109results about How to "Realize the blocking effect" patented technology

The invention provides a foaming agent for plugging gas channeling in displacement of reservoir oil by using CO2. The foaming agent is composed of the following components in percentage by weight: 0.12%-0.30% of anionic surfactant, 0.06%-0.15% of imidazoline-derived ampholytic surfactant, 0.12%-0.30% of lycine-derived ampholytic surfactant, 0.02%-0.04% of foam stabilizer and the balance of water. The foaming agent for plugging gas channeling in displacement of reservoir oil by using CO2 is characterized in that the anionic surfactant, the imidazoline-derived ampholytic surfactant, the lycine-derived ampholytic surfactant and the foam stabilizer are combined so that the obtained foaming agent is capable of forming stable foam with the CO2, and thus is strong in foaming capacity and high in stability; the foaming agent has high plugging selectivity and can be used for plugging CO2 channeling in the displacement of reservoir oil by using CO2, and therefore, the plugging effects of plugging water rather than oil and plugging large rather than small can be achieved, and the oil recovery factor and the effect of the displacement of reservoir oil by using CO2 can be improved.

The invention provides a method for growing a quantum well stress release layer of an epitaxial structure and the epitaxial structure. The epitaxial structure comprises the quantum well stress release layer with the total thickness of 160nm. The quantum well stress release layer is an HT MQW layer doped with In and Al and comprises a GaN layer with the thickness of 40nm and an AlyInxGa(1-x-y)N layer with the thickness of 2nm, wherein x ranges from 0.05 to 0.08, and y ranges from 0.02 to 0.05. According to the growing method, by modifying the energy band diagram of the HT MQW, electrons entering a luminous zone can be blocked, and the probability that the electrons enter a p layer and are recombined with holes in a nonradiative mode is reduced; moreover, the electrons blocked in the HT MQW are injected into the luminous zone more evenly through two-dimensional diffusion, the efficiency of the recombination between the electrons and the holes is promoted, and the luminance is improved.

The invention relates to extrusion forming and recycling equipment, in particular to pneumatic type waste zip-top can extrusion forming and recycling equipment for environmental protection. The pneumatic type waste zip-top can extrusion forming and recycling equipment for environmental protection can achieve automatic feeding and discharging and automatic extrusion forming. The pneumatic type waste zip-top can extrusion forming and recycling equipment for environmental protection comprises a base and a discharging mechanism, and a compression mechanism is arranged on the base; and the discharging mechanism is arranged at the lower part of the compression mechanism. An air cylinder extends to push a push rod backwards, so that an extrusion plate is pushed backwards, the extrusion plate pushes a zip-top can backwards, the zip-top can is clamped between the inner wall of the rear side of an extrusion table and the extrusion plate, and the effect of extrusion forming of the zip-top can isachieved. A first handle is manually pulled leftwards, a first baffle is subjected to leftward pulling force to enable a first sliding block to slide leftwards, a first baffle moves leftwards to drivea first fixing block to move leftwards, and the discharging effect of the zip-top can formed through extrusion is achieved.

The invention discloses a large-flux bottom mud columnar sampling device and a sampling method. The sampling device mainly comprises a suspension bracket (1), an upper connection rod (2), a cavity (4), a balance weight connection rod (6), a balance weight (7), a baffle (8), an insertion pin (9), a pulley (10), a pin control rope (11), a plate puling rope (12), a mooring rope (14), a plumb bob (15)and a sampling pipe (19). The large-flux bottom mud columnar sampling device disclosed by the invention can simultaneously realize precise layering of large-flux bottom mud samples; by the use of thelarge-flux bottom mud columnar sampling device, the shortcomings in bottom mud columnar sampling can be avoided; a technological breakthrough in the field of sample collection is realized.

The invention relates to water absorption resin for well repair and leaking stoppage. The water absorption resin is prepared by the following synthesis steps of: a, mixing 10 to 15 percent of 2-acrylamide-2-methylpropanesulfonic acid, 30 to 45 percent of acrylamide, 0.2 to 0.5 percent of N,N-methylenebisacrylamide and deionized water in a weight ratio with stirring to form a mixture, wherein the stirring time is 5 to 10 minutes and the stirring temperature is 30 to 50 DEG C; b, putting the prepared mixture into a polymerization reaction kettle, stirring the mixture, introducing nitrogen for 30 minutes to displace air in the polymerization reaction kettle, simultaneously heating the polymerization reaction kettle to the temperature of between 40 and 50 DEG C, then adding 0.03 to 0.08 weight percent of persulfate initiator into the mixture, performing polymerization reaction on the mixture to generate the water absorption resin, and preserving heat for at least 6 hours after the polymerization reaction starts; and c, drying the prepared water absorption resin at the temperature of not more than 120 DEG C for 24 hours till complete drying, and crushing the dried water absorption resin into granules with a diameter of 0.5 to 40 millimeters to obtain the water absorption resin for well repair and leaking stoppage.

The invention belongs to the technical field of municipal gardens, and relates to a drainage structure for a municipal garden. The drainage structure adopts the technical scheme that the drainage structure comprises a shaft well, a drainage pipeline, rotating plates, elastic supporting mechanisms, a vertical rod, a plurality of turning plates, elastic connecting pieces, and elastic adjusting mechanisms, wherein the drainage pipeline is connected between the bottom of the shaft well and a sewer; the rotating plates are hinged on the inner walls of the two sides of the shaft well and are symmetrical to each other; the elastic supporting mechanisms are arranged between the rotating plates and the inner walls of the shaft well and used to support the rotating plates; the vertical rod is vertically mounted at the bottom of the shaft well; the turning plates are hinged on the outer side of the top of the vertical rod; each elastic connecting piece is arranged between every two adjacent turning plates; when each turning plate is rotated to a horizontal position, the corresponding elastic connecting piece is extended, and the side of the turning plate far from the vertical rod is in contact with the corresponding inner wall of the shaft well to block sewage and impurities that pour upwards from the bottom of the shaft well; and the elastic adjusting mechanisms are arranged on the vertical rod and used to adjust the rotation angles of the turning plates. The drainage structure provided by the invention has the advantages that during use, the phenomenon that the sewage and the impurities reversely pour out of the shaft well in heavy rains can be effectively reduced, so that subsequent unnecessary troubles can be decreased.

The invention provides a gas extraction drilling convenient-injection-type hole sealing device which is mainly composed of a front baffle, a material chamber, a reaction air bag and an extrusion piston. The front baffle is fixed to the front end of the material chamber, the extrusion piston is mounted in the material chamber from the rear end in a sealed mode, and the tail end of the extrusion piston is fixedly connected with a piston rod; a penetrating hole communicating mutually and matched with an extraction pipe in outer diameter is formed in the middle of the front baffle, the material chamber, the extrusion piston and the piston rod; the extraction pipe is mounted in the penetrating hole in a sealed mode; the reaction air bag is arranged on the periphery of the material chamber, anda connecting hole communicating with the reaction air bag is formed in the position, close to the front baffle, of the bottom end of the outer wall of the material chamber; and a plug is mounted at the connecting hole, the material chamber is divided into two material chamber bodies by a partition plate mounted in the middle, and the two material chamber bodies are loaded with a polyurethane A material and a polyurethane B material. According to the gas extraction drilling convenient-injection-type hole sealing device, the hole sealing materials can react at the predetermined hole sealing position in drilled hole, the operation steps are simple, and the influence of manual operation error on the hole sealing effect can be greatly reduced.

The invention discloses a test tube shaking device, and belongs to the field of experimental equipment. A middle part of the upper end of a base is fixedly connected with a vertical plate; an output shaft fixing hole is arranged in the vertical plate; a motor output shaft of the motor is sleeved with the output shaft fixing hole; the tail end of the motor output shaft is fixedly connected with one end of a crank; the other end of the crank is fixedly connected with one end of a connecting rod, the other end of the connecting rod is connected with a connection block on a test tube clamp through a connecting bolt; a test tube is clamped in the middle of the test tube clamp; an open end of the test tube is blocked by a test tube plug; a transverse track and a longitudinal track are arranged in the vertical plate; fixed magnets are arranged at four corners of the junction of the transverse track and the longitudinal track; a reversing plate is arranged on each fixed magnet; a control box is arranged on the vertical plate. The transverse shaking or longitudinal shaking function of the test tube is achieved through the transverse track, the longitudinal track and a sliding column and the diversity of experiments is achieved.

The invention discloses a liquid crystal panel substrate and a manufacturing method of the liquid crystal panel substrate. The liquid crystal panel substrate comprises a glass substrate, a shading layer and an active layer, wherein the shading layer is arranged on the glass substrate, and the active layer is arranged on the shading layer. Due to the structure of the liquid crystal panel substrate, interference of unnecessary light sources can be reduced greatly, the problem of light leakage currents of the liquid crystal panel substrate is solved, effectiveness of the liquid crystal panel substrate is guaranteed, and the problem that frames of a liquid crystal displayer flicker or interfere with each other is solved.

The invention includes stop ends and a driving member. The said ends are two strip-type circular arc plates and the said driving member consists of two tapered lock nuts. The tapered lock nuts are slide-jointed in the T-shape groove between the stop ends and the driving member via longitudinal oblique ribs fixed in side of the strip-type circular arc plates. The frame of the inventive plugging head is two semi-circles and its diameter is the same as the diameter in the pipeline opening. The frame can stand the high pressure in the pipeline because of no plastic deformation and rigid sealing and can select to change the surface sealant materials, such as rubber, lead, luminium, copper and so on, according to the claim for pressure and temperature in the construction pipeline.

The invention discloses a precise numerical control punch forming machine for an aluminum foil meal box and a servo driving system thereof, belongs to the technical field of aluminum foil meal box processing equipment, and aims to solve the problems that when an outer cladding layer of the aluminum foil meal box is bonded, manual gluing is needed, the operation can be completed only by taking out the outer cladding layer from the punch forming machine twice, the working efficiency is greatly reduced, and the use is inconvenient. Comprising a lower stamping die and a placement bottom plate fixedly installed on the bottom face of the lower stamping die, supporting columns are fixedly welded to the top faces of the two ends of the lower stamping die correspondingly, and communicating middle columns are fixedly installed between the inner sides of the upper ends of the supporting columns in a communicating mode correspondingly; according to the automatic stamping and gluing device, the effects of stamping, gluing and pressing can be automatically completed through the device, operation is convenient and fast, manpower is saved, and meanwhile the stamping efficiency is guaranteed.

The invention relates to the technical field of beauty nourishment, in particular to a beauty freckle-removing food processing waste liquid recycling device which comprises a box-shell-shaped main box, the top of the main box is open, a waste liquid barrel is arranged in the main box, the waste liquid barrel is cylindrical, the bottom end of the barrel body is closed, and a plurality of evenly-distributed through holes are annularly formed in the barrel shell of the waste liquid barrel. The waste liquid barrel penetrates through the bottom plate of the main box, the bottom end of the waste liquid barrel is fixedly connected with an L-shaped pipe, and one end of the L-shaped pipe is fixedly connected with a supporting body. A high-quality filtering effect is achieved, after waste water in the waste liquid barrel is filtered, clear water flows into the main box, in the process that the clear water in the main box is discharged, the water level drops, buoyancy on a buoyancy ring is utilized to trigger lifting motion of an intercepting barrel, impact fluid is automatically generated in the intercepting barrel in the movement process and acts on the barrel net to impact residues attached to the outer wall of the barrel net so that the permeability of the barrel net is ensured, and preparation is made for the next filtering work of the barrel net.

The invention relates to a chamfering device, in particular to an automatic bamboo tube chamfering device for bamboo product processing. The automatic bamboo tube chamfering device for bamboo product processing is high in processing efficiency, smooth in cutting and capable of improving the cutting quality. The automatic bamboo tube chamfering device for bamboo product processing comprises two lathe beds, a discharging plate, a manual feeding assembly and a clamping assembly; and a chamfering machine is installed on the lathe bed upper portion at the right side of one lathe bed; the discharging plate is connected between the lower parts of the two lathe beds; the manual feeding assembly is arranged between the upper parts of the two lathe beds; and the clamping assembly is arranged on the manual feeding assembly. According to the automatic bamboo tube chamfering device for bamboo product processing, a bamboo tube is placed on a workbench, a grab handle is loosened, and a first compression spring is reset, so that the workbench is driven to move rightwards, and the feeding effect is achieved; and by loosening clamping blocks, first telescopic rods are reset, so that second baffles are driven to move oppositely, then the clamping blocks are driven to move oppositely, the bamboo tube is clamped, and the clamping effect is achieved.

The invention belongs to the technical field of oil exploitation, and particularly relates to an oil leakage collecting device for offshore oil exploitation. According to the problem that seabed oil and sea oil cannot be effectively collected at the same time by an existing oil leakage collecting device, the following scheme is provided, the oil leakage collecting device comprises a supporting plate, a first groove is formed in the outer wall of the middle of the top of the supporting plate, and the inner wall of the first groove is connected with a vertically-arranged connecting pipe througha bearing; and a second groove is formed in the outer wall of the middle of the bottom of the supporting plate, and the inner wall of the second groove is connected with a vertically-arranged second oil guide pipe through a bolt. In the oil leakage collecting device for offshore oil exploitation, through the arrangement of a conic block, when oil is sprayed into a second oil gathering pipe from atable pipe through centrifugal force and extrusion, the conic block can achieve the stop function on the oil, after being attached to the conic block, the oil can flow into an arc guide pipe, then theoil flows into an oil storage box through third oil guide pipes, and recovery to sea oil is achieved.

The invention discloses an illumination simulation method and device in a virtual scene and electronic equipment. The method comprises the steps that illumination parameters of a light source in a preset area in the current virtual scene are acquired; according to the illumination direction in the illumination parameters, illumination detection is carried out on the preset area, a target area in the preset area is obtained, and the target area is an area where light is shielded; according to state information of a virtual object in the target area, a corresponding target material is obtained from a material library, the state information is used for indicating that the virtual object is in a light shielding state, and the target material does not contain an illumination algorithm generated for the illumination parameters; and the virtual object is rendered according to the target material.

The invention discloses multilayered filtering equipment with a backwashing device. The external structure of the multilayered filtering equipment mainly comprises a barrel, a feeding pipe, a discharge pipe, a support and a waste residue outlet, wherein a three-layered filter material layer is arranged inside the barrel, in which a perlite layer serves as the lower layer, a quartz sand layer serves as the interlayer, and an activated carbon layer serves as the top most layer; the particle size of the filter material is gradually reduced to increase the filtration efficiency. In the multilayered filtering equipment disclosed by the invention, a control valve is used to switch between the filtering function and the backwashing function; during the filtering process, the material liquid is fed from a lower feeding hole and discharged from an upper discharge hole; during the backwashing process, the material liquid is fed from the upper feeding hole and discharged from the lower discharge hole; the fed material is uniformly distributed through a distribution pipe and the baffling action of a baffle plate, and meanwhile the impact on the filter material when the fed material flows too much can be relieved; the baffle plate serves as a reversed U shape, so as to effectively realize the baffling effect; an access hole is formed in the side of the barrel to bring convenience to inspection; an overflow weir is used to discharge the material, so as to facilitate the discharged material to be more uniform.

The invention belongs to the technical field of power distribution boxes, and discloses an outdoor energy-saving power distribution box for solving the problem that in existing power distribution boxes, energy consumption is high due to adoption of heat dissipation fans for heat dissipation. The power distribution box includes a box body, the cross section of the lower portion of the box body is rectangular, the cross section of the upper portion of the box body is circular, the upper end of the box body is provided with a supporting frame, the center of the supporting frame is provided with abearing base, a rotating shaft is sleeved with the bearing base, the upper end of the rotating shaft is connected with a top shed composed of a bracket and side plates which are connected on the bracket in an inversely Y-shaped mode, the side plates are provided with multiple venting pipes, the venting pipes include the first venting pipes and the second venting pipes, the first venting pipes areobliquely arranged upwards on the side plates, the second venting pipes are vertically arranged, and the first venting pipes are communicated with the second venting pipes; the upper end of the top shed is connected with a wind shielding device for driving the top shed to rotate on the bearing base, and the lower portion of the box body is provided with a ventilator.

The invention discloses a beverage bottle passage door device. A door body is driven by a power unit and a transmission unit to move reciprocally on a door frame, so as to open or close a passage window; a trigger sensor and a trigger part are matched to limit the sliding of the door body, so as to ensure that the passage window is kept to be opened to the maximum state under the passing state, orthe passage window is kept to be closed tightly under the blocking state; and a light curtain sensor is arranged at the upstream of the door body, the accidents of hand pinching and the like can be prevented, the overall safety performance is improved, the light curtain sensor can further be used for detecting whether passing of beverage bottles is finished or not, so as to close the passage window in time. The beverage bottle passage door device is used in the beverage bottle recovery machine, thus users can be prevented from conducting improper operation and damaging the beverage bottle recovery machine or making improper profits; and the users can further be protected from being injured by splashing beverage bottle fragments, and the safety of the users during using is ensured.

The invention relates to a stripping device, in particular to an agricultural extrusion type garlic granule stripping device. The agricultural extrusion type garlic granule stripping device provided by the invention has the advantages that garlic cloves are thoroughly extruded, and automatic material control and automatic material discharging are realized. An agricultural extrusion type garlic granule stripping device comprises a base, wherein an extrusion mechanism is arranged on the front side of the base; and a material control mechanism arranged on the rear side of the base. A cylinder telescopic rod drives a push block to move downwards, so that a pressing plate is driven to move downwards, the pressing plate makes contact with garlic cloves, the pressing plate extrudes the garlic cloves, the garlic cloves are extruded into garlic granules, and the extrusion effect is achieved; the second telescopic assembly drives the material blocking plate to move downwards, the material blocking plate makes contact with the base, the second telescopic assembly is compressed, the material blocking plate blocks the discharging opening of the base, garlic granules on the base are blocked, and the material blocking effect is achieved.

The invention discloses a stacked filter. The stacked filter comprises a filter body, an oil way cover plate and a filter element; the filter body is installed between a valve station and a plate type hydraulic valve, the oil way cover plate is detachably installed on the filter body, the filter body is provided with a filter element cavity, the filter element is arranged in the filter element cavity, a main oil passage is arranged in the filter body and is communicated with the filter element cavity, and a medium entering the main oil passage is led to the outer side of the filter element in the filter element cavity; a filter oil inlet is formed in one side surface of the filter body, a filter oil outlet is formed in the other side surface of the filter body, the filter oil inlet is communicated with the main oil passage, and the filter oil outlet is communicated with the filter element cavity through an oil way in the oil way cover plate. The stacked filter locally filters a control valve with higher precision requirements to form local protection under the condition that the filtering precision of the main oil passage is not high and the filtering reliability is not enough, so that the service lives of equipment and a system are prolonged.

The invention provides a method for growing a quantum well stress release layer of an epitaxial structure and the epitaxial structure. The epitaxial structure comprises the quantum well stress release layer with the total thickness of 160nm. The quantum well stress release layer is an HT MQW layer doped with In and Al and comprises a GaN layer with the thickness of 40nm and an AlyInxGa(1-x-y)N layer with the thickness of 2nm, wherein x ranges from 0.05 to 0.08, and y ranges from 0.02 to 0.05. According to the growing method, by modifying the energy band diagram of the HT MQW, electrons entering a luminous zone can be blocked, and the probability that the electrons enter a p layer and are recombined with holes in a nonradiative mode is reduced; moreover, the electrons blocked in the HT MQW are injected into the luminous zone more evenly through two-dimensional diffusion, the efficiency of the recombination between the electrons and the holes is promoted, and the luminance is improved.

The invention discloses a bronchial spraying freezing system. The system comprises a pipe body, a spraying head, a flow-choking sheet, and a cold source apparatus, wherein the cold source apparatus, the pipe body, and the spraying head are connected in order, the spraying head comprises a plurality of spraying ports and a head end, the spray ports are circumferentially and uniformly distributed inthe middle of the spraying head, the flow-choking sheet is located between the spraying ports and the head end, and the flow-choking sheet covered on the surface of the spraying head can be unfoldedto realize distal end plugging. The flow-choking sheet is a ring-shaped circumferential flexible material, an axial section along a vacuum pipe is S-shaped or arc-shaped, and an unfolded shape of theflow-choking sheet is formed by a cold source fluid sprayed from the spraying ports, or a pushing apparatus to achieve flow-choking effects. Therefore, the bronchial spraying freezing system is provided with the flow-choking sheet at the distal end of the spraying ports, the distal end plugging is realized, at the same time, self-adaptive adjustment for plugging areas with different sizes can be performed, plugging effects of the plugging areas with different sizes are realized, and thereby a safe and convenient mean for treating airway hyper-responsiveness or chronic bronchitis is provided.

The invention discloses a carbon fiber hot press molding densification technology and equipment, and belongs to the technical field of carbon fiber processing, the technology comprises raw material mixing, layer laying, hot press molding, high temperature curing carbonization, demolding, asphalt dipping, carbonization, naphthalene in-situ asphalt dipping polymerization, high temperature and high pressure carbonization, graphitization and surface coating; the equipment comprises a V-shaped stirring machine and a hot pressing mold, feeding ports are formed in the tops of feeding channels on the two sides of a V-shaped stirring barrel, a discharging port is formed in the bottom of the V-shaped stirring barrel, a baffle is hinged to an upper wall plate of the V-shaped stirring barrel, a check block is arranged on a lower wall plate of the V-shaped stirring barrel, and a scraper assembly is arranged on the lower wall plate; a stirring assembly is arranged above a discharge hole of the V-shaped stirring barrel; the hot pressing mold comprises a mounting frame, an upper heating part is arranged below a top plate of the mounting frame, a carbon-carbon upper mold is arranged below the upper heating part, a carbon-carbon lower mold is arranged below the carbon-carbon upper mold, a lower heating part is arranged below the carbon-carbon lower mold, and a jacking air cylinder is arranged below the carbon-carbon lower mold.

The invention mainly discloses a NMP filter. According to a technical scheme in the invention, the NMP filter comprises an exhaust gas pipe, a cooling pipe, a separation pipe and an exhaust elbow, wherein the cooling pipe sleeves and is fixed on the exhaust gas pipe; a cooling channel is formed between the cooling pipe and the exhaust gas pipe; the separation pipe is communicated with the exhaust gas pipe and fixedly connected with the exhaust elbow; one end of the exhaust elbow extends out of the separation pipe, and the other end of the exhaust elbow is located in the separation pipe; the bottom of the separation pipe is provided with a drain outlet; the cooling pipe is separately provided with a cold air inlet and a cold air outlet; and the cold air inlet is connected with a vortex tube. The NMP filter provided by the invention is simple in structure, condenses NMP gas in exhaust gas into liquid through low-temperature cooling, and realizes gas-liquid separation and exhaust gas emission without pollution.

The blocking device of gantry crane includes one connecting board with two welded ears, two clamping plates connected to the connecting board via the ears, one feed-through shaft stretched beyond the clamping plates, two rotary forks, one upper hydraulic ram connected to one of the rotary forks, one swinging leg connected to the other rotary fork, one fixed shaft penetrating through the swinging leg to the clamping plates, and blocking shoes in the shape fitting the track and the track wheel and connected via a shaft to the swinging leg. During use, the connecting board is fixed in the front of the track wheel, the blocking shoes are stretched below the track wheel and the rotary fork is rotated with the hydraulic ram, so that the swinging leg is lifted off the track and the track wheel for normal running while avoid wind driven sliding.

The invention discloses a seedling raising device for flower seedlings. The seedling raising device comprises a seed separating mechanism and a soil covering mechanism; the seed separating mechanism comprises an outer shell; clamping plates are fixedly connected with the two ends of the outer shell; handle rods are clamped to the surfaces of the clamping plates; connecting sleeves are fixedly connected with the side faces of the handle rods; guide rods are slidably connected with the inner walls of the connecting sleeves; a bottom plate is fixedly connected with the bottom ends of the guide rods; a shifting column is fixedly connected with the upper surface of the bottom plate; a seed box communicated with the interior of the outer shell is clamped to the upper surface of the outer shell; a movable plate sliding left and right is slidably connected with the inner wall of the outer shell; and a reset spring and a transmission frame are fixedly connected with the two ends of the movable plate respectively. According to the seedling raising device for the flower seedlings, the movable plate slides left and right in a reciprocating mode, seeds with the same volume or number can be fed into a connecting pipe, a soil inserting device is opened after being inserted into soil, and the seeds automatically fall into the soil, so that sowing is uniform, the number is controllable, and the sowing quality and the speed are greatly improved.

The invention discloses a road and bridge construction technology. A large-span bridge gantry crane comprises temporary track bridges arranged on the two sides of an existing river-crossing bridge, sliding tracks are arranged on the temporary track bridges, the large-span bridge gantry crane further comprises a gantry crane portal frame arranged above the existing river-crossing bridge, supportinglegs are connected to the lower portion of the gantry crane portal frame, and sliding groove bases corresponding to the sliding tracks are arranged at the lower ends of the supporting legs. The large-span bridge gantry crane ingeniously starts from the construction angle, gantry crane equipment is arranged above an existing river-crossing bridge, hoisting operation is easily achieved, precise hoisting equipment is provided for widening or dismantling or maintaining construction of the existing river-crossing bridge, and the wading construction precision of the equipment is guaranteed.

The invention relates to a pressure blocking device for underground pressurized operation. The device is used for realizing a temporary pressure blocking effect when the pressurized maintenance operation is carried out underground, breaking a central block after workover operation is completed, and enabling a shaft to be smooth. The device is simple in structure and convenient to implement and iscomposed of six parts: an expansion ring, a central pipe, a cone, a slips, a tension rod and a push ring. The tension rod is separated from the pressure blocking device after setting of the pressure blocking device and can be brought away from a well site, the expansion ring is expanded under force to achieve a blocking effect, manufacturing materials are manufactured from soluble metal materials(or soluble non-metal materials), and can be used at high temperature and high salinity, the pressure blocking device can achieve blocking removal through self-dissolution or human intervention, blocking can be achieved in advance through pressurizing the interior of a well through human intervention, the required pressure is small, and the influence on subsequent construction is small.

The present invention relates to the technical field of nuts, and specifically discloses an anti-theft nut, which includes a nut body and a hexagonal angle piece. A metal convex plate is formed, and the top of the metal convex plate and the positions close to the left and right sides of the nut body are provided with card slots. Through the structural design of the nut body, hexagonal corner fasteners, metal convex plate, card slots and slots , so that the nut body can only be rotated and twisted through the protruding rod of a specified shape, and through the flexible connection between the nut body and the hexagonal corner piece, it is difficult for the thief to find the position of the blocking metal block. Through the structural design of the clamping slot and the blocking metal clamping block, the clamping slot is effectively blocked, and through these structural designs and cooperation, the nut has an anti-theft effect effectively.