the method disclosed by the invention, 1/3 of waste corundum brick granules are used as aggregates, thus the cost of the ladle joint material and the cost of per ton of steel are greatly lowered; and calcium aluminate cement is used for binding, and alumina, fused magnesia and silica are used as media, thus the problem that the recovered waste corundum brick granules are easy to crack when used in high-grade pouring materials is solved, and the requirements for safety and durability of the ladle are achieved.

The invention discloses a preparation method of a 2050 aluminium-lithium alloy fine-grain plate. The preparation method comprises the steps: firstly carrying out solid solution and water quenching atthe temperature of 450-550 DEG C; then carrying out rolling predeformation under room temperature, wherein the total predeformation amount is 35-55%; then carrying out overaging treatment for 24-60 hours at the temperature of 350-450 DEG C; then after preserving heat for 1-3 hours at the temperature of 150-250 DEG C, carrying out rolling deformation on the plate, wherein the total deformation amount is 80-96% and the pass deformation amount is 10-30%; finally, carrying out recrystallization and annealing in a salt bathing furnace for 1-60 minutes at the temperature of 450-550 DEG C. The preparation method disclosed by the invention has the beneficial effects that rolling predeformation with large deformation amount is adopted, and overaging and intermediate annealing are combined, so that92% low-temperature rolling deformation is realized in aluminium alloy with poor low-temperature plasticity, the deformation energy storage of the alloy is fully preserved, simultaneously the crackingof the plate is effectively inhibited, the grain refinement is realized, and the 2050 alloy plate with the grain size being 8-10mu m and without cracking is prepared.

The invention discloses high-ductility waterproof anti-crack composite mortar and a mixing method and a construction method thereof. The mortar is prepared from cement, fly ash, mineral powder, lime powder, silica fume, a primary admixture, quartz sand, redispersible latex powder, a waterproof agent, polyvinyl alcohol powder, a water reducing agent, an epoxy emulsion, a curing agent, hydroxypropylmethyl cellulose, an expanding agent and polyvinyl alcohol fibers. According to the disclosed mixing method, a reasonable feeding sequence is adopted to obtain a uniform mortar material. The construction method provided by the invention adopts construction steps suitable for the mortar provided by the invention for different building environments. The composite mortar prepared by the invention has the advantages of water resistance, crack resistance, high ductility, high cohesiveness, seepage resistance, harmful ion erosion resistance, no shrinkage, simplicity and convenience in constructionand the like; can be used for rigid waterproof and anti-cracking engineering of building outer walls and toilets, rigid waterproof and anti-cracking engineering of places such as elevator shafts, roofs and basements, and hydrological engineering such as ports and wharfs which need to be waterproof, anti-cracking and corrosion-resistant.

The invention relates to the technical field of bridge construction, in particular to a concrete arch rib construction method. Divide the arch rib to be constructed into multiple sections arranged at intervals, build formwork on the bridge deck, pour the sections in sequence based on the formwork and reserve separation grooves between adjacent sections, and after all the sections are poured, the Concrete is filled in the separation groove to connect all the segments as a whole to form arch ribs. The present invention minimizes the stress generated during the pouring construction of the arch ribs through segmental construction, avoids the deformation of the arch ribs caused by stress release, ensures the requirements of the arch rib line shape, and at the same time, the arch ribs are reasonably segmented The construction efficiency is improved, the construction period is saved, and the difficult problem that the arch foot concrete is easy to crack is solved.

The invention provides a concrete member and steel support H-shaped embedded connection joint. The concrete member and steel support H-shaped embedded connection joint is arranged between beams and columns of a house. The concrete member and steel support H-shaped embedded connection joint comprises concrete member parts and connection joint parts, wherein each concrete member part comprises concrete beam inner longitudinal bars, concrete beam inner stirrups, concrete column inner longitudinal bars, concrete column inner stirrups, a first steel plate and a second steel plate; each connection joint part comprises a first support connection joint plate, a second support connection joint plate and steel supports; and both ends of each support steel are respectively and mutually connected with the connection joint parts. The concrete member and steel support H-shaped embedded connection joint is characterized in that the corresponding concrete member part also comprises third steel plates. The third steel plates are located between the first steel plate and the second steel plate; one ends of the third steel plates are connected with the first steel plate; and the other ends of the third steel plates are connected with the second steel plate.

The invention provides a high-crack-resistance damping coating. The high-crack-resistance damping coating comprises the following raw materials in parts by weight: 290 to 310 parts of an acrylic acid waterproof emulsion, 95 t 105 parts of an anti-rust emulsion, 45 to 55 parts of a plasticized acrylic acid emulsion, 13 to 17 parts of a film-forming aid, 90 to 110 parts of functional fillers and 45 to 55 parts of corrosion-resistant fillers. The damping coating has high flexibility, impact resistance and high stone crash resistance, and solves the problem that the profile 90-degree transitional coating is susceptible to cracking.

The invention discloses a large-section U-shaped earth pressure balance shield tunnel construction method based on a U-shaped shield tunneling machine. The large-section U-shaped earth pressure balance shield tunnel construction method comprises the following steps that 1, an opencut tunnel counter-force structure shield launching device is arranged, and the end is reinforced through a large pipeshed in the tunnel entering direction; 2, a launching base is arranged on a bottom plate structure, three first guide rails are arranged on the launching base to serve as a shield tunneling machine guiding rail, three second guide rails are laid in a tunnel portal pilot tunnel, the first guide rails and the second guide rails are connected and located at the connecting position of the shield tailof the shield tunneling machine and a medium shield, and a shield tail welding groove is formed in the launching base; and 3, an opencut tunnel reinforcing section structure is arranged to provide counterforce for the shield tunneling machine. On the basis of the U-shaped shield tunneling machine, a complete set of technologies, including the opencut tunnel counter-force structure shield launchingtechnology, the shield tunneling parameter control technology, the large-section U-shaped shield segment splicing technology and the muck improvement technology, of large-section U-shaped shield construction is formed.

The invention relates to a preparation method of graphene composite silicon-carbon-nitrogen precursor ceramics, wherein the preparation method includes the following steps: (1) stirring polysilazane (PSZ) and graphene evenly in an N2 atmosphere to obtain a mixed solution; (2) rising the temperature of the mixed solution obtained by the step (1) with the heating rate of 3-5 DEG C/min from room temperature to 300-800 DEG C, and solidifying for 1-8 h; (3) carrying out crushing ball milling of the material solidified in the step (2) in a vibrating ball mill, and allowing the powder to pass througha 100-200 mesh sieve; (4) carrying out press molding of the powder obtained in the step (3) under the pressure of 5 MPa-15 MPa, carrying out cold isostatic pressing, and under the pressure of 150-250MPa, maintaining the pressure for 200-400 s to obtain a green body; and (5) carrying out heat treatment of the green body obtained in the step (4) under N2 atmosphere protection at the temperature of1000 DEG C-1300 DEG C, carrying out heat preservation for 2 h-6 h, and thus obtaining the product. The graphene material is introduced in the preparation process of a precursor, a real part and a virtual part of the relative complex dielectric constant of the ceramic material obtained by heat treatment are increased, the loss factor is increased and the reflection loss of the material is improved.

The invention discloses a safe-to-use sliding table saw and a safety use method, and belongs to the field of woodworking machinery. The safe-to-use sliding table saw comprises a sliding table saw body, a lifting assembly and a saw blade shield, wherein the sliding table saw body comprises a processing table for placing wood, a rotary saw blade fixedly connected with the processing table and a sawdust collecting assembly fixedly arranged at one end of the rotary saw blade; the lifting assembly performs up-and-down linear motion on one side of the rotary saw blade; the saw blade shield comprisesa shield body, an elastic assembly and a rolling assembly; the shield body is fixedly connected with the lifting assembly through the elastic assembly; the shield body abuts against timber through the rolling assembly; and a humidifying assembly is arranged in the shield body. According to the safe-to-use sliding table saw and the safety use method, an existing sawdust recycling function is reserved, the resistance generated when the shield body abuts against the timber is reduced through the rolling assembly, the abutting between the shield body and the timber is achieved, the safety of workers in misoperation is improved, and the probability of fire is reduced by humidifying the timber and the rotary saw blade through the humidifying assembly.

The invention discloses a gamma'phase pre-adjusting plasticizing production process of a high-performance high-temperature alloy, and belongs to the technical field of material processing. The gamma 'phase pre-adjusting plasticizing production process comprises the following preparation steps: 1, smelting is performed to prepare a cast ingot to form a fine-grain homogeneous bar after multi-heating forging; 2, before the bar is forged in a two-phase region, when the heating number forging deformation is higher than the critical cracking deformation, the bar is treated through the gamma'phase pre-adjusting plasticizing technology so as to improve the critical cracking deformation, gamma 'phase pre-adjusting plasticizing adjusts the temperature of the bar subjected to two-phase region forging to be the forging temperature Td, heat preservation is conducted for 2-12 h, then the temperature is reduced to 800-1000 DEG C at the speed of 5-50 DEG C/min, and heat preservation is conducted for 3-12 hours; and 3, the cast ingot or the bar billet obtained in the second step is heated to the forging temperature Td again, heat preservation is conducted, the cast ingot or the bar billet is taken out of a furnace and forged, and a homogeneous bar billet is obtained after multiple times of forging. The hot working high-temperature plasticity of the high-temperature alloy is improved.

The invention discloses recycled asphalt concrete. The recycled asphalt concrete comprises the following components in parts by weight: 38-42 parts of coarse aggregates, 45-55 parts of an old asphaltmixture, 3-5 parts of iron ore powder, 1.2-2.5 parts of asphalt and 2-3.5 parts of a regenerating agent. The invention further provides a preparation method of the recycled asphalt concrete. The preparation method comprises the following steps: (1) preparing a recycling agent; (2) preparing a recycled asphalt mixture; and (3) sequentially adding the coarse aggregates and the iron ore powder into the recycled asphalt mixture prepared in the step (2), and carrying out heating and stirring to obtain the recycled asphalt concrete. According to the recycled asphalt concrete provided by the invention, the problem that a regenerated asphalt mixture cracks easily is effectively solved while the utilization rate of the highly old asphalt mixture is considered, so that the recycled asphalt concreteprovided by the invention can be applied to paving high-grade pavements such as fast roads, main trunk roads and the like.

The invention provides a preparation method of a rare earth ion doped ITO target material, and belongs to the field of ITO target materials. The powder of the ITO target material is prepared through the steps of powder vacuum feeding, powder coarse grinding, powder accurate grinding, powder nanoscale sanding, slurry glue preparation, spray granulation and mixing and sieving, then dry pressing and cold isostatic pressing forming, biscuit turning, sintering, machining and binding detection are conducted, and the rare earth oxide powder is added, so that the problems that the high-indium-tin-ratio ITO target material is not high in density and easy to crack are solved, the carrier mobility of the film is improved, and the material can be better applied to the solar cell industry.

The invention discloses an anchoringdevice-free prestress high-strength steel stand mesh U-shaped concrete member reinforcing method. The method comprises the following steps that (1) a stretching bed is erected; (2) prestress steel strands are installed; (3) the prestress steel strands are stretched; (4) holes are punched in the bottom of a beam for steel bar planting; (5) U-shaped steel strands are installed; (6) polymer mortar is sprayed to the outer layer; and (7) the ends of the prestress steel strands on the fixed cross beam at the stretching end are cut off, the stretching bed is detached, and reinforcing is completed. No anchoring device is arranged in the stretching bed, the thickness of a reinforcing layer is small, the dead weight is low, the reinforcing layer is good in bonding performance, convenient and fast to construct, excellent in reinforcing effect and high in adaptability, and corner areas are not prone to cracking after reinforment.

The invention relates to an external mould assembly for cold-drawing pipes, comprising a mould seat, the middle part of the mould seat is provided with an axial external mould containing cavity, the front of the external mould containing cavity is the exit of the mould seat; wherein the external moulding containing cavity is internally provided with a front mould and a rear mould, aperture of a rear mould sizing region is larger than the aperture of a front mould sizing region, and a rear mould transition angle of a rear mould transition region is greater than the a front mould transition angle of a front mould transition region. The invention adopts double external mould structure to carry out steel tube empty sinking operation, not only dimensional change of inner hole and wall thickness of target steel tube can be controlled by the external mould, but also the phenomenon that the diameter of the original pipe is sharply reduced can be eliminated, the problem that the target pipe is easy to crack and has high flexibility when in cold-drawing pipe process reinforcement is effectively solved, and the invention has the advantage that structure improvement is simple while mould cost is not increased.

A system and process for preparing zinc oxide film by DC glow plasma CVD is disclosed. Said system is composed of vaccuum reaction chamber, upper and lower gas inlet tubes, insulating base, cooling chamber, upper and lower gas cavities, and upper and lower gas outlet tubes. Its process includes such steps as vacuumizing reaction chamber, heating substrate on the Ta sheet, filling the gas of diethyl (or dimethyl) zinc via upper gas inlet tube, filling CO2 and H2 via lower gas inlet tube, reacting and thermocracking of diethyl (or dimethyl) zinc to deposit zinc oxide film.

The invention discloses a method for rapidly dissolving Laves phase in a deformed high-temperature alloy ingot by pulse current. The method comprises the following steps of carrying out pulse currentexternal field treatment on the deformed high-temperature alloy ingot under the following treatment parameters that the pulse frequency is 25000-35000 Hz, the current density is 1A/mm<2> - 100A/mm<2>.The method has the advantages that the Laves phase in the material can be completely dissolved at a relatively low temperature within an extremely short time, the time is short, the temperature is low, the operation is simple, the energy consumption can be greatly reduced, and the requirements of current industrial green development planning are met; and in addition, the plasticity of the alloy can be improved, the alloy is used for deformed high-temperature alloy treatment, subsequent cogging and forging processes are facilitated, and a new method is provided for preparation of a high-temperature alloy turbine disc.

The invention discloses a preparation method of a graphene/polyvinyl chloride composite material. The preparation method comprises the following steps of 1, preparing modified graphene, 2, preparing awater-based emulsion, 3, preparing modified polyvinyl chloride resin, and 4, preparing the graphene/polyvinyl chloride composite material. The method disclosed by the invention is low in cost, simpleto prepare and easy for industrial batch production, solves the problem that the traditional waterproof material is easy to crack, and utilizes the graphene to be uniformly dispersed in the polyvinylchloride resin to prepare the waterproof corrosion-resistant composite material under the synergistic effect of the graphene and the polyvinyl chloride resin.

The invention discloses a frost crack prevention solar water heater water inlet-outlet pipe which comprises a water inlet-outlet pipe body connected with a water storage tank of a solar water heater, an inflation device, an air cylinder, pressure measurement devices and a display window. An air inlet of the air cylinder is connected with the inflation device through a pipeline, an air outlet of the air cylinder is connected with the water inlet-outlet pipe body of the solar water heater, a pressure limit valve is arranged between the air cylinder and the inflation device, and a control valve is arranged between the air cylinder and the water inlet-outlet pipe body of the solar water heater. One pressure measurement device is arranged on the air cylinder. The other pressure measurement device is arranged at the top end of the water inlet-outlet pipe body, the display device is arranged in a user house, the pressure measurement device at the top end of the water inlet-outlet pipe body is connected with the display device through a guide wire, and when the pressure value on the display device in the user house is equal to the pressure value of the pressure measurement device on the air cylinder, the water inlet-outlet pipe body is filled with air. The frost crack prevention solar water heater water inlet-outlet pipe is ingenious in concept and simple in structure, saves energy, is environmentally friendly and low in production cost, solves the problem that frost crack easily occurs to the solar water heater water inlet (outlet) pipe, and eradicates water waste.