52results about How to "Change stress state" patented technology

The invention relates to a laser cladding composite repair manufacturing method. The method comprises the steps as follows: step 1, laser cleaning; step 2, laser preheating: continuously irradiating the surface of a to-be-repaired workpiece by a laser unit to preheat the to-be-repaired workpiece, marking emergent laser of the laser unit as preheating laser, wherein the spot shape of the preheatinglaser is round or rectangular, the area of preheating spots is 6 mm<2>-20 mm<2> and the scanning speed of the preheating laser spots is 8 mm/s-20 mm/s; step 3, laser cladding: irradiating the preheated to-be-repaired workpiece by cladding laser, wherein the spot shape, spot area and scanning speed of cladding laser are identical with those of the preheating laser; step 4, machining. The inventionalso relates to an application of the laser cladding composite repair manufacturing method. The method can be applied to repair manufacturing of high-carbon steel workpieces and high-alloy steel workpieces; laser is used as machining means, so that the method is clean, efficient, green and environmentally friendly.

The invention relates to a mine vehicle axle wheel reductor planetary gear and a manufacture method thereof. The manufacture method comprises the following processing steps of: (1) forging to obtain a gear ring; (2) roughly turning; (3) carrying out preheat treatment; (4) finely turning; (5) carrying out ultrasonic flaw detection; (6) hobbing; (7) boring a plurality of oilholes in the wall of a planet wheel inner hole in the middle of the gear ring along the radial direction of the planet wheel inner hole; (8) carburizing for heat treatment; (9) performing plain grinding on two end faces of the gear ring to the required size and then grinding the planet wheel inner hole of the gear ring to the required size; (10) grinding the gear; (11) carrying out magnetic powder inspection; (12) strengthening shot peening at gear root; and (13) carrying out manganese phosphating. The planetary gear produced by adopting the manufacture method, disclosed by the invention has the advantages that the contact fatigue strength is better, the reliability is greatly enhanced and the service life is greatly prolonged; and according to the manufacture method provided by the invention, shot peening strengthening is adopted in processing the gear root, and the stress state of the gear root is changed, so that the gear root bending strength of the planetary gear is remarkably enhanced, the strength of the planetary gear is enhanced and the service life of the planetary gear is prolonged.

The invention discloses a gas pipe corrosion defect under-pressure repair method. The gas pipe corrosion defect under-pressure repair method comprises performing surface cleaning on the pipe repair position; filling the pipe perforation leakage position or the outer surface corrosion position with a repairing agent; brushing the epoxy resin primer at the pipe surface position which needs to be wrapped, wherein the thickness of the epoxy resin primer is not less than 0.2 mm; enabling a carbon fiber band to wind the epoxy resin primer brushed pipe surface in a spiral mode, wherein the carbon fiber band winds the first to third layer, a special adhesive is bonded between the layers, and the drum rolling is adopted in the process of winding of the carbon fiber band to avoid the interlayer bulge; brushing the anticorrosive paint at the carbon fiber band wrapping position of the pipe surface. According to the gas pipe corrosion defect under-pressure repair method, the defects of the traditional repair method are overcome; the pipe corrosion and perforation defects are repaired in the running state of a gas pipe, the stress state of the pipe is not changed, the flame operation is not required, and accordingly the potential safety hazard is avoided and the service life is long; the stop operation is not required and accordingly the continuous production is ensured.

The invention relates to a plate incremental forming device based on overlaid double-layer auxiliary materials. The plate incremental forming device comprises an upper auxiliary material, a lower auxiliary material and a tool head matched with the upper auxiliary material, and the upper auxiliary material and the lower auxiliary material are arranged on the two sides of a base material. Lubricating layers are arranged between the base material and the upper auxiliary material and between the base material and the lower auxiliary material. The tool head exerts pressure to the upper auxiliary material, so that the upper auxiliary material, the base material and the lower auxiliary material deform. A plate incremental forming method based on the device comprises the steps that 1) the lubricating layers are arranged on the upper surface and the lower surface of the base material and are attached to the upper auxiliary material and the lower auxiliary material, and a piled material is obtained; 2) the edge of the piled material is clamped and fixed, and processing is carried through the tool head; and 3) and the piled material is taken down, all the layers are separated, and the processed material is obtained. Compared with the prior art, it can be guaranteed that no residual height or processing mark exists on the surface of the base material, and high surface quality is achieved;and according to the plate incremental forming device based on the overlaid double-layer auxiliary materials and the plate incremental forming method, the stress state of base material forming can bechanged, friction force is reduced, and the forming limit of the base material is improved.

The invention discloses a heat treatment method for 20CrNi2Mo steel used in heavy-duty gears. The invention belongs to the technical field of metal material heat treatment. According to the invention, first, 20CrNi2Mo steel is processed through a normalization treatment under a temperature of 930 DEG C for 4 hours; the 20CrNi2Mo steel is processed through a carburization treatment under a temperature of 930 DEG C for 10 hours; then the 20CrNi2Mo steel is processed through an oil medium quenching treatment under a temperature of 830 DEG C for 3 hours; and finally the 20CrNi2Mo steel is processed through a tempering treatment under a temperature of 180 DEG C for 8 hours. According to the invention, a novel heat treatment method is adopted upon the 20CrNi2Mo steel used in heavy-duty gears. With the heat treatment method, performances of the 20CrNi2Mo steel used in heavy-duty gears are good, and deflection can be effectively reduced. Therefore, a basis is established for the expanding of the application field of the 20CrNi2Mo steel.

The invention discloses large-flow-state circumferential inverted arch thin-wall anti-crack concrete and a preparation method thereof. The concrete is prepared from the following components in parts by weight: 220 to 260 parts of ordinary Portland cement, 40 to 50 parts of fly ash, 80 to 100 parts of mineral powder, 20 to 35 parts of silica fume, 700 to 800 parts of coarse aggregate, 300 to 350 parts of modified ceramsite, 600 to 800 parts of fine aggregate, 30 to 50 parts of modified rubber particles, 1.5 to 2.7 parts of thickening agent, 7.2 to 8.9 parts of polycarboxylic acid water reducing agent, 1.6 to 3.1 parts of polypropylene fiber and 3 to 5 parts of expanding agent, and the water-binder ratio is 0.3 to 0.4. According to the large-flow-state circumferential inverted arch thin-wall anti-crack concrete, rigidity gradient change of a vertical structure is achieved, the anti-crack performance in a circumferential structure is good, and inverted arch disengaging and cracking under circumferential constraint are avoided.

The invention discloses pavement concrete for municipal construction engineering. The pavement concrete comprises the following raw materials in parts by weight: 40-50 parts of cement, 10-15 parts ofdiatomite, 5-10 parts of glycerol monostearate, 3-5 parts of sodium monofluorophosphate, 3-5 parts of sodium alginate, 6-8 parts of a water reducing agent, 10-15 parts of an expansion fiber anti-cracking waterproof agent, 3-5 parts of amorphous dodecacalcium heptaaluminate, 4-6 parts of a silane coupling agent, 1-2 parts of vaseline, 4-6 parts of an acrylic emulsion, 1-2 parts of fatty alcohol-polyoxyethylene ether, 1-2 parts of an antifoaming agent and 30-40 parts of water. Compared with the prior art, the pavement concrete has advantages that: by adding the diatomite and the diatomite withinthe particle size range of 3-12 microns, the phenomenon that cracks are found in concrete can be well avoided, and the strength of the concrete is improved; the glycerol monostearate can improve strength of the concrete. In conclusion, the pavement concrete for municipal construction engineering prepared by the scheme has the performance advantages of high toughness, impact resistance, crack resistance, wear resistance, skid resistance and the like.

The invention provides a method for testing the wrinkling performance of a plate based on uniaxial tension of a perforated sample. A circular inner hole is machined in the geometric center of a sampleto change the stress distribution in the uniaxial tension process of a plate, and the wrinkle resistance of a flat plate sample in different stress states is obtained. The sample can be strip-shaped,square or circular. The method specifically comprises the following steps of: (1) determining the shape and size of a sample; (2) analyzing uniaxial tension deformation of the sample by utilizing numerical simulation, and determining the diameter d of an inner hole according to stress distribution and the wrinkling height h; (3) processing the sample according to the shape and the size; (4) stretching the sample at a constant speed v on a universal testing machine; and (5) detecting and recording the wrinkling amount H of the sample. According to the method, by adjusting the size of the innerhole, the wrinkle resistance of the plate can be analyzed within a large dependent variable range, the wrinkle characteristic closer to the actual situation is obtained, no special clamp or device isneeded, and the method is simple, easy to implement and high in repeatability.

The invention relates to a roadway U-shaped support device and method. The roadway U-shaped support device comprises support vault U-shaped steel, support leg U-shaped steel is fixedly connected to the two ends of the support vault U-shaped steel through connecting clamping cables, and a support leg expansion device is arranged at the bottom of the support leg U-shaped steel; the support leg expansion device comprises a lower inner sleeve, an upper outer sleeve, a bundle-shaped composite expansion material cartridge and filling river sand; and the upper outer sleeve sleeves the lower inner sleeve, the bundle-shaped composite expansion material cartridge is arranged in the lower inner sleeve, and the filling river sand is arranged at the top and the bottom of the bundle-shaped composite expansion material cartridge. The overall stress state of the U-shaped support can be effectively improved, load-controllable initial supporting force can be provided for surrounding rock, the function of adapting to surrounding rock deformation is achieved, the column leg structure is good in bending resistance, the column leg strength is high, the structure is simple, the cost is low, the construction process is simple, and the roadway section utilization rate is not affected.

The invention relates to an anchor cable structure and an anchor cable frame beam construction method. The anchor cable structure comprises a guide cap, an anchor cable component, tightening rings, agrouting pipe, expansion rings, an anchorage device, a concrete anchor inclined support and an anchor head, the anchor cable component is divided into a free section and an anchoring section, the topend of the anchor cable free section is arranged on a reinforced concrete frame through the anchorage device, the bottom end of the anchoring section is fixedly connected with the guide cap, and the anchor cable component comprises a steel strand and a steel strand casing pipe. A free section of the steel strand is an oiled coating steel strand, an anchoring section of the steel strand is an exposed steel strand, the steel strand is bound into a steel strand bundle through the evenly-arranged tightening rings, the grouting pipe is arranged in the center of the steel strand bundle, the expansion rings are evenly arranged on the anchoring section of the anchor cable component, the concrete anchor inclined support is arranged at the outer side of the reinforced concrete frame, and the anchorhead is a concrete closed anchor head. A PVC pipe is arranged at the outer side of the free section of the anchor cable component in a sleeving manner, spiral ribs are arranged in frame beams, and gaps are formed between the anchor cable component and the side walls of anchor holes. The slope stress state and the stable state can be changed, and the stability is improved.

The invention provides a PDC drill bit. The PDC drill bit comprises a drill bit body, wherein the drill bit body is provided with a plurality of circumferentially arranged blades, each blade comprisesa first-stage blade, a second-stage blade and a gauge protection part, the first-stage blade wing comprises an inner cone part, a crown arc part, a first outer cone arc part and a first straight linesection part, the second-stage blade wing comprises a second outer cone arc-shaped part and a second straight line section part, the lower end of the first straight line section part is connected with the upper end of the second outer cone arc-shaped part, the inner cone part, the crown arc part, the first outer cone arc part, the first straight line section part, the second outer cone arc part,the second straight line section part and the gauge protection part are each provided with cutting teeth. According to the PDC drill bit, the drilling speed in the oil-gas exploration and developmentwork of a deep well, an ultra-deep well and a large-diameter well section is improved, and the service life of the drill bit is prolonged.

The invention discloses a high-precision zirconium alloy plate rolling method. The method comprises the steps that 1, a zirconium alloy slab is polished until the intra-plate difference is 0.15-0.25 mm; 2, the polished zirconium alloy slab passes through a working roller of a reversible plate rolling mill and is clamped by a hydraulic clamp, and then a hydraulic cylinder provided with a tension sensor is used for making the polished zirconium alloy slab generate and keep tension; and 3, reciprocating tension rolling is carried out and the tension in the rolling process of the zirconium alloy slab is simultaneously controlled to obtain a zirconium alloy plate material. According to the method, the hydraulic cylinder with the tension sensor, a displacement sensor and the plate rolling mill are cooperatively used, the zirconium alloy plate is subjected to reciprocating tension rolling, and the deformation resistance of the working roller and the zirconium alloy plate is reduced by accurately adjusting the tension during rolling, so that the phenomenon of uneven rolling of the zirconium alloy plate and surface scratches and cracks caused by moving and sliding of the zirconium alloy plate are avoided, and the precision of the surface of the zirconium alloy plate is improved.

The invention discloses a coal mine impact ground pressure and harmful gas comprehensive prevention and treatment system and method. Firstly, according to roof lithology and pressure characteristics of a coal mining work face, a target rock layer of horizontal well staged fracturing is determined, according to the target rock stratum and coal seam work face characteristics, a well spacing manner of a horizontal well is determined, the horizontal well is drilled, in the horizontal well, a target rock stratum and a coal seam are subjected to fracturing, through fracturing, the target rock stratum and the coal seam form an inter-communication net-shaped fracture, a ground pump drainage system is built, harmful gas in the coal seam is subjected to pump drainage, the horizontal well is mountedin the target rock stratum, in the horizontal well, the target rock stratum and the coal seam are subjected to fracturing, the inter-communication net-shaped fracture is formed in the target rock stratum and the coal seam, fracturing pressure relief of the target rock stratum is achieved, the stress state of a coal seam roof is changed, happening of an impact ground pressure accident is avoided, and meanwhile, release and pump drainage of harmful gas in the coal seam can be achieved.

The invention belongs to the technical field of geotechnical engineering, and particularly relates to an indoor experiment simulation device and method for geological fault mechanics behaviors of a triaxial tester. According to the indoor experiment simulation device for the geological fault mechanics behaviors of the triaxial tester, a guide groove is formed in a connecting pressing plate, so that water can be led into the surface of a sample; and when the triaxial tester applies pressures in three directions, different stresses can be generated in the three directions by the sample, and a stress state of the sample can be changed by adjusting the pressure in each direction. In an experiment process, the pressure applied to water on the surface of the sample in the guide groove can be adjusted, so that a nature state can be simulated. According to the experiment method disclosed by the invention, a three-direction unequal stress environment can be realized by three groups of pressureheads of the triaxial tester, and a seepage field under a real condition is simulated through the guide groove in the connecting pressing plate, so that indoor experiment simulation of a stress-seepage environment where a real fault is located can be realized.

The invention provides a roll barrel crack controlling method of a roughing working roll, which comprises the steps of: firstly, punching a region with a crack on the surface of a roll, especially on the point end part of the crack; and secondly, measuring and recording the length and the depth of the crack on the surface of the working roll before and after operating by using an ultrasonic flaw detection technology to obtain a speed of crack expansion of the roll in an operating process, and judging that the roll is scraped when the depth of the crack reaches or approaches 50mm. Therefore, the stress state of the point end of the crack is changed, the expanding speed of the online crack of the roughing working roll is effectively controlled, the utilization rate of the working roll is furthest developed, the roll consumption of the roll is reduced, and production and equipment accidents caused by shedding and breakage on the surface of the roll are avoided.

The invention discloses a device and method for preparing a high-density twin crystal material. The device for preparing the high-density twin crystal material comprises a fixing device used for fixing a sample, a transmitting device arranged in front of the sample and a recovery device arranged behind the sample. The fixing device comprises a through hole matched with the size of the outer edge of the sample. The transmitting device comprises a flying sheet which is matched with the shape of the sample and is parallel to the sample, an elastic support used for supporting the flying sheet to move towards the sample and a gun barrel allowing the elastic support to fly. The recovery device comprises a buffer layer arranged on the rearmost portion. A window connected with the sample is arranged behind the sample, and the material of the window is the same as that of the sample. Compared with a traditional gas gun device, the structure is simple, operation is convenient, the stress state generated when the sample is bumped is changed, energy consumption generated in the use process is low, and the metal material with high-density twin crystals can be obtained more easily even though the speed is low. The interior of an obtained product is not damaged, and unfavorable conditions that grains are refined and structures are generated are also avoided.