19results about How to "Reduce temperature stress" patented technology

The invention relates to the field of concrete prefabricated parts, and particularly discloses concrete for prefabricated parts and a preparation method of the concrete. The concrete for the prefabricated part is prepared from 350 to 380 parts of cement, 820 to 860 parts of river sand, 850 to 960 parts of tough epoxy resin modified gravel, 130 to 150 parts of water, 45 to 55 parts of mineral powder, 25 to 35 parts of fly ash, 8.3 to 9.0 parts of a water reducing agent, 5 to 10 parts of a molecular sieve carrier polyamide curing agent, 5 to 10 parts of composite expanded particles and 5 to 10 parts of modified fibers, the preparation method comprises the following steps: uniformly mixing the cement and the river sand, adding the mineral powder and the fly ash, and uniformly mixing to obtain a primary mixture; uniformly mixing the tough epoxy resin modified macadam with a molecular sieve carrier polyamide curing agent, adding the composite expanded particles, and uniformly mixing to obtain a composite material; adding the composite material and the modified fiber into the primary mixture, finally adding water and a water reducing agent, and uniformly mixing to obtain a mixture; and pouring and maintaining to obtain a finished product. The material has the advantages of high strength and difficulty in generating cracks.

The invention belongs to the field of metal powder laser melting additive manufacturing, and discloses a method for eliminating solidification thermal stress through a metal laser melting additive manufacturing technology. The method is realized by adopting SLM equipment and comprises the following steps: step 1, melting laser forming; the SLM equipment comprises a galvanometer, a high-frequency pulse laser, a collimating and beam expanding lens, a melting laser and an infrared thermometer; step 2, starting an infrared thermometer, detecting temperature values of solidified powder at different interval durations by an infrared temperature measurement scanning system at the first layers of scanning forming of the part, and determining the scanning lag duration according to the principle that the temperature of the material is 50 DEG C higher than the recrystallization temperature of the material; and then high-frequency forging laser is started at the same time interval to perform forging treatment, so that the material is subjected to impact forging vibration at the temperature to realize a recrystallization process, and the stress completely disappears. According to the method, the problem that failure is often caused by stress deformation when a selective laser melting method is adopted for manufacturing large-size parts is solved.

The invention relates to the field of wear-resistant materials, and discloses a high-wear-resistance high-chromium cast iron material and a heat treatment process thereof, and the heat treatment process comprises the following steps: taking iron-coated zirconium oxide toughened aluminum oxide ceramic as a reinforcing phase material; the casting is placed in a heat treatment furnace, and the casting is cooled to the room temperature in a graded mode after being heated in the furnace; then carrying out three-stage tempering to obtain a machined part; the cut machined part is subjected to surface cleaning and preheating, and a pretreated machined part is obtained; the preparation method comprises the following steps: uniformly mixing titanium-plated cubic boron nitride powder, graphite, nickel-based alloy powder and a binder, pre-placing the mixture on the surface of a pre-treated workpiece, and preparing a cladding layer by utilizing laser cladding to obtain the high-wear-resistance high-chromium cast iron material. And a cladding layer is prepared from titanium-plated cubic boron nitride powder, graphite and nickel-based alloy powder, and the high-chromium cast iron material with high hardness, high impact toughness and high wear resistance is prepared in a graded cooling and three-stage tempering mode.

The utility model relates to a tube plate structure for a heat exchanger and a winding tube type heat exchanger, and the tube plate structure comprises a heat-conducting tube plate main body which is provided with a first plate surface facing a tube pass medium in the heat exchanger and a second plate surface facing a shell pass medium in the heat exchanger, a plurality of tube holes penetrating through the first plate surface and the second plate surface are formed in the tube plate main body at intervals; an annular groove extending in the circumferential direction is formed in the second plate surface of the tube plate main body, and the annular groove is formed in the periphery of each tube hole; the tube plate structure further comprises an annular check ring which is arranged in the annular groove in the circumferential direction so as to shield a groove opening of the annular groove. A through hole for a shell pass medium to enter the annular groove is formed in the check ring, or / and a gap for the shell pass medium to enter the annular groove is formed between the periphery of the check ring and the corresponding inner wall of the notch in a spaced mode. The tube plate structure disclosed by the utility model can bear a larger temperature difference between a tube pass medium and a shell pass medium.

This invention discloses a seed crystal oxidation structure to prevent oxidation of single-crystal superalloys during directional solidification, aiming to effectively suppress surface oxidation of the seed crystal during directional solidification. To this end, the seed crystal oxidation structure provided by this invention includes a ceramic mold shell, in which a seed crystal is fitted into the seed crystal cavity of the ceramic mold shell. The top of the seed crystal is covered by an alloy spacer, the melting point of which is lower than that of the seed crystal.

The invention belongs to the technical field of medical engineering, and particularly relates to a construction method of an ultra-large-volume concrete structure for a linear accelerator, which comprises concrete raw material selection and mix proportion design, design of a building template supporting and reinforcing system, and crack control measures of the ultra-large-volume concrete structure for the linear accelerator. A building formwork supporting and reinforcing system comprises a wall formwork supporting system, a top plate side formwork supporting system, a top plate formwork supporting system and a method for arranging split bolt joint positions between walls and plates. The building formwork supporting and reinforcing system has the beneficial effects that crack control is conducted on an engineering structure from the whole process of concrete raw materials, additives and the construction technology, and the construction efficiency is improved; the split bolts and the cooling water circulation cooling pipe network enhance the integrity and stability of the wall body and prevent the formwork from expanding, so that rays emitted by the linear accelerator are effectively shielded.

The invention belongs to the technical field of high-temperature energy storage, and discloses a high-temperature storage tank composite foundation for a high underground water level. A layer of inner ring beam outer side annular steel plate is laid on the outer side of an inner ring beam, a fireproof ceramic fiber plate is filled between the height range of the inner ring beam and an outer ring wall, and the outer ring wall is placed on a bearing raft; a sliding layer is arranged between the outer ring wall and the bearing raft, a heat preservation layer adheres to the outer side of the outer ring wall, the waterproof cofferdam and the bearing raft are integrally poured together, a waterproof heat preservation layer and a drainage ditch are arranged in the waterproof cofferdam, the drainage ditch is provided with a water collecting pit, and the two sides of the waterproof heat preservation layer are flashed and fixedly connected with the waterproof cofferdam and the bearing raft respectively. A high ring wall protrusion is arranged at the contact position of the bearing raft and the outer ring wall to serve as a sliding step, a reinforced concrete limiting tenon integrally poured with the sliding step is arranged on the inner side of the outer ring wall above the sliding step, four drainage pipes are evenly arranged on the periphery of the top face of the bearing raft, and a ventilation pipe is buried in the bearing raft. Meanwhile, the functions of water resistance, heat preservation, effective temperature stress release and the like are achieved.

The application discloses a kind of high temperature pressure vessel nozzle temperature self-regulating heat insulation device, including heat bridge and heat insulation layer.Heat bridge is arranged on the outer surface of the nozzle of high temperature pressure vessel and the outer surface of the pipeline connected with nozzle;Heat insulation layer is coated on the outer surface of heat bridge.The application can automatically adjust the outer surface temperature of high temperature pressure vessel nozzle according to fluid temperature by taking heat or releasing heat to the pipeline surface close to fluid temperature in steady-state operating condition and transient operating condition, reduce the temperature difference and thermal stress between inner surface and outer surface of nozzle, and does not need power supply, does not need working medium, is resistant to high temperature, has long service life, works stably, has simple structure and is easy to manufacture.

The invention relates to the technical field of concrete temperature stress, in particular to a method for reducing temperature stress in the concrete hardening process, which comprises the following steps: the inner wall of a discharge port is in contact with a blocking rod, and the bottom end of the blocking rod is fixedly provided with an air pressure rod; through cooperation of a gas collection cylinder, a piston plate, a stirring rod, a gas control pipe, a gas blocking rod II, a gas blocking rod I and a gas storage pipe, after the temperature of air in the stirring cylinder is changed, a gas collecting hole continuously sucks gas above cement, and the gas blocking rod I and the gas blocking rod II are adjusted to move according to the temperature of the air, so that the stirring effect is improved; then the air in the air control pipe is adjusted relative to opening of an airflow cooling mechanism or an airflow heating mechanism, finally the adjusted air is discharged to the position above the cement to reduce the concrete hardening effect, the temperature difference of the concrete does not need to be manually monitored, and meanwhile it is not needed to manually use purified water to neutralize the temperature of the concrete to reduce temperature stress; the cost of an enterprise is reduced, and meanwhile, the functionality of the device is also improved.

The utility model discloses a low temperature resistant type metal hose, which relates to the technical field of metal hoses and comprises a first metal hose and a second metal hose, the lower end of the first metal hose is fixedly connected with a first connecting flange, and the upper end of the second metal hose is fixedly connected with a second connecting flange. And a fixing bolt is arranged on the inner side of the upper end of the first connecting flange. By adopting the structure, the upper arc plate is positioned and inserted at the ends of the two adjacent fixing bolts on the first connecting flange, and then the lower arc plate is positioned and inserted at the threaded ends of the two adjacent fixing bolts; and finally, a reinforcing bolt is positioned and inserted from the upper end of the upper arc plate, penetrates through the cutting grooves of the first connecting flange and the second connecting flange and the lower arc plate, and then is locked by combining a loosening nut, so that the structure does not protrude on the basis of the original mounting characteristics, and instability caused by collision is avoided.

The invention provides an automatic temperature control device and method for mass concrete. The automatic temperature control device comprises a wireless temperature measurement unit, a central control unit and a cooling unit, the wireless temperature measuring unit is buried in mass concrete to be measured and is used for acquiring temperature data in the mass concrete to be measured in real time; the cooling unit is arranged in the mass concrete to be measured and is used for conveying a cooling medium into the mass concrete to be measured so as to adjust the temperature of the medium; the central control unit is connected with the wireless temperature measuring unit and the cooling unit and used for receiving the real-time temperature data sent by the wireless temperature measuring unit and analyzing and processing the temperature data so as to control the cooling unit to adjust the flow or the temperature of the cooling medium when the current temperature data exceeds a preset temperature range. The temperature in the mass concrete to be measured is controlled to be within a preset temperature range. According to the system, the flow and the water temperature of the cooling water pipe can be dynamically adjusted, accurate temperature control is achieved, and the temperature stress and the crack risk are reduced.

This invention belongs to the field of fixed-point punching technology for couplings, and in particular, it is a surface fixed-point punching device for high-precision coupling processing. A hydraulic rod is fixedly connected to the top of the base. An upper plate is fixedly connected to the upper movable end of the hydraulic rod. A connecting plate is provided on the lower side of the upper plate. A third motor is fixedly connected to the inner side of the connecting plate. A drill bit is fixedly connected to the end of the spindle of the third motor. A rotating rod is rotatably mounted on the outer side of the drill bit. A ball bearing for reducing frictional resistance is rotatably mounted at the bottom end of the rotating rod. A paddle is fixedly connected to the lower side of the rotating rod. A cylindrical enclosure is provided on the outer side of the rotating rod. A cavity for placing cooling water is opened on the inner side of the enclosure. An arc-shaped inner groove exists on the upper side of the cavity. One end of the inner groove extends towards the lower side of the rotating rod. An outlet channel is opened on the inner side of the upper and lower middle positions of the enclosure. A baffle is slidably connected to the inner side of the outlet channel.

The invention discloses a geothermal energy hot water supply system, and relates to the technical field of tunnel geothermal energy utilization, the geothermal energy hot water supply system comprises a tunnel phase change energy storage concrete lining and a plurality of shower room bodies, the inner wall of the tunnel phase change energy storage concrete lining is provided with a plurality of accommodating bent grooves, and the inner side of each accommodating bent groove is provided with a first heat exchange pipe; the first heat exchange pipe is connected with a second heat exchange pipe, the end, away from the first heat exchange pipe, of the second heat exchange pipe is connected with a cold water source, the first heat exchange pipe is communicated with the water inlet end of a water storage tank through a heat conduction pipeline, and the water outlet end of the water storage tank is communicated with the shower room body. The water outlet end of the water storage tank is further connected with a drinking water pipe. High-temperature terrestrial heat of the high-temperature section in the tunnel can be transferred to the water storage tank through the second heat exchange pipe and the first heat exchange pipe, so that hot water for bathing or drinking is provided for alpine regions in time, and meanwhile, the terrestrial heat is reasonably utilized.

The invention provides a brazing method of a heat exchanger assembly, the heat exchanger assembly comprises a heat exchanger body and a heat exchange tube, and the outer surface of the heat exchanger body is provided with a heat exchange groove. The brazing method comprises the steps that S1, the heat exchange pipe is coiled into the shape matched with the heat exchange groove in advance through a profiling mold; s2, the surfaces of the heat exchange tube and the heat exchanger body are plated with nickel; s3, the heat exchange tubes are embedded into the heat exchange grooves, and the heat exchange tubes are pressed and fixed through pressing blocks with chamfers; s4, the brazing filler metal is applied to the edge of the contact face of the heat exchange pipe and the heat exchange groove in a differentiated mode, and the surface, where the brazing filler metal possibly flows through, of the heat exchanger body is coated with a solder resist; and S5, the heat exchanger assembly is brazed in a stepped heating mode. According to the method, through cooperative implementation of multiple steps such as heat exchange tube preforming, composite nickel plating, precise fixing, differential brazing filler metal applying and stepped temperature rising, tight attachment of the thin-walled tube and the complex curved surface heat exchanger is achieved, the bonding strength and stability of a brazed joint are improved, brazing defects are effectively eliminated, and the product percent of pass is increased.

The invention discloses a multipurpose converter transformer valve hall firewall structure, which comprises a flat plate wall body, a deformation joint and a fire fighting equipment platform, and is characterized in that the flat plate wall body comprises a transverse wall body for replacing a valve hall outer wall and a longitudinal wall body for separating a plurality of converter transformers; the deformation joint is arranged at the junction of the transverse wall body and the longitudinal wall body and is arranged to be in a T shape. The deformation joint is filled with a refractory material; the fire-fighting equipment platform is arranged at the top end of the counter-fire side of the transverse wall body; the fire-fighting equipment platform is provided with a fire-fighting nozzle, and a pipeline is arranged in the fire-fighting equipment platform. Compared with the prior art, the T-shaped deformation joint is arranged on the back-to-fire surface of the joint of the longitudinal wall body and the transverse wall body of the firewall, and the deformation joint is filled with the refractory material, so that on one hand, the wall body has certain expansion and contraction capacity to weaken temperature stress; on the other hand, the wall surface is divided, and the problems that the wall surface cracks and the durability of the wall is affected due to the fact that the cast-in-place firewall is too long, and internal stress of the wall is generated when concrete is solidified, heated and cooled are solved.

The invention relates to a preparation method of a functional concrete admixture with high impermeability and crack resistance. According to the technical scheme, a proper amount of deionized water and a prepared GO-PCs solution are sequentially added into a reaction container, stirring is started, then a certain amount of organic silicon modified acrylic emulsion, vinyl acetate-acrylic emulsion, polyvinyl alcohol, sodium gluconate, glycerol, xanthan gum and a defoaming agent are sequentially added, and the time interval of adding each raw material is 2 minutes; after all the materials are added, continuously stirring for 30 minutes, and then adding the air entraining agent; and continuously stirring for 5 minutes to finish the preparation of the product. The anti-permeability concrete has the beneficial effects that the anti-permeability performance of the concrete is greatly improved from traditional P6-P12 to P20 or above, and the limit anti-permeability performance can exceed P40; product application is simple, material putting is simpler and more convenient, and production and construction are more facilitated; compared with a traditional product, the construction performance, the mechanical performance and the durability of the concrete are all improved to different degrees, and the anti-cracking capacity is obviously improved.

The present invention belongs to the technical field of casting, and discloses a cooling and heat dissipation device for improving the solidification efficiency of castings, including a water inlet pipe, a water outlet pipe and a PLC controller, wherein a plurality of cooling modules arranged in parallel are arranged between the water inlet pipe and the water outlet pipe; the cooling module includes a sealed cooling box, wherein one end of the sealed cooling box is provided with a water inlet connected to the water inlet pipe, and the other end is provided with a water outlet connected to the water outlet pipe, a temperature control valve is arranged on the water inlet, and a temperature sensor is arranged on the water outlet; a cooling pipe is arranged in the sealed cooling box, wherein one end of the cooling pipe is connected to the water inlet, and the other end is connected to the water outlet; the PLC controller is connected to the temperature control valve and the temperature sensor. The device has strong controllability and high controllable precision, and can make various parts of the casting cool and solidify according to the required temperature gradient. The present invention also discloses a method for controlling the solidification of castings using the device, wherein the method has strong controllability and high controllable precision, and the obtained castings have high quality.

The application provides a peanut drying machine and drying method based on microwave and hot air cooperation, wherein the drying machine comprises a drying main cabin, a multifunctional treatment cabin is connected to one side of the drying main cabin, and a driving device drives a material bucket to revolve around a hot air duct and revolve around a central axis of the material bucket. The material bucket is exchanged between the drying main cabin and the multifunctional treatment cabin through a transfer track, a plurality of microwave devices are arranged in the circumference of the shell of the drying main cabin, the microwave devices are used for emitting microwaves to dry the peanuts in the material bucket, and the outer part of the multifunctional treatment cabin is respectively connected with a feeding device and a discharging device. The application seamlessly integrates three key processes of preheating, drying and tempering in one equipment, realizes automatic switching through physical rotation, forms a complete closed-loop processing chain, greatly simplifies the production line and reduces the material turnover loss. Through the uniform temperature in the preheating stage and the slow recovery in the tempering stage, the color, flavor and nutritional ingredients of the peanuts can be better maintained.

This invention discloses a method for forming ultra-thin stainless steel pipe fittings, relating to the field of stainless steel pipe production and processing technology. It aims to solve the problems of branch pipe rupture and inner wrinkling during the current hydroforming process of ultra-thin stainless steel pipe fittings. The method includes: S1: billet preparation and pretreatment; S2: mold and sealing assembly; S3: staged collaborative forming; S301: pre-expansion and mold-fitting stage, where the internal pressure is increased to 0.8 MPa at a rate of 0.1 MPa / s and maintained stably; S302: main forming precise material replenishment stage, employing a gradient pressure increase strategy; S303: forming stress release stage, maintaining a stable internal pressure of 6-7 MPa for 10 seconds to ensure the billet completely fits the mold cavity, followed by a staged pressure relief method. This invention, through the application of a nano-lubricating film coating on the inner wall of the billet, low-temperature preheating treatment, stress-dispersing mold design, and the collaborative control of gradient pressure increase and real-time monitoring and material replenishment during the main forming stage, achieves effective dispersion of tensile stress concentration at the top of the branch pipe of the ultra-thin stainless steel pipe fitting and precise material replenishment, significantly reducing the risk of rupture.