42results about How to "Guaranteed positive pressure" patented technology

The invention discloses a light spot and powder spot automatic collaboration controlled laser metal added material manufacturing device and a method. The device comprises a connecting joint, a laser focusing head and a sleeve respectively fixed at the upper end and the lower end of the connecting joint, a mobile sleeve slidingly coating the sleeve, a powder feeding nozzle fixed at the lower end of the mobile sleeve, and a numerical control worktable for placing workpieces; the laser focusing head is used for forming light spots on workpiece machined surfaces of a focusing mirror; the powder feeding nozzle is used for gathering powder currents to feed in a machining position to form powder spots on the workpiece machined surfaces; the centers of the light spots and the powder spots are overlapped always; the numerical control worktable is used for driving the workpieces to perform the space movement corresponding to the focusing mirror to control the out-of-focus distance; and a driving device is arranged on the mobile sleeve for driving the powder feeding nozzle to move up and down through the mobile sleeve to control the sizes of the powder spots. When the method forms thick and large workpieces with the cladding layer sizes exceeding the adjusting range, the profile scanning and filling scanning combined path formation is adopted.

The invention belongs to the field of robots, and specifically relates to a pipe-threading robot for a pipeline. The pipe-threading robot for the pipeline comprises a main body and three feet connected with the main body, wherein the three feet are of the same structure and arranged uniformly, and every two of the three feet form an included angle of 120 degrees. The main body is composed of a fixing block, a sliding block, a lead screw and a driving device. The interior of the fixing block is fixedly connected with a bare shaft part of the lead screw. The interior of the sliding block is fixedly connected with a thread part of the lead screw. The driving device installed at one end of the fixing block drives the lead screw to rotate. Each foot comprises a parallelogram four-bar mechanism, a guiding and supporting bar, rolling wheels and a driving device. One bar piece of each parallelogram four-bar mechanism is fixedly connected with the fixing block. Bars adjacent to each bar piece are connected with one end of each guiding and supporting bar. The other end of each guiding and supporting bar is connected with the sliding block. The sliding block drives each guiding and supporting bar to rotate in a sliding mode, and then the corresponding parallelogram four-bar mechanism is driven to rotate. Rolling wheels installed on each parallelogram four-bar mechanism are driven by the corresponding independent driving device. A damping device is installed on each guiding and supporting bar.

The invention provides a metal semi-solid state melt extrusion additive manufacturing spraying nozzle. The metal semi-solid state melt extrusion additive manufacturing spraying nozzle comprises a containing cavity and a stirring screw rod, wherein the stirring screw rod is coaxially arranged in the containing cavity in a clearance mode; the containing cavity is in a cylindrical shape with a variable cross section, and the diameter of the upper cylinder is larger than that of the lower cylinder; the upper cylinder and the equal-height part of the stirring screw rod form a material melting storage cavity; a plurality of semi-solid state material forming cavities which are gradually reduced by degrees are formed by the lower cylinder and the equal-height part of the stirring screw rod; a supporting frame which is provided with a feeding bin is fixedly arranged at the upper end of the containing cavity, an extrusion spraying nozzle is arranged at the lower end of the containing cavity, anda multi-section type resistance heating assembly, a multi-section water cooling ring assembly and a temperature control system are arranged on the outer side of the containing cavity correspondingly;the supporting frame is provided with a bearing system used for assembling the stirring screw rod, and a feeding assembly communicating with the feeding bin; a driving end of the stirring screw rod is connected with an output end of a speed reducer and the output end of a driving motor, and a free end of the stirring screw rod is in clearance fit with the extrusion spraying nozzle to be used forsqueezing the semi-solid state metal out. According to the metal semi-solid state melt extrusion additive manufacturing spraying nozzle, melt extrusion and forming of a light metal structural materialof aluminum / magnesium alloy with a relatively low melting point are realized.

The invention provides an independent pressurized air supply system for tunnel transverse galleries and an air supply method. The independent pressurized air supply system comprises a fire detection system, a PLC controller and pressurized air supply units corresponding to various tunnel transverse galleries, wherein the PLC controller is connected with the fire detection system and the pressurized air supply units separately. The independent pressurized air supply system has the advantages that the thought that the adjacent galleries of a highway are security areas for each other is reflected in a ventilation and smoke control device; non-accident tunnel wind pickup is achieved in a fire, so that pressurized air supply is carried out on the tunnel transverse galleries, positive pressure of the tunnel transverse galleries on an accident tunnel is ensured, pressurized air supply of the tunnel transverse galleries is achieved and smoke is prevented from entering the tunnel transverse galleries from the accident tunnel. Meanwhile, an air curtain can be further formed on a security door through an air valve to prevent the smoke from entering the tunnel transverse galleries from the accident tunnel, therefore, a security guarantee is provided for personnel evacuation and rescue. The system is combined with engineering practice of a highway tunnel, so that the pressurized air supply device is simplified, and the independent pressurized air supply system is flexible in arrangement, small in engineering scale and high in engineering implementation.

A hinge type dumper hydraulic oil tank comprises a hydraulic oil tank body. An oil return cavity is formed in the top face in a cavity body of the hydraulic oil tank body. An oil return pipe communicating with the oil return cavity is arranged on the side face of the oil return cavity. The other end of the oil return pipe communicates with an oil return port, wherein the oil return port is fixed to the side face of the hydraulic oil tank body and is close to the position of the bottom face, and the oil return port communicates with an outer hydraulic system. The hinge type dumper hydraulic oil tank further comprises a plurality of oil return filters. Oil inlets of the oil return filters are arranged in a cavity body of the oil return cavity, and after penetrating out of the bottom face of the oil return cavity, oil outlets of the oil return filters extend towards the cavity body of the hydraulic oil tank body; and the part between the radial outer circumferential face of each oil return filter and the oil return cavity is sealed. The novel hinge type dumper hydraulic oil tank is provided, the hydraulic system oil liquid cleanliness can be achieved, oil suction and return oil filter element replacement is simple, and stable running of the hydraulic system is guaranteed.

The invention discloses a method for dynamically and continuously producing ultrahigh-strength gypsum. The method comprises the steps: adding water, a water reducer and a buffering agent into gypsum,carrying out uniform mixing, then, injecting the mixture into an autoclave by using a pump, and carrying out a crystal transformation reaction to obtain high-strength gypsum; continuously injecting the high-strength gypsum into a particle size regulating kettle, then, pumping the high-strength gypsum into a stabilizing kettle, adding a set retarder, and carrying out uniform stirring; then, injecting the high-strength gypsum into a liquid-solid separator by using a pump to carry out dehydration, then, making the dehydrated high-strength gypsum continuously enter a drying and dispersing machineby a sealing device, and obtaining dry powder of the high-strength gypsum by a dust collector; and adding a reinforcing agent into the dry powder of the high-strength gypsum to obtain a finished product of the ultrahigh-strength gypsum. Compared with an existing technical scheme, the method has the characteristics such as low production cost, high production efficiency and good product quality.

The invention discloses a positive-pressure joint for needleless medicated transfusion, belonging to the field of medical apparatus and instruments. The positive-pressure joint comprises a rubber plug inner core, a hollow rubber plug, a connecting tube socket and a shell of which the upper and lower ends are through, wherein the connecting tube socket and the lower end of the shell are in connected in a sleeving mode, and a horizontal flow guiding groove, which divides the bottom face of the internal wall of the connecting tube socket horizontally and equally, and two exhausting through holes, which are correspondingly located at the two sides of the horizontal flow guiding groove, are formed in the bottom face of the internal wall of the connecting tube socket; a transfusion tube is inserted to the middle part of the horizontal flow guiding groove; a rubber plug shell which is coaxial with the shell is arranged in the shell, the top face of the rubber plug shell is lower than the top face of the shell, the hollow rubber plug is coaxially located in the rubber plug shell and is supported by the bottom face of the internal wall of the rubber plug shell, sealing structures are respectively formed between the outer circumferential wall of the hollow rubber plug and the inner circumferential wall of the shell and between the outer circumferential wall of the hollow rubber plug and the inner circumferential wall of the rubber plug shell, and two exhausting pipes are further arranged at the bottom of the rubber plug shell and are connected with the two exhausting through holes correspondingly in an inserting mode; at least one longitudinal flow guiding groove which can be communicated with the horizontal flow guiding groove is formed between the radial direction of the outer circumferential wall of the rubber plug shell and the radial direction of the inner circumferential wall of the shell.

The invention discloses a cage type hyperbola spring structure and a socket. The cage type hyperbola spring structure is applied to a jack terminal, the cage type hyperbola spring structure comprises multiple copper hyperbola column-shaped inclined springs and a machine tooled body, laser spot welding circular winding for the multiple copper hyperbola cylindrical inclined springs is carried out to acquire a sealed cylindrical annular structure, the cylindrical annular spring structure is inserted into the machine tooled body, the cylindrical inclined springs are guaranteed not to loose during plugging and unplugging of male / female terminals through inclined riveting necking at a thin wall pipe end portion, moreover, an assembling method can be further employed, an elastic C ring is mounted into the thin wall pipe end portion to realize compaction. According to the cage type hyperbola spring structure, positive pressure of the male / female terminals in a plugging process is guaranteed, stable contact under the condition of super heavy current can be guaranteed, each copper wire in a compression process generates elastic deformation not plastic deformation, service life of products is guaranteed, the spring declination time is prolonged, moreover, the cage type hyperbola spring structure can realize mutual overlapping in a compression process, the elastic deformation space of the springs can be reduced, and the relatively small volume can be guaranteed.

The invention discloses a 3D printing machine. The 3D printing machine comprises a machine box, a forming platform assembly mounted at the upper part of the machine box, a material disc, an adjustable optimal machine assembly mounted at the lower part of the machine box, and a control platform mounted outside the machine box, wherein the forming platform assembly and the adjustable optimal machine assembly are provided with motors; a force feedback system is arranged on the forming platform assembly; and the motors and the force feedback system are electrically connected with a control system of the control platform, so that the lifting speed of a forming platform can be effectively controlled through the mutual cooperation of the control system and the force feedback system. According to the 3D printing machine, an optical machine at the lower part of the machine box is designed as the adjustable optimal machine assembly, the up-and-down motion of the optical machine is controlled through an adjusting device, the focal length is adjustable, and the 3D printing machine is applicable to printing of various breadths and is applicable to printing of printing products of various precision as well.

The invention relates to a sensor, more particularly to a load sensor. The load sensor comprises a stressed elastic main body, a strain gauge set and a bottom cap. Central through holes are arranged at the stressed elastic main body; and a stressed platform, a force guide post and a stepped pedestal are arranged at the stressed elastic main body from top to bottom, wherein the stressed platform, the force guide post and the stepped pedestal are arranged coaxially. An annular stressed plane is arranged on the stressed platform; and a first annular force guide angle that is extended downwardly along the bottom of the inner wall of the force guide post is arranged at a step surface of the top central through hole. The pedestal is a two-layer stepped pedestal; the upper layer surface of the pedestal is provided with a first annular force guide groove that is extended downwardly along the periphery of the bottom of the outer wall of the force guide post; the lower layer surface of the pedestal is provided with an annular stressed isolation groove that is extended downwardly along the periphery of the bottom of the upper layer outer wall of the pedestal; annular grooves are arranged at the bottom of the pedestal and annular stressed releasing grooves are arranged at bottoms of the annular grooves; annular paster surfaces are arranged at bottoms of the annular grooves; and a lead hole that is communicated with the lower layer periphery of the pedestal is arranged at a side wall of one of the annular grooves. Besides, the strain gauge set is arranged on the strain gauge set; and leads of the strain gauge set is externally connected to a measuring circuit or a strain gauge through the lead hole.

The invention discloses a needless connection piece. The needless connection piece comprises a needless connector and a rubber plug, wherein the needless connector comprises an access port, an output port and a cavity with an inner cavity, an inner core seat is arranged in the inner cavity, the rubber plug comprises a solid portion and a hollow portion, at least one groove is formed in the side wall of the solid portion, at least one rib used to increase elastic recovery ability of the hollow portion is arranged in the hollow portion, the rubber plug is arranged in the inner cavity of the needless connector, the solid portion and the access port of the needless connector form a seal structure, and the hollow portion is installed in the inner core seat in connection mode. According to the needless connection piece, the at least one rib used to increase the elastic recovery ability of the hollow portion is arranged on the inner wall of the hollow portion. The needless connection piece has strong resilience force, guarantees positive pressure, enables the rubber plug to have enough mechanical strength, uses the guiding rib which is in S shape and has strong resilience force, enables the guiding rib to limit the deformation direction of the rubber plug, and prevents the rubber plug from jamming in the inner cavity.

The invention relates to a low-noise two-way servo pump source which comprises an oil tank, a pump source assembly, a valve control set, a hydraulic cylinder, a cooler and an oil return filter. The pump source assembly comprises a double-shaft-extension servo motor, a first hydraulic pump, a second hydraulic pump, a first clutch and a second clutch. The valve control sets comprise the first valve control set and the second valve control set, the hydraulic cylinder comprises a cylinder body and a piston, and the piston is slidably connected to an inner cavity of the cylinder body and divides the inner cavity of the cylinder body into a first cavity and a second cavity. Reciprocating motion of the hydraulic cylinder is achieved through forward rotation and reverse rotation alternate motion of the double-shaft-extension servo motor, the reciprocating motion speed of the hydraulic cylinder is achieved by adjusting the rotating speed of the double-shaft-extension servo motor, and therefore bidirectional speed regulation and direction control of the whole hydraulic transmission system are achieved. The device is simple in structure, low in noise, high in reliability and wide in speed regulation range.

The invention provides an auto-disposal auto-exhaustion anti-reflux needleless infusion set facilitating clinical operation. The needleless infusion set has auto-exhaustion and automatic liquid stopping functions, an infusion hose replaces a steel needle, and the steel needle is prevented from piercing the blood vessel due to walking or other actions, resulting in that medical fluid flows into subcutaneous tissue to cause bulging or other injury. When the infusion set is in use, the steel needle is fixed on a base to avoid injury to medical staff. After use, the infusion set can be disposed automatically to avoid secondary utilization by lawbreakers. The other purpose of the infusion set is to improve a liquid medicine filter, the improved filter can filter out insoluble particles in the liquid medicine to the uttermost extent, and medication safety is assured.

The invention discloses a fresh air purifying method. The method sequentially performs the following steps of initial-effect filtration treatment, medium-effect filtration treatment, anti-freezing preheating treatment, first-level surface cooling dehumidification treatment, water spraying treatment, second-level surface cooling treatment, heating treatment, humidification treatment, chemical adsorption treatment, medium-effect filtration treatment and high-effect filtration treatment on fresh air. The invention further provides a fresh air purifying unit. The fresh air purifying unit is provided with an air inlet section, an initial-effect filtration section, a medium-effect filtration section, an anti-freezing preheating section, a first-level surface cooling section, a water spraying section, a second-level surface cooling section, a heating section, a humidification section, a fan section, a flow equalization section, a chemical adsorption section, a medium-effect filtration section, a high-effect filtration section and an air outlet section.

The invention discloses a safety operation method for a gaspipe network in gasometer-free single-seated blast furnace production. A blast furnace is an ironmaking blast furnace; the gaspipe network is further connected with a gas consumption unit, and connected with a low-pressure nitrogen gas pipe network through a nitrogen gas pipeline. The invention further provides a safety operation method for the gaspipe network. By adopting the technical scheme, under the situation that the pipe network is in loss of pressure, gas consumption users have time to turn off a burner valve, so as to guarantee the positive pressure of the pipe network, prevent the occurrence of back fire explosion accidents and guarantee the operation safety and stability of the pipe network. After the blast furnace obtains air again, the interior of the pipeline is always in positive pressure without the entry of air, the explosion-proof tests for blast-furnace gas consumption users are qualified within short time, and users can be guaranteed to fast resume production.

The invention relates to a novel electrical contact jack, which comprises a jack main body, a welding zone and a jack zone, wherein the jack zone and the welding zone are respectively arranged on the front end and the rear end of the jack main body, a slotting zone is formed on the jack zone along the axial direction of the jack main body, an inner cavity of the jack zone is stepwise divided into a contact zone and a longhole zone from outside in, and the inner bore size of the longhole zone is larger than that of the contact zone. The jack zone of the jack is formed by stepwise combining the contact zone with the longhole zone, the contact zone is fully utilized to realize the large-area contact of a cylinder formed when a pin is plugged in the jack, and the longhole zone is utilized to realize the correction of the concentricity deviation when the pin is plugged in the jack; the jack has a simple structure, is beneficial for the pin to be stably plugged in, and has good plug-in performance; and the service lives of the pin and the jack are prolonged.

The invention discloses a supercritical carbon dioxide positive and negative pressure interaction combined gas extraction system. The system comprises a plurality of negative pressure holes evenly formed in a coal seam wall, and positive pressure holes are formed in areas defined by adjacent negative pressure holes. An extraction pipe is arranged in each negative pressure hole, extends out of a negative pressure hole sealing device and is connected with a negative pressure branch pipe, and the negative pressure branch pipes are connected with a negative pressure main pipe; a fracturing pipe and a carbon fiber quartz electric heating pipe are arranged in each positive pressure hole, each fracturing pipe extends out of a positive pressure hole packer, and the fracturing pipes are connected with a positive pressure main pipe; the positive pressure main pipe is connected with a gas storage tank, and a heating box, a booster pump and a pressure release valve are arranged on the positive pressure main pipe between the gas storage tank and the fracturing pipe in series. The invention further discloses a corresponding gas extraction method. The energy utilization rate is high, the supercritical state of carbon dioxide can be kept for a long time, and efficient gas extraction is achieved under the interaction of positive pressure and negative pressure.

The invention provides a self-cleaning filter with an uninterrupted feeding effect. The filter comprises a shell, a plurality of filtering ring plates and a slag discharging pipe, wherein a feeding hole is formed in a side wall of the shell; a central pipe is arranged in the shell; a filtering liquid discharging hole is formed in a part, positioned outside the shell, of the central pipe; all filtering ring plates are of a circular shaped hollow cavity structure; the plurality of filtering ring plates are spaced up and down and arranged at the periphery of the central pipe in a sleeving manner; inner ring surfaces of all filtering ring plates are tightly adhered to a peripheral surface of the central pipe; material holes which are communicated with one another are formed in both of the inner ring surfaces of the filtering ring plates and the peripheral surface of the central pipe; the slag discharging pipe is positioned on one side of the central pipe; a lower end of the slag discharging pipe extends out of the shell; a slag discharging hole is formed in a part, positioned outside the shell, of the slag discharging pipe; the periphery of the slag discharging pipe is provided with a plurality of suction nozzles from top to bottom in a communication manner; each suction nozzle is positioned between two filtering ring plates which are adjacent to each other up and down; the suction nozzles are close to the filtering ring plates. According to the self-cleaning filter with the uninterrupted feeding effect disclosed by the invention, under a condition of uninterrupted charging and discharging, a self-cleaning process can be quickly completed.

The invention relates to a geothermal tail water recharge technology in geothermal exploitation and utilization process. Besides a geothermal well, the overall system mainly adopts geothermal water desanding devices, sub-catchments, a heat exchange device, frequency conversion pressurizing devices, a degassing device, a tail water filter and an electric control valve. Through the adjustment of the system, functions of the exploitation and the recharge of the geothermal well are converted, cumulative blockade caused by long term recharge of a simple opening geothermal well is eliminated, and the chronicity of the recharge is ensured; through the adoption of a standby filter, the sustainability and the continuity of the recharge process are ensured; three-level filters with different precisions are coordinated and adopted, besides, PID control with an automatic regulatory function and enabling the overall system to realize automatic frequency rising and lowering of pressure pumps and opening degree of the electric control valve is designed, and mutual interference between exploitation and recharge of the geothermal well is eliminated. The system is suitable for sandstone stratums in various areas, through the adoption of the system, economical and effective recharge can be conducted on tail water after the geothermal comprehensive utilization, and sustainable development of geothermal exploitation and utilization can be ensured.

The invention provides an auxiliary machine cooling water system achieving high-low position arrangement. The auxiliary machine cooling water system comprises multiple auxiliary machine devices sequentially arranged on the ground upwards. The multiple auxiliary machine devices are divided into the high-position arrangement auxiliary machine devices and the low-position arrangement auxiliary machine devices by a division face. An auxiliary machine dry cooling system is adopted by each of the high-position arrangement auxiliary machine devices and the low-position arrangement auxiliary machine devices. The auxiliary machine dry cooling systems comprise high-position water tanks, auxiliary machine cooling water pumps and auxiliary machine dry cooling towers. The multiple corresponding auxiliary machine devices in the high-position arrangement auxiliary machine devices and the low-position arrangement auxiliary machine devices are connected in parallel. In the high-position arrangement auxiliary machine devices or the low-position arrangement auxiliary machine devices, outlets of the auxiliary machine devices are connected with inlets of the auxiliary machine cooling water pumps, outlets of the auxiliary machine cooling water pumps are connected with inlets of the auxiliary machine dry cooling towers, outlets of the high-position water tanks are connected with the outlets of the auxiliary machine cooling water pumps, and outlets of the auxiliary machine dry cooling towers are connected with inlets of the auxiliary machine devices. By means of the system, the manufacturing requirement and cost of the devices are greatly reduced, and meanwhile the safety of device operation is improved.

The invention relates to a laser metal additive manufacturing device and method for automatically synergizing and controllable light spots and powder spots. The moving sleeve outside the barrel, the powder feeding nozzle fixed at the lower end of the moving sleeve, and the CNC workbench for placing the workpiece; the laser focusing head is used to form a spot on the workpiece processing surface through the focusing mirror; the powder feeding nozzle is used to put the powder The flow is converged and sent to the processing position to form powder spots on the workpiece processing surface; the center of the light spot and the powder spot always coincide; the CNC workbench is used to drive the workpiece to move in space relative to the focusing mirror to control the defocus distance; the moving sleeve is equipped with a driving device , the driving device is used to drive the powder feeding nozzle to move up and down through the moving sleeve to regulate the size of the powder spots. The method adopts path forming combining contour scanning and filling scanning when forming a thick and large workpiece whose cladding layer size exceeds the adjustment range.

The invention provides a kitchen air conditioner integrated machine with cabinet dehumidifying and water heating functions, belongs to the field of heating ventilation air conditioners and particularly relates to an integrated machine with the cabinet dehumidifying, kitchen cooling and water heating functions. The kitchen air conditioner integrated machine is a kitchen air conditioner system through which the problems existing in kitchen comfort, kitchen water heating and cabinet dehumidifying are solved. The kitchen air conditioner integrated machine comprises a cooling system, a water heating device, a cabinet ventilation device and a kitchen cooling device. The kitchen air conditioner integrated machine is mainly used for kitchen cabinet interior dehumidifying, kitchen water heating andkitchen temperature dropping.

The invention discloses a moistureproof distribution box with a fire power-off function, which comprises a box body assembly, a flow guide device, a separation device and a pressure regulating device, and is characterized in that the box body assembly is connected with the flow guide device, the flow guide device is communicated with the separation device, the pressure regulating device is movably connected with the box body assembly, the box body assembly is communicated with the separation device, and the box body assembly comprises a box body; a working cavity is formed in the box body, a wire inlet hole is formed in the working cavity, a wire inlet sliding groove is formed in the box body, magnetic suction cups are symmetrically arranged in the wire inlet hole, the two sides of the wire inlet sliding groove are communicated with the wire inlet hole and the working cavity respectively, the magnetic suction cup close to one side of the wire inlet hole is connected with a transmission inlet wire, and the magnetic suction cup close to one side of the wire inlet hole is connected with the wire inlet sliding groove in a sliding mode. A heat insulation layer is arranged along the inner wall of the working cavity, an air inlet channel is formed in one side of the lower end of the box body, and the flow guiding device is located at an inlet of the air inlet channel.

The embodiment of the invention discloses a cage type hyperbolic spring structure and a socket. The cage-type hyperbolic spring structure of the embodiment of the present invention is applied to the socket terminal, and the cage-type hyperbolic spring includes a plurality of copper hyperbolic column-shaped oblique springs that are circularly wound into a closed cylindrical ring structure by laser spot welding, and Machined body, the cylindrical annular spring structure is inserted into the machined body, and then the end of the thin-walled tube is riveted obliquely to ensure that the cylindrical oblique spring does not fall off during the insertion and removal of the male and female terminals. At the same time, it can also be used The method of assembly is to install an elastic C ring at the end of the thin-walled tube to compress it. In the embodiment of the present invention, the positive pressure of the male and female terminals is ensured during the mating process, which can ensure their stable contact under the condition of super high current, and each copper wire produces elastic deformation instead of plastic deformation during the compression process, which improves The service life of the product is extended, thereby prolonging the time for the spring to decay. At the same time, the hyperbolic spring structures can overlap each other during the compression process, thereby reducing the elastic deformation space of the spring, thereby ensuring a smaller volume.

The invention discloses a gas-holder-free single blast furnace produced gas pipe network. The above blast furnace is an iron making blast furnace; and the gas pipe network is connected with a gas use unit, and is also connected with a low-pressure nitrogen pipe network through a nitrogen pipeline. By adopting the above technical scheme, a burner valve can be turned off under the decompression of the pipe network of each of gas users, so the positive pressure of the pipe network is guaranteed, a back draft accident is prevented, and the safety and the stability of the running of the pipe network are guaranteed; and after the blast furnace reblowing, the pressure in the pipeline is always positive, no air enters, and the explosion-proof test of blast furnace gas users within a short time is qualified, so the rapid production recovery of the users is guaranteed.

The invention discloses a laser distance measuring sensor with a dustproof mechanism for a coal bunker. The sensor comprises a box body and an isolation body arranged in the box body, the isolation body divides the box body into an airflow channel and an inner cavity, the inner cavity is internally provided with a distance measuring machine, a power supply and a controller, the box body is provided with a display, the upper part of the airflow channel is provided with an air filter, an induced draft fan corresponding to the air filter is arranged in the airflow channel, an opening communicated with the airflow channel is formed in the lower portion of the isolation body, explosion-proof glass is arranged in the opening, a dust exhaust device corresponding to the explosion-proof glass is arranged on the lower portion of the box body, and the dust exhaust device comprises a dust exhaust window. A dustproof cover plate capable of being opened and closed is arranged on the dust exhaust window, the using is safer, the situation of pulverized coal explosion can be prevented, the dustproof cover plate capable of being opened and closed is arranged, when the sensor is not used, the dustproof cover plate can be closed in time, and interference of coal ash when the sensor is not used can be avoided.

The invention discloses a semiconductor special-purpose equipment shaft sealing structure. The semiconductor special-purpose equipment shaft sealing structure comprises an inlet dish installed on a transmission shaft and a sleeve dish arranged on the inlet dish in a sleeving mode. The contact parts of the transmission shaft, the inlet dish and the sleeve dish comprises a groove section and a spiral section. The upper part of the sleeve dish is provided with circumferential grooves. The inner side of the sleeve dish is provided with a special-shaped groove. The special-shaped groove on the sleeve dish and the groove section on the transmission shaft form an expansion cavity. The expansion cavity is filled with nitrogen to make the interior of the expansion cavity be positive pressure. The inner sides of the inlet dish and the sleeve dish and the spiral section form a throttle clearance used for hurling leaking liquid out. According to the semiconductor special-purpose equipment shaft sealing structure, multi-grade circumferential groove sealing and spiral sealing combining form sealing is adopted, the interior of the expansion cavity is filled with the nitrogen to keep the positive pressure, permeation of acidic alkaline gas and liquid is prevented, the reliability of the sealing is improved by the sealing structure , corrosion of the interior of shafting is prevented, and the service life of working of the shafting is prolonged.