178results about How to "Improve roundness" patented technology

The invention belongs to the technical field of optical cable preparation and intelligent manufacturing, and particularly relates to a loose tube containing light-weight chemical fiber paste, an optical cable and a light-weight chemical fiber paste coating method. According to the loose tube containing the light chemical fiber paste, the optical fiber and the multiple layers of fiber paste on the surface of the optical fiber are arranged in the loose tube, and the coated multiple layers of fiber paste are divided into the inner-layer fiber paste, the middle-layer fiber paste and the outer-layer fiber paste in the direction away from a fiber core of the optical fiber; wherein the content of bubbles in the inner-layer fiber paste and the content of bubbles in the outer-layer fiber paste are both lower than the content of bubbles in the middle-layer fiber paste, and the viscosity of the inner-layer fiber paste and the viscosity of the outer-layer fiber paste are both higher than the viscosity of the middle-layer fiber paste. The loose tube containing the light chemical fiber paste provided by the invention is qualified in various performances, can integrally reduce the use amount of the fiber paste by 10-15%, can reduce the consumption of petrochemical products, can reduce the weight of an optical cable and the matching cost, saves resources, and is environment-friendly.

The invention belongs to the field of biological medicine, and particularly relates to a polycaprolactone microsphere with narrow particle size distribution and a preparation method thereof. The preparation method comprises the following steps: S1, dissolving polycaprolactone in an organic solvent to obtain an oil phase solution; s2, adding an emulsifier into water, and stirring until the emulsifier is completely dissolved to obtain a water-phase solution; s3, adding the water-phase solution into the oil-phase solution while stirring to obtain a primary emulsion; s4, enabling the primary emulsion to pass through membrane holes of a membrane tube under a pressurization condition, forming polycaprolactone liquid drops in the aqueous phase solution, and taking away the polycaprolactone liquid drops by the circularly flowing aqueous phase solution to obtain a suspension emulsion; s5, stirring the suspension emulsion, removing the organic solvent, and curing the microspheres to obtain a polycaprolactone microsphere suspension; s6, the polycaprolactone microsphere suspension is washed with water and sieved, and wet pellets are obtained; s7, the wet pellets are collected, dried and screened, the polycaprolactone microspheres are obtained, the yield is high, the particle size is uniform, and the particle size span is smaller than or equal to 0.8.

The invention discloses a GH738 alloy bar large-deformation semi-continuous efficient rolling device and technology. The requirements for the grain size and the durability are met at the same time by optimizing the heating and deformation technology in the semi-continuous rolling process. A large-deformation semi-continuous efficient rolling device and a corresponding process are adopted, wherein the large-deformation rolling is 50%-80%; heat is supplemented in the rolling process, and the blank temperature is increased; the finish rolling temperature is increased; and the rolled blank is rapidly heated by an induction coil, and hot straightening is carried out. The method disclosed by the invention has the beneficial effects that (1) the mode of large deformation and heat compensation by using a heating furnace midway is adopted, and the standard grain size requirement of grade 3-grade 6 is met; (2) the rolled blank is heated through an induction coil to be rapidly heated, hot straightening is carried out, and the roundness and the size of the bar are improved; and after standard heat treatment, a surface stress layer cannot be generated due to straightening, so that a coarse-grain ring cannot be generated.

The invention relates to the technical field of leaky coaxial cable production, in particular to a leaky coaxial cable production method which comprises the following steps: S1, welding an inner conductor; s2, foaming and extruding to form an insulating layer; s3, seamless welding of the outer conductor; s4, performing laser hole cutting on the outer conductor through laser processing equipment; and S5, sheath processing. According to the leaky coaxial cable production method, after the outer conductor is seamlessly welded into the circular tube, slotted hole cutting is carried out on the outer conductor through laser, the roundness of the outer conductor can be better, meanwhile, the situations of slotted hole deformation, wrinkling and the like can be reduced, and the cable performance is improved.

The invention relates to the technical field of copper wire annealing devices, in particular to a cable copper wire annealing device which comprises a rack and two copper wire bodies, a motor is installed on the rack, a chain belt is installed at the output shaft end of the motor in a transmission mode, and an electric heating frame, a reciprocating guide module and a water cooling mechanism for conducting water cooling on the copper wire bodies are installed on the rack. The reciprocating guide module is in transmission connection with a reciprocating twisting frame capable of moving left and right in a reciprocating mode, the positions, corresponding to the two copper wire bodies, of the reciprocating twisting frame and the electric heating frame are each rotationally connected with two symmetrically-arranged electrode wheels, and a copper wire tensioning mechanism and a shaking generation component which are matched with the reciprocating guide module are installed on the rack. The cable copper wire annealing device has the beneficial effects that when the cable copper wire annealing device works, annealing, water cooling, oxide removing, water cooling and rounding shaping operations of cable copper wires can be integrally achieved, and through the integrated functions, the functionality of the cable copper wire annealing device is effectively improved.

The utility model belongs to the technical field of cutting tools, and particularly relates to a cutting tool which comprises a lathe tool rest, two mounting grooves are formed in the front end and the rear end of the lathe tool rest respectively, adjusting assemblies are mounted on the outer walls of the front end and the rear end of the lathe tool rest respectively, a cutting tool is inserted into the mounting groove in the front end, and a rack is fixedly arranged on the front wall of the cutting tool. A plurality of mounting holes are formed in the top surface of the lathe tool rest in a front-back symmetrical structure, hexagon socket screws are in threaded connection with the interiors of the mounting holes, a water tank is fixedly arranged in the middle of the top surface of the lathe tool rest, the top surface of the water tank communicates with a filling pipe, a cooling mechanism is arranged on the right wall of the water tank, the adjusting assembly comprises a C-shaped block, and the inner wall of the C-shaped block is fixedly connected with the outer wall of the lathe tool rest. Uniform heat dissipation of the cutting tool is achieved, deformation caused by uneven heating of the cutting tool is effectively reduced, the roundness and cylindricity of a machined part by the cutting tool are improved, the surface roughness is reduced, the disordered corrugation phenomenon is reduced, and the machining effect of the machined part is improved.

The invention provides a high-compaction phosphate positive electrode material, a preparation method thereof and a lithium ion battery positive electrode, the phosphate positive electrode material comprises a phosphate core and a B-C composite coating layer coating the surface of the phosphate core, and the B-C composite coating layer comprises BC3, borate and amorphous carbon; the general formula of the borate is MxByOz, M comprises Li and / or Fe, x is 1-3, y is 1-4, and z is 3-7; the preparation method comprises the following steps: mixing a phosphate precursor material, a boron source and a carbon source, and sequentially carrying out ball milling and sintering to obtain the high-compaction phosphate positive electrode material. According to the invention, the boron source can be melted at a high temperature and is used as a fluxing agent to reduce the surface tension of particles, improve the morphology of the particles and improve the compaction density of the phosphate positive electrode material.

The invention relates to a composite spheroidizing agent, a composite spheroidizing inoculation method and nodular cast iron for a wind power casting, and belongs to the technical field of metal casting machining. The composite spheroidizing agent comprises a light rare earth spheroidizing agent and a heavy rare earth spheroidizing agent, and the light rare earth spheroidizing agent is prepared from, by weight, 0.8%-1.2% of RE, 6.0%-7.0% of Mg, 1.5%-2.5% of Ca, 1.0%-3.0% of Ba, 42%-46% of Si and the balance Fe; the heavy rare earth spheroidizing agent comprises the following chemical components in percentage by weight: 0.5 to 1.5 percent of RE, 5.5 to 6.5 percent of Mg, 1.5 to 2.5 percent of Ca, 1.0 to 3.0 percent of Ba, 44 to 48 percent of Si and the balance of Fe. According to the invention, light and heavy rare earth composite spheroidizing and a triple inoculation method of ladle bottom, tapping stream and pouring instantaneous are adopted, so that the spheroidizing rate is increased, the graphite form and distribution are improved, and the ductility can be increased under the condition of ensuring high strength.

The invention relates to the technical field of dry granulation, in particular to dry granulation machine equipment and a process thereof.The dry granulation machine equipment comprises a hopper and two granulation rollers inserted in the hopper in parallel, the rotation directions of the two granulation rollers are opposite so as to drive materials to move from top to bottom, and the two granulation rollers are arranged in the hopper. A plurality of arc-shaped convex strips are arranged on the peripheral wall of each granulation roller, the convex strips jointly form an annular wavy structure, the convex strips extend in the axial direction of the granulation rollers, the two sides of each convex strip are each provided with two extrusion groove sets, and each extrusion groove set comprises a plurality of extrusion grooves which are formed at equal intervals and extend in the extending direction of the corresponding convex strip. In the using process, firstly, materials are put between the two granulation rollers through the top of the hopper, then the two granulation rollers are driven to rotate in the opposite directions, and along with rotation of the granulation rollers, the extrusion grooves in the two granulation rollers are close to each other and then away from each other, so that the materials are extruded.

The invention discloses a water jet assisted millisecond laser-femtosecond laser secondary composite hole making method. The method comprises the steps that S1, an iron-based high-temperature alloy material is pretreated; s2, preliminarily processing the iron-based high-temperature alloy material through millisecond laser assisted by water jet, and punching for the first time; s3, the transferred iron-based high-temperature alloy material is subjected to finish machining under femtosecond laser, and second-time punching is conducted in combination with ultrasonic vibration; and S4, after punching is completed, the iron-based high-temperature alloy material is cooled, and the quality and precision of machined holes are checked. According to the method, water jet is used for assisting millisecond laser to conduct preliminary punching, heat affected zones are reduced, a good hole shape foundation is laid, fine machining is conducted in combination with ultrasonic vibration assisted femtosecond laser, the roundness and surface quality of holes are further improved, and the machining precision is improved. The problems of poor hole roundness and low machining precision caused by high thermal conductivity of the iron-based high-temperature alloy in femtosecond laser drilling are effectively solved, and the machining quality and precision are remarkably improved.

The invention relates to the technical field of valve bag packaging, in particular to a valve bag packaging device which comprises a discharging machine, a mounting frame, a plurality of first suction cups and two bag clamping arms, the mounting frame is composed of a connecting frame and a limiting plate connected to the bottom face of the connecting frame, the limiting plate is in an arc shape, and the top of the limiting plate protrudes upwards; a through groove in the connecting frame extends downwards and penetrates through the top of the limiting plate, a moving plate is vertically and slidably inserted into the inner wall of the through groove, the first suction cups are connected to the bottom face of the moving plate, and a plurality of adsorption holes are formed in the inner wall of the limiting plate. The two sides of the bottom end of the limiting plate are connected with multiple first air pipes, and the two sides of the bottom end of the end, close to the discharging pipe, of the limiting plate are connected with second air pipes. The opening degree of a bag opening of the valve bag can be increased, the roundness of the bag opening can be improved, the valve bag can be conveniently and efficiently arranged on a discharging pipe of a discharging machine in a sleeving mode, and continuous machining is facilitated through the device.

The present invention discloses a micro-pill preparation device and preparation method based on automatic roundness adjustment compensation, belonging to the technical field of micro-pill preparation, comprising a preparation body, a feeding cavity is arranged on the top, a discharging cavity is arranged on the bottom, a vibration device is arranged inside, a material dividing device is arranged inside the feeding cavity, comprising a rotating column rotatably connected with the preparation body, the vibration device comprises a vibration plate, the material dividing device divides the blank pill cores transported into the feeding cavity, the blank pill cores are subjected to micro-pill preparation treatment in the preparation body, so that the drug powder is attached to the outer wall of the blank pill core, after being treated by the preparation body, the blank pill cores form micro-pills, and then the micro-pills move to the side close to the vibration device, the vibration device shakes off the drug powder that is not bonded to the surface of the micro-pills, and then the unbonded drug powder is separated from the surface of the micro-pills and transported to the preparation body again for adhesion treatment. The present invention is applied to the micro-pill production of pharmaceutical capsule preparations, which can improve the micro-pill preparation quality and drug powder utilization rate.

The invention discloses modified high-carbon alloy steel and a preparation method and application thereof, and belongs to the technical field of high-carbon alloy steel for aluminum alloy forming dies. The preparation method disclosed by the invention comprises the following steps: carrying out electroslag remelting on a high-carbon alloy steel rod to obtain a casting blank; carrying out thermoplastic deformation on the casting blank to obtain a blank; the blank is annealed, so that carbides in the blank are eliminated or become fine particles, spherical graphite can be separated out, and the modified high-carbon alloy steel is obtained; the particle size of the fine particles is smaller than 10 microns. According to the method, coarse and large carbides which are difficult to eliminate in the high-carbon aluminum alloy forming die steel containing strong carbide forming elements such as Cr, Mo and V or medium-strong carbide forming elements are subjected to rapid and basic graphitization through a thermoplastic deformation and high-temperature graphitization combined process; the technical problem that carbide decomposition and graphite precipitation control are difficult to realize in the existing method is solved.

The invention discloses a silicon-based ceramic core capable of regulating and controlling strength based on angle-ball ratio and a preparation method thereof, the silicon-based ceramic core comprises the following substances in percentage by mass: 75-90wt% of ceramic powder and 10-25wt% of plasticizer, and the ceramic powder comprises the following substances in percentage by mass: 67-85wt% of quartz glass powder, 13-32wt% of mineralizer and 0.1-2wt% of pore-forming material. The method comprises the following steps: pretreating quartz glass powder with various particle sizes and spherical powder in aluminum oxide with various particle sizes; pretreating the quartz glass powder of each grade of particle size and the aluminum oxide of each grade of particle size according to a designed angle-ball ratio; uniformly mixing ceramic powder and a plasticizer to obtain silicon-based ceramic core slurry; and carrying out injection molding to obtain a silicon-based ceramic core green body, and roasting to obtain the silicon-based ceramic core with the strength regulated and controlled based on the angle-ball ratio. A series of silicon-based ceramic core systems with approximately linear adjustable strength can be obtained, and different requirements of different working conditions, different inner cavity structures, different alloy types and the like of blade investment casting on the strength of the ceramic core can be met.

The utility model discloses a disposable nasogastric tube, relates to the technical field of medical instruments, and aims to provide a disposable nasogastric tube which not only can ensure rapid and accurate intubation, but also can relieve the pain of a patient to the greatest extent, and comprises a hose and a connecting end, one end of the hose is provided with an arc covered edge, and the other end of the hose is sleeved outside the connecting end. Comprising a connecting pipe used for being connected with a hose, a main port used for feeding or drainage and a flushing port used for air flushing or water flushing, and the main port and the flushing port are both communicated with the hose through the connecting pipe. Damage to the nasal cavity or the gastrointestinal tract inner wall of a patient in the insertion process is avoided as far as possible, and discomfort and pain of the patient are relieved.

The utility model discloses a photoelectric composite cable which comprises an inner core and is characterized in that the inner core is composed of two optical units, two electric units and four ground wires, the two optical units and the two electric units are distributed in a cross shape in the inner core, and the four ground wires abut against the positions between the optical units and the electric units in an X shape; a reinforcing piece, a wrapping tape, a shielding layer and a sheath are sequentially distributed outside the inner core from inside to outside; according to the utility model, the stainless steel soft steel in the optical unit is used for the first protection, the aramid fiber layer is used for the second protection, and the reinforcing member is used for the third protection, so that the compression resistance and the clamping resistance of the optical fiber are fully enhanced through the three protection layers; and meanwhile, the aramid fiber layer and the reinforcer are woven by adopting a plurality of strands of aramid fibers, so that the protection effect of a traditional metal armor can be achieved, and the weight of the cable is reduced on the basis of ensuring the tensile and compressive properties of the cable.

A gas-guide tube renovation method comprises the following steps that S1, a gas-guide tube is cut into a plurality of sections of tube bodies, then the inner wall renovation procedure and the outer wall renovation procedure are conducted on the tube bodies, and the inner wall renovation procedure S11 comprises the steps that an inner hole of each tube body is renovated through a reaming tool, and meanwhile cooling liquid is continuously injected from the tail end of the inner hole of each tube body; in the outer wall renovating procedure S12, the pipe body is driven to rotate around the axis of the pipe body and is moved in the axial direction, so that the peripheral wall of the pipe body from the head end to the tail end is ground and renovated by a grinding wheel; s2, the pipe body subjected to the inner wall renovating procedure and the outer wall renovating procedure is degreased and cleaned through a cleaning solution; and S3, the cleaned pipe body is re-spliced or welded to be recovered into the gas-guide pipe. According to the renovating method of the scheme, a large amount of processing time can be saved, the processing cost is reduced, new materials do not need to be input again, the material cost is saved, and therefore the use cost of a client side is effectively reduced. The invention further provides gas-guide tube renovation equipment.

The invention provides a sintering method of a large-size silicon carbide ceramic ball, which belongs to the technical field of silicon carbide ceramic ball preparation, and specifically comprises the following steps: forming a green body ball, turning the green body ball, processing a sintering bottom support tool, loading the ball into a mold, sintering and post-processing. A special auxiliary tool is combined, the tool adopts a material formula and a pressing process which are the same as those of a green body ball, the green body ball and the auxiliary tool have the same shrinkage rate during sintering, the problems of deformation and poor roundness caused by high-temperature shrinkage in the sintering process of the green body ball can be effectively reduced, the roundness and uniformity of the prepared silicon carbide ceramic ball are remarkably improved, and the service life of the silicon carbide ceramic ball is prolonged. And the method is suitable for preparing industrial high-performance ceramic balls.

The invention belongs to the technical field of leading-out crystallizers, and particularly relates to a continuous casting down-leading crystallization device for preparing high-quality alloy materials, which comprises a fixed cover plate and a first leading-out pipe, the first leading-out pipe is arranged on the bottom end face of the fixed cover plate, and an electromagnetic stirrer is arranged on the upper end face of the fixed cover plate. An inner wall pipe is arranged between the electromagnetic stirrer and the first outlet pipe, a copper sleeve is arranged outside the inner wall pipe and in the first outlet pipe, a first flowing cavity is formed outside the copper sleeve and in the first outlet pipe, a first water cooling assembly is arranged outside the first flowing cavity, and a second outlet pipe is arranged below the first outlet pipe. A second water cooling assembly is arranged in the second outlet pipe; by adopting a novel lower extraction method, large-scale production treatment of the casting blank can be completed, through arrangement of structures such as the electromagnetic stirrer, the inner wall pipe and the first water cooling assembly, the problems that internal elements of the casting blank are not uniformly distributed, the surface is prone to oxidation cracking and the like can be solved, and the forming quality of the casting blank is effectively improved.

The invention provides a multi-pole magnetic circuit manufacturing method, a multi-pole magnetic circuit and a stepping motor. The manufacturing method comprises the following steps: S1, providing a plurality of pieces of first magnetic steel, wherein the cross section of the first magnetic steel is in a sector ring shape; s2, splicing and assembling the plurality of pieces of first magnetic steel to obtain a first cylinder; and S3, grinding the side surface of the obtained first cylinder by adopting a grinding process to obtain a second cylinder, and then electroplating the outer surface of the obtained second cylinder to form a coating, thereby obtaining the multi-pole magnetic circuit for the stepping motor. According to the manufacturing method of the multi-pole magnetic circuit, the multiple pieces of first magnetic steel with the large size are prepared at first, then the obtained first magnetic steel is spliced and assembled to obtain the first cylinder with the large outer diameter size, the side face of the obtained first cylinder is ground through the grinding technology to obtain the second cylinder with the small outer diameter size, and therefore the multi-pole magnetic circuit is manufactured. The splicing operation difficulty is reduced, and the roundness and concentricity of the multi-pole magnetic circuit and the reliability of the magnetic circuit are improved.

A resistance tape winding mechanism and method, belonging to the field of electronic component packaging devices. Including variable diameter shaft core, limit plate positioning block, foot switch, PLC controller, servo controller, tension spring, rack shell, feeding limiting mechanism, sensor mounting bracket, sensor, linear bearing seat, equipment platform, guide shaft, limit plate, pressing block, servo motor, torsional spring, servo motor mounting seat. The variable diameter shaft core is used as the winding shaft core, and different gears are selected for winding resistance carrier tapes of different lengths. Manual feeding is adopted, the device is started to automatically wind the tape, the device automatically stops after winding, then the wound tape is manually removed, and the outermost circle is manually fixed with adhesive tape. The purpose of achieving the same outer diameter of resistance carrier tapes of different lengths after winding into products is achieved, and the consistency of the outer diameter of the wound tape, the roundness of the wound tape, the efficiency of the wound tape and the consistency of the quality are improved. It is used for winding tape-shaped packaging products.

The invention discloses a checking plate of a phased array ultrasonic welding spot detector and a checking method of the checking plate. The checking plate comprises a substrate, and a detection column perpendicular to the substrate is arranged on the front face of the substrate; a first groove matched with a detector probe is formed in the back surface of the substrate; the axis of the detection column is collinear with the center line of the first groove. And the base plate and the detection column are made of Q235A steel. The checking plate has the advantages that the checking plate is made of Q235A steel similar to automobile steel, the cylindrical detection column is arranged on the front face, the first groove matched with a detector probe is formed in the back face, the axis of the detection column and the center line of the first groove are collinear, a detector can recognize the detection column and conduct accurate measurement, and the detection accuracy is improved. The accuracy of the phased array ultrasonic welding spot detector can be accurately evaluated, the credibility of the measurement result of the phased array ultrasonic welding spot detector is ensured, and the problem that the phased array ultrasonic welding spot detector cannot be measured in China is solved.

The application discloses a railway locomotive cable outer sheath extrusion assembly and belongs to the technical field of cable manufacturing. The railway locomotive cable outer sheath extrusion assembly comprises a first extruder, a cooling mechanism and a second extruder through which a cable passes in sequence, the first extruder is used for extruding a first sheath layer to the cable, the second extruder is used for extruding a second sheath layer to the outside of the first sheath layer, the cooling mechanism comprises a water collecting tank, a spraying chamber, a blowing chamber and a drying chamber arranged at the tank opening of the water collecting tank, the spraying chamber is used for spraying cooling water to the first sheath layer, the blowing chamber is used for blowing off water drops on the surface of the first sheath layer, the spraying chamber and the blowing chamber are arranged alternately, and the drying chamber is provided with a third cylindrical passage, second blowing heads are spirally arranged in the inner circumferences of the third cylindrical passage, and the second blowing heads are used for drying the first sheath layer. The application further provides a railway locomotive cable outer sheath extrusion method. The PE sheath layer and the low-smoke halogen-free flame-retardant oil-resistant layer are extruded in one time by using the extrusion assembly in a continuous co-extrusion mode, so that the cable has good roundness.

The present invention discloses a straightening device for a stainless steel pipeline, comprising a base, on which at least two outer straightening mechanisms are arranged along the axial direction of the stainless steel pipe; each outer straightening mechanism comprises a plurality of outer pressure rollers arranged around an axis, and the base is also connected with at least two inner straightening mechanisms via a connecting shaft; the arrangement direction of each inner straightening mechanism is the same as that of the outer straightening mechanism, the inner straightening mechanism corresponds to the outer straightening mechanism one by one, and the inner straightening mechanism is located inside the outer straightening mechanism. The straightening device for a stainless steel pipeline provided by the present invention can act on the inner and outer sides of the stainless steel pipe at the same time, and the straightness and roundness of the stainless steel pipe after straightening are both high, thereby improving product quality.

The invention discloses a construction method of a colorectal tumor model based on 3D printing, which comprises the following steps: dissolving methacrylated gelatin and phenyl (2, 4, 6-trimethylbenzoyl) lithium phosphate together to obtain a mixed solution, adding colorectal cancer cells HCT-116 and human skin fibroblasts BJ into the mixed solution, and uniformly mixing to obtain bio-ink; and loading the bio-ink into a charging barrel of an extrusion type biological 3D printer for 3D printing to obtain the tumor cell-carrying gel microspheres, and culturing in vitro to obtain the tumor cell-carrying gel microspheres. According to the method, the upper limit of cell density of liquid drop biological 3D printing is broken through, stable printing of biological ink with the cell density as high as 1 * 10 < 8 > cells / mL is successfully achieved through optimization of a rheological window, the density is close to the physiological level of solid tumors, the printed tumor model can truly simulate the high compactness of the tumors and the nutrition / oxygen gradient effect caused by the high compactness of the tumors, and the tumor model has good application prospects. And an experimental platform closer to the in vivo is provided for researching the microenvironment heterogeneity in the tumor.

The utility model provides a novel etching stainless steel screen printing silk screen which comprises a mesh layer and a crack layer, the crack layer is arranged below the mesh layer, the mesh layer comprises a first rectangular mesh layer and a second rectangular mesh layer, the crack layer comprises a first crack layer and a second crack layer, and the first crack layer and the second crack layer are arranged on the first rectangular mesh layer and the second rectangular mesh layer respectively. The lower portions of the first rectangular meshes can be connected with the first crack layer and the second crack layer respectively, and the lower portion of the second rectangular mesh layer can be connected with the first crack layer and the second crack layer respectively. According to the novel etching stainless steel screen printing silk screen, the first rectangular mesh layer and the second rectangular mesh layer are used in cooperation with the first crack layer and the second crack layer, lines and lines can be adopted to form a pattern, the net line interference of each dot can be reduced by 50%, the ink penetrating amount is increased by about 50%, and therefore when the pattern is printed, the number of the lines is reduced, and the printing quality is improved. And the roundness and fineness of the lines can be improved by about 50%.

The application relates to the technical field of grinding equipment, and particularly discloses an electric tool output shaft mandrel positioning grinding equipment. The electric tool output shaft mandrel positioning grinding equipment comprises a spindle box and a grinding device, the spindle box is provided with a spindle, the spindle is provided with a self-centering clamping mechanism, the grinding device comprises a rack, a first driving device and a second driving device, the rack is provided with a rotating disc through a hollow shaft base, a plurality of sliding grooves are arranged on the rack, sliding seats are arranged in the sliding grooves, hollow guide pins and axles are arranged on the sliding seats, and a grinding wheel and a driven wheel are arranged on the axles; a guide groove matched with the hollow guide pins is arranged on the rotating disc, the rotating disc is driven by the second driving device, and all the driven wheels are driven by the first driving device. When fine grinding is carried out, the grinding wheel simultaneously works around the output shaft mandrel, the circumferential grinding cutting forces on the output shaft mandrel are offset, and the problems of position deviation, bending deformation and machining vibration caused by unilateral force on the output shaft mandrel are avoided, and the fine grinding precision is obviously improved.

The invention discloses a pipeline roundness correction device, a negative pressure shaping box and a pipeline extrusion assembly.The pipeline roundness correction device comprises a rotary driving part, a plurality of roundness correction parts and two groups of roundness measurement parts, the rotary driving part is vertically arranged in the left-right direction, and the roundness correction parts are annularly and evenly installed at the driving end of the rotary driving part at intervals; the two groups of roundness measuring pieces are arranged at the front end and the rear end of the rotary driving piece, the roundness measuring piece located in the front is a first roundness measuring piece, the roundness measuring piece located in the rear is a second roundness measuring piece, and an inner hole of the rotary driving piece is used for a pipeline to penetrate in the front-back direction. The first roundness measuring piece is used for monitoring whether the size error of the pipeline is qualified or not, the roundness correcting piece is used for conducting roundness correcting treatment on the pipeline with the unqualified size error under driving of the rotary driving piece, the second roundness measuring piece is used for monitoring whether the size error of the pipeline subjected to roundness correcting is qualified or not, the structure is simple, and the roundness correcting effect is good.

This utility model discloses a video transmission cable for a robot, comprising: a data transmission line consisting of at least two signal transmission cores, a power line consisting of at least two power transmission cores, and a sheath covering the outside of the data transmission line and the power line. Each of the signal transmission cores and the power transmission cores includes a conductor and an insulation layer covering the conductor. A first shielding strip is wrapped around the outside of the cable core formed by twisting at least two signal transmission cores and at least two power transmission cores. A metal braided layer and a wrapping layer are sequentially arranged between the first shielding strip and the sheath layer. The sheath layer slidably covers the outside of the wrapping layer. A second shielding strip is wrapped around the outside of the data core formed by twisting at least two signal transmission cores and a current-carrying core. This utility model can improve the shielding capability and the range of signal shielding, and effectively avoid the wear and interference of the metal braided layer caused by the relative sliding between layers.

The invention relates to the technical field of steel plate processing, and discloses a petroleum pipeline thick-wall steel plate pre-bending and edge rolling all-in-one machine which comprises a machine base, a supporting edge rolling mechanism installed in the machine base and a steel plate sample arranged above the machine base and further comprises two side frames symmetrically arranged on the two sides of the machine base. A synchronous pre-bending mechanism is arranged at the top of the side frame; synchronous and symmetrical pre-bending of the two ends of a steel plate is achieved through the synchronous pre-bending mechanisms arranged on the two sides of the machine base, a lifting autorotation roller and a pitched roof rotating roller which are installed in a trapezoid frame can apply accurate and adjustable bending force to the two ends of the steel plate at the same time, and procedure interruption and reference deviation caused by turning around and secondary clamping in the traditional technology are eliminated; it is ensured that the curvature radius of pre-bending at the two ends is highly consistent with the forming quality, the overall roundness and straightness of the barrel are remarkably improved, and a fundamental guarantee is provided for subsequent efficient edge rolling and high-quality girth welding.