44results about How to "Improve pumping efficiency" patented technology

The utility model relates to the technical field of casting, in particular to a vacuum negative pressure device for lost foam casting. According to the technical scheme, the device comprises a mounting bottom plate, a vacuum pump is arranged above the mounting bottom plate, a pressure stabilizing assembly is arranged at the position, located on the mounting bottom plate, of the air inlet end of the vacuum pump, a filtering assembly is arranged on one side of the pressure stabilizing assembly, a negative pressure pipe is arranged on a connecting pipe, and a vacuum distribution mechanism is arranged at the end, away from the connecting pipe, of the negative pressure pipe. The filtering assembly adopts a multi-layer composite filtering structure, so that impurities in gas can be efficiently removed, meanwhile, the system pressure can be monitored and adjusted in real time through an intelligent central controller in the pressure stabilizing assembly, pressure fluctuation is effectively buffered, a stable negative pressure environment is provided for lost foam casting, and the production efficiency is improved. And meanwhile, the vacuum distribution mechanism is designed in a modularized mode, negative pressure distribution can be accurately controlled according to different production requirements, the air exhaust efficiency is improved, and the production efficiency of lost foam casting and the precision of castings can be improved.

The present application relates to the technical field of plunger pump, in particular to a variable stroke double cavity plunger pump, which comprises a shell and a driving motor, two delivery pipes are arranged in the shell, two groups of crankshaft assemblies are arranged on the output shaft of the driving motor, the shell is connected with the corresponding delivery pipe through the crankshaft assembly, and a first one-way valve and a second one-way valve are symmetrically arranged in the delivery pipe along the axis of the crankshaft assembly; the one-way valve comprises a reset assembly, a sealing assembly and a clamping assembly arranged in sequence from top to bottom, the sealing of the sealing assembly is realized by the elastic extension of the reset assembly and the adhesion of the clamping assembly; the sealing assembly on the first one-way valve is provided with a first negative pressure assembly, the sealing assembly on the second one-way valve is provided with a second negative pressure assembly, and the first negative pressure assembly and the second negative pressure assembly are oppositely arranged; by arranging the negative pressure disc and the connecting pipe, the stress area of the sealing ball under the negative pressure condition is increased, the opening speed is accelerated, and the fluid passing efficiency is improved.

This utility model relates to the field of vacuum pump technology and discloses a vacuum pump assembly, including a housing, a first vacuum pump and a second vacuum pump arranged inside the housing, the second vacuum pump being located directly below the first vacuum pump, the inlet end of the first vacuum pump passing through the housing and communicating with the outside, the outlet end of the first vacuum pump being connected to the inlet end of the second vacuum pump, and also including a silencing unit, the silencing unit being attached inside the housing and located directly below the second vacuum pump, one end of the silencing unit being connected to the outlet end of the second vacuum pump, and the other end communicating with the outside. This utility model, with the first vacuum pump, the second vacuum pump, and the silencing unit sequentially located directly above their respective units, has a compact structure and improves space utilization.

The utility model provides a kind of vacuum bag type packaging sealing device, comprising: support;Workbench, it is fixedly installed on support upper end;Positioning plate, it is fixedly installed on support one side;Sealing group, it is set in workbench upper end;Limiting group, it is set in positioning plate one side.This kind of vacuum bag type packaging sealing device, by setting limiting group and the like structure, limiting group is conveniently operated by hydraulic rod, cooperate through-hole and connecting pipe, improve the efficiency of air extraction and connection stability, also have strong versatility;Heating plate can be detached in sealing group, it is convenient to maintain replacement, heating pipe and sealing plate cooperation realize reliable heat sealing, support rod guarantee pressing plate stability, electric telescopic rod realizes automatic sealing, reduce labor intensity, overall device is efficient, convenient, stable, can guarantee vacuum packaging quality, suitable for a variety of vacuum bag, improve the efficiency and reliability of packaging work.

The utility model relates to fire engineering technical field, concretely is a kind of emergency drainage device for fire-fighting equipment, including base, one floating plate is respectively installed in the both sides of base by pivot, the side of floating plate is equipped with mounting groove, the inside installation of mounting groove has air bag, the top of base is fixed with waterproof control box, one inflation telescopic pipe is respectively communicated in the both sides of waterproof control box, one end of inflation telescopic pipe extends into mounting groove inside and is connected with air bag inside.The utility model can drive two floating plates to deflect by the extension of two first cylinder output ends, so that the air bag installed in the side of floating plate is contacted with water surface, then the inflator installed in waterproof control box inside fills gas into the inside of air bag by inflation telescopic pipe, so that air bag volume expands, so that two air bags produce buoyancy and make the whole device float on water surface, avoid device to be submerged by accumulated water and appear fault when using, improve pumping efficiency.

The invention relates to the technical field of diaphragm pumps, in particular to a high-temperature-resistant single-runner diaphragm chamber which comprises a cooling pipe section, a diaphragm cavity and a diaphragm chamber gland installed on the diaphragm cavity, a diaphragm chamber is formed between the diaphragm chamber gland and the diaphragm cavity, and the two ends of the cooling pipe section are a high-temperature slurry end and a low-temperature slurry end respectively. The diaphragm cavity is provided with a feeding hole through which cooled slurry can enter or flow out of the diaphragm chamber from the bottom of the diaphragm chamber, the low-temperature slurry end is communicated to the feeding hole in the diaphragm chamber, and the high-temperature slurry end is used for receiving uncooled slurry; according to the diaphragm pump, on the premise that the form of the high-temperature slurry is not changed, direct pumping of the high-temperature and strong-corrosion slurry can be achieved, meanwhile, the effect of the high-temperature and strong-corrosion slurry on the diaphragm is effectively reduced, it is avoided that the diaphragm rapidly loses efficacy due to overtemperature and corrosion, and it is guaranteed that the diaphragm pump stably operates for a long time under the high-temperature and strong-corrosion working condition.

This utility model provides a filtration device for a laminator, relating to the field of laminator filtration technology. It aims to solve the problems of poor filtration efficiency in existing vacuum pumps that use conventional paper filter elements to filter the gas generated during vacuuming. This allows impurities such as welding slag and iron filings to penetrate the filter element and enter the vacuum pump cavity, affecting normal operation. Furthermore, the accumulation of impurities and dust necessitates frequent inspection, maintenance, and upkeep of the vacuum pump and filter, increasing maintenance costs. The proposed device includes a vacuum pump system with a laminator vacuum valve installed on its left side. A filter tank system is installed between the vacuum pump system and the laminator vacuum valve. The tank serves as a pre-vacuum tank to pre-vacuum the cavity. A bypass design is used; after pre-vacuuming, the filter tank's function is disabled, and the pump directly evacuates the cavity, reducing pump load, effectively improving equipment evacuation efficiency, reducing vacuum pump filter consumption, and minimizing pump maintenance.

The application provides an internal-pumping thin slice laser emitting coherent array laser, comprising a heat sink, a pump light source, a coupling module, an internal resonant cavity and a cut-angle external cavity, the internal resonant cavity, the cut-angle external cavity and a double-wavelength reflecting layer arranged outside a front end surface of the cut-angle external cavity form a resonant cavity, the internal resonant cavity comprises, from inside the cut-angle external cavity, a semi-reflective semi-transmissive layer, a micro-structure thin slice and a double-wavelength high-reflective layer arranged in sequence from the inside of the front end surface to a rear end surface, and the double-wavelength high-reflective layer and the rear end surface of the cut-angle external cavity are attached to the heat sink. The internal-pumping thin slice laser emitting coherent array laser has the advantages of high pumping efficiency, output power, beam quality and stability, and compact structure. The application further provides a preparation method of the internal-pumping thin slice laser emitting coherent array laser.

The utility model relates to the technical field of flood prevention pumps, and discloses a large-flow flood prevention pump suitable for a narrow space, which comprises a shell, a water pumping mechanism is arranged in the shell, the water pumping mechanism is used for pumping water, a supporting mechanism is arranged at the bottom of the shell, the supporting mechanism is used for supporting equipment, the water pumping mechanism comprises a first motor, and a second motor is arranged at the bottom of the shell. The first motor is fixed to the outer wall of the shell, the output end of the first motor penetrates through the outer wall of the shell and is fixedly connected with a center shaft, an outer layer assembly is arranged on the outer wall of the center shaft, inner fan blades are arranged on the inner wall of the outer layer assembly, a water inlet assembly is arranged on the outer wall of the shell, and a water outlet assembly is arranged at one end of the shell. According to the utility model, basic flow is provided through the outer-layer large-diameter blades, suction force is enhanced through the inner-layer small-diameter inner fan blades, the water pumping efficiency is greatly improved, an external water pipe is put into an area to be pumped for water pumping, and operation in a narrow space is facilitated.

This utility model relates to the field of vacuum pump technology, specifically a reciprocating vacuum pump. It includes: a first housing with an inlet and an outlet; a first cavity formed on the first housing and connected to the inlet; a second cavity formed on the first housing and connected to the outlet; a valve plate located at the lower end of the first housing and equipped with a one-way valve; a second housing located at the lower end of the valve plate and equipped with a third cavity and a fourth cavity; the third cavity is connected to the first and second cavities via a one-way valve, and the fourth cavity is connected to the first and second cavities via a one-way valve. A cylindrical cavity is provided inside the second housing, with its two ends connected to the third and fourth cavities respectively, and a piston is slidably disposed within the cylindrical cavity. A rotatable crank and a slidable slide rod are provided inside the second housing, with a connecting rod between the crank and the slide rod, and the slide rod connected to the piston. The reciprocating motion of the piston can generate a vacuum, resulting in higher working efficiency.

The invention relates to the technical field of lasers, and discloses a nanosecond ultraviolet laser packaged by a semiconductor laser diode in an optical cavity. Comprising an optical cavity, a first plano-convex mirror, a gain medium, a Q-switched device, a second plano-convex mirror, a frequency doubling crystal, a frequency tripling crystal and a reflector. A plurality of semiconductor laser diodes, a micro-lens array and an optical fiber are arranged in the optical cavity. According to the nanosecond ultraviolet laser packaged by the semiconductor laser diode in the optical cavity, through the semiconductor laser diode packaging structure in the optical cavity and the design of the resonant cavity, the pumping efficiency of the laser is improved, high-power ultraviolet light output is further achieved, and meanwhile the stability and the structural compactness of the laser are improved.

The application discloses a kind of high density low rebound shotcrete and preparation method thereof, it is related to shotcrete field, and preparation method includes: (1), respectively to cementitious material, fine aggregate, coarse aggregate is using MAA model to be packed and the design ratio of each raw material in interior is obtained;(2), cementitious material, fine aggregate, coarse aggregate and the rebounding agent of design ratio obtained according to step (1) are fully mixed, water, water reducing agent is mixed, then by the way of mixing with pressurized air, incorporate accelerator, obtain high density low rebound shotcrete.The application uses early strength rebounding agent, improves the pumpability of shotcrete, accelerates the early hydration of concrete, under the joint action of alkali-free accelerator, rapidly improves the early mechanical properties of shotcrete, improves shotcrete construction efficiency.Multiple close packing is used, and cementitious material, fine aggregate, coarse aggregate respectively form close packing structure, effectively improve the plastic viscosity of paste and the compactness of concrete.

This utility model relates to the field of pump station technology, and in particular to an integrated FRP (fiberglass reinforced plastic) gate-controlled pump station. It includes a debris-blocking mesh plate slidably connected to the inner wall of the inlet of the water inlet channel. The outlet of the water inlet channel is located on one side of the bottom of the FRP cylinder. A flow-guiding base is provided in the middle of the bottom wall of the FRP cylinder, and a pumping mechanism is vertically inserted through the middle of the top of the flow-guiding base. A fence is provided along the outer edge of the top of the FRP cylinder. An inlet gate is slidably connected to the inner wall of the inlet of the water inlet channel located directly behind the debris-blocking mesh plate. A battery is provided on one side of the top of the flow-guiding base. The debris-blocking mesh plate in this device can filter impurities, and its fluororubber sealing layer prevents leakage. The connecting channel guides water flow to the inverted conical flow-guiding base, reducing resistance and concentrating water flow for improved efficiency. The submersible pump in the pumping mechanism pumps and pressurizes water, and its gate valve adjusts flow rate and pressure for energy saving. The FRP cylinder ladder, entrance, and landing facilitate maintenance, and the fence provides safety protection.

The utility model relates to the technical field of mechanical parts, in particular to a plunger pump assembly, which comprises a pump body, a return spring, a return spring seat and a plunger sleeve, a first cavity and a second cavity are arranged in the pump body, the first cavity is communicated with the second cavity, and the first cavity is communicated with the second cavity. The bottom in the second cavity is sleeved with a plunger sleeve, and a return spring is installed at the bottom in the plunger sleeve through a return spring seat. An oil pump blocking assembly is clamped to the top of the first cavity, a steel ball is arranged in the first cavity, and an oil stop spring is clamped between the steel ball and the oil pump blocking assembly. The plunger pump assembly achieves the working process of continuous oil pumping, stability is high, the effect is outstanding, the one-way valve is designed to prevent oil return, and the oil pumping efficiency is improved.

This invention relates to the field of air conditioning technology, specifically to a fresh air module and a fresh air air conditioner. The fresh air module includes a fan, a first chamber, and a second chamber. The first chamber is connected to the air inlet of the fan, and the second chamber is connected to the air outlet of the fan. The first chamber has a fresh air inlet and a first stale air inlet, and the second chamber has a fresh air outlet and a stale air outlet. Both the fresh air outlet and the first stale air inlet are connected to the interior, and both the fresh air inlet and the stale air outlet are connected to the exterior. A second stale air inlet is located on the side wall of the fresh air outlet and is connected to the first chamber. Valves are provided at the inner end of the fresh air outlet, the fresh air inlet, the first stale air inlet, the stale air outlet, and the second stale air inlet. The fresh air module and fresh air air conditioner provided by this invention have high extraction efficiency, fast indoor air renewal speed, excellent exhaust effect, reasonable structural space utilization, and are more aesthetically pleasing.

This utility model discloses a microwave plasma etching machine structure, including a main body, a vacuum pumping device mounted on the main body, a sealing cover mounted on top of the main body, a top cover mounted on top of the sealing cover, multiple gas nozzles mounted around the top cover, a hot gas treatment device mounted below the gas nozzles, and a wafer carrier device mounted below the hot gas treatment device. This microwave plasma etching machine structure features a vacuum pumping device with a pressure relief valve at the pumping port to prevent overpressure and an efficient and stable pumping pipe; a hot gas treatment device with an annular heat exchange tube at the outer shell's ventilation port for heat exchange and a gas guide base to assist in hot gas treatment; a wafer carrier device with electrostatic adsorption to stably hold the wafer below the carrier platform and a cooling device for temperature control and liquid drainage; rotatable and angle-adjustable gas nozzles that flexibly adjust the spray direction and angle according to the process and size to improve etching accuracy; and a double-walled structure for the main body, with an outer layer of high-strength metal and an inner layer of corrosion-resistant and wear-resistant material to extend the equipment's lifespan.

The utility model discloses a hydrogen peroxide production line combined vacuum-pumping system, which is characterized in that a vacuum-pumping main pipe outlet is connected with an extraction opening of a roots vacuum pump, an exhaust opening of the roots vacuum pump is connected with an extraction opening of a liquid ring vacuum pump in series, and an exhaust opening of the liquid ring vacuum pump is connected with a gas inlet at the top of the left side of a gas-liquid separation tank; a right top exhaust port of the gas-liquid separation tank is connected with a tail gas collection device; a vertical middle partition plate is arranged in an inner cavity of the gas-liquid separation tank and divides a tank body into a left cavity and a right cavity, and an overflow channel is reserved between the middle partition plate and the tank top. A pure water replenishing pipe is connected to the left cavity of the gas-liquid separation tank through a pure water replenishing valve; a water outlet in the lower part of the left cavity of the gas-liquid separation tank is connected with a hot side inlet of a cooler through a filter; a hot side outlet of the cooler is connected with a working liquid inlet of a liquid ring vacuum pump; and a water outlet at the bottom of the right cavity of the gas-liquid separation tank is connected with a wastewater discharge pipe through a wastewater discharge valve. According to the system, the vacuum degree and the air exhaust efficiency can be improved, automatic adjustment of the vacuum degree and automatic separation and discharge of waste liquid are achieved, and meanwhile energy consumption is reduced.

The utility model relates to a sealing detection device for an automobile headlamp, which belongs to the field of automobile headlamp detection and comprises a detection box body, a pressure sensor fixedly communicated with the inside of the detection box body and extending to the outside of the detection box body, a stand column fixedly connected to the top of the detection box body and a mounting plate fixedly connected to the top end of the stand column. A limiting mechanism for limiting and fixing the headlamp is arranged on the upper surface of the detection box body, and a negative pressure generation structure is arranged outside the detection box body. According to the sealing performance detection device of the automobile headlamp, the output end of the electric push rod drives the partition plate to move downwards in the detection box body to limit and fix the headlamp, the partition plate is connected with the linkage structure through the fixing rod and the rack, so that the piston plate is driven to reciprocate through the rotating disc and the connecting rod, and a negative pressure environment is formed in the detection box body; the risk of damage to the internal structure and the sealing material of the headlamp due to overlarge internal pressure is fundamentally eliminated, and the advantage of nondestructive testing is achieved.

This utility model discloses a foundation pit drainage device for building construction, comprising: a deep foundation pit; a foundation pit pumping assembly mounted on the deep foundation pit, the foundation pit pumping assembly being used for pumping and draining water; and a sludge preliminary sedimentation and removal assembly mounted on one side of the foundation pit pumping assembly. The device performs secondary deep filtration of the water through a second filter plate to further remove residual impurities. A water level detector monitors the water level in real time to ensure stable filtration. The filtered water is discharged into a drainage ditch via a drainage pipe through a pump. If sludge is generated during filtration, a second sludge suction pipe transports it to a sludge pump for discharge. The advantages of this device are that the secondary filtration assembly further improves water quality, reduces impurities from clogging the drainage system, and improves drainage efficiency and quality. Simultaneously, the water level detector enables automated monitoring, improves the system's intelligence level, reduces manual intervention, and further optimizes the drainage effect.

This invention provides a composite cementitious material with high rheological properties, its preparation method, and concrete, comprising an active admixture, 40%–60% ordinary Portland cement, 20%–35% modified marble powder, and 0.8%–2% functional admixtures. The modified marble powder is obtained by surface modification treatment of marble powder with a silane coupling agent and a polycarboxylate superplasticizer, effectively solving the problem of marble powder agglomeration and ensuring uniform dispersion in the cementitious system. This significantly optimizes the rheological properties of the paste, improving fluidity and pumpability. The synergistic effect of cellulose ether and air-entraining agent in the functional admixtures further enhances the material's water retention and anti-segregation stability. The cementitious material prepared by this invention possesses both excellent mechanical properties and durability, and the concrete prepared with it exhibits good workability, dense structure, and reliable long-term performance. Simultaneously, this technology achieves high-value-added resource utilization of marble waste, reduces cement consumption and carbon emissions, and aligns with the direction of green building materials and sustainable development.

The invention discloses a pipeline-free extensible magnetic rotor micropump chip in the field of micro-fluidic chips, and the chip comprises a cover plate layer, the bottom surface of which is provided with a medium channel; the substrate layer is fixedly arranged at the bottom of the channel layer and is used for closing the bottom of the medium channel and supporting the channel layer; the micro-rotor is rotationally clamped in the medium channel so as to rotate at a fixed position in the medium channel, and the micro-rotor rotates through the change of an external magnetic field so as to pump fluid in the medium channel; the micro-rotor pump has the beneficial effects that the micro-rotor is arranged in the circulation channel, the micro-rotor can be controlled to rotate through external magnetic field changes to achieve pumping of fluid media in the medium channel, redundant structures and lines do not exist in the medium channel, dependence on the external structure is lower, the pumping efficiency is improved, and the structure is simpler.

This application relates to a delivery tube, a cannula assembly, and a blood pump. The delivery tube is hollow and has an inner wall surface, an outer wall surface, and a blood passage through the inner and outer wall surfaces. The delivery tube also has a wall defining the blood passage, with its inner edge connected to the inner wall surface and its outer edge connected to the outer wall surface. At least a portion of the wall is arc-shaped from its inner edge to its outer edge, and the center of the arc-shaped circle of the at least portion of the wall is located between the inner and outer wall surfaces. The delivery tube of this application not only reduces damage to blood flowing through various areas of the delivery tube, thus minimizing the negative impact of the blood pump on human health during use, but also improves pumping efficiency.

This invention discloses a low-carbon, high-density shotcrete admixture, its preparation method, and its application, relating to the field of concrete admixtures in building materials. The admixture comprises the following components by mass percentage: 53-73% rheological component, 15-25% thickening component, 10-18% early-strength component, and 0.5-4% setting regulator component. The rheological component includes manganese slag powder and silica fume, and the thickening component is tailings powder loaded with nano-modified cellulose ether. This invention increases the cohesiveness of shotcrete and improves the slurry encapsulation of concrete through the thickening component, increases the yield stress of concrete through the rheological component, and synergistically improves the adhesion and rapid hardening performance of the material after spraying by combining with the early-strength component, thereby reducing the rebound rate. Furthermore, the nanoparticles loaded on organic matter hydrate in the pores, directionally filling harmful pores, effectively improving the density and strength of shotcrete, achieving low-carbon, low-rebound, and high-density shotcrete.

The utility model relates to the technical field of ventilation, and provides a metal mine underground ventilation device which comprises a ventilation pipe (1), an inner pipe (2) is arranged in the ventilation pipe (1) in a sliding mode, an air draft mechanism (3) is arranged in the inner pipe (2), a lifting mechanism (4) is arranged between the inner pipe (2) and the ventilation pipe (1), and a spraying mechanism (5) and a filtering mechanism (6) are further arranged in the ventilation pipe (1). The lifting mechanism (4) comprises a mounting plate (41) fixedly connected to the side wall of the inner pipe (2) and a connecting plate (42) fixedly connected to the side wall of the ventilation pipe (1), a first driving motor (43) is fixedly mounted on the mounting plate (41), the output end of the first driving motor (43) is fixedly connected with a reciprocating screw rod (44), and the reciprocating screw rod (44) penetrates through and is in threaded connection with the connecting plate (42); the mine air purification device can purify and discharge air containing metal dust at different heights in a mine, and the air purification effect is improved.

The application belongs to the technical field of slag slurry pumps, and discloses a submerged slag slurry pump which comprises a support, a pump body, an impeller, a discharge pipe, a driving structure and a flow guide structure. The support is internally hollow. The bottom of the pump body is provided with an inlet, and the side of the pump body is provided with a discharge outlet. The impeller is arranged in the interior of the pump body. The discharge pipe is arranged on the side of the pump body and is in communication with the discharge outlet. The driving structure is arranged on the top of the support and is used for driving the impeller to rotate. The flow guide structure comprises a follow-up shaft arranged at the bottom of the impeller and flow guide blades arranged on the follow-up shaft. The follow-up shaft extends to the outside of the pump body through the inlet. The flow guide blades are located outside the pump body. The follow-up shaft can drive the flow guide blades to rotate along with the impeller, so that the slag slurry moves towards the direction where the inlet is located under the action of the flow guide blades, thereby improving the feeding efficiency of the pump body and the pumping efficiency of the submerged slag slurry pump on the slag slurry.

The utility model relates to the technical field of landfill, and discloses a double-effect condenser pipe for a gas extraction well of a landfill, and a condenser pipe assembly comprises a condenser pipe upper pipe, a condenser pipe middle pipe, a condenser pipe rear pipe and a condenser pipe lower pipe; the device is used for landfill gas water vapor condensation and automatic guide and drainage of condensate water. The condensation pipe upper pipe is connected with an original gas outlet of a gas extraction well pipe on a landfill pile body, and the condensation pipe upper pipe extends upwards to be connected into the condensation pipe middle pipe; the condenser pipe middle pipe extends downwards to be connected into the condenser pipe rear pipe; the connecting part of the middle condensing pipe and the rear condensing pipe is positioned at the lowest point of the middle condensing pipe and the condensing pipe, a tee joint for connecting the middle condensing pipe, the rear condensing pipe and the lower condensing pipe is arranged at the connecting part, and the lower condensing pipe is designed to extend downwards; the double condensation design and the automatic drainage function are matched with each other, water vapor in landfill gas is treated from two stages, condensate water is drained in time, condensation and accumulation of the water vapor in a pipeline are effectively reduced, the pipeline blockage risk is greatly reduced, and it is guaranteed that the landfill gas is conveyed smoothly.

A new type of single-casing slurry pump includes a shaft frame with a rotating shaft rotatably mounted inside. A flange is fixedly connected to one end of the shaft frame, and a protective sleeve is fitted onto the flange. Bolts are installed between the protective sleeve and the flange. Four impellers are fixedly mounted at the head of the rotating shaft, with the impeller inlet extending forward. The outer diameter of the back blade is smaller than the diameter of the cover plate. The impellers are located inside the protective sleeve, and a guide block is provided on the end face of the protective sleeve, slightly lower than the height of the cover plate, suitable for waterless sealing scenarios. The bearing assembly uses a mature lubrication structure, prioritizing synthetic grease to ensure bearing stability. The waterless sealing design solves the leakage problem of traditional seals, extending the maintenance cycle by more than 30%. The four impellers and optimized guide blocks improve pump efficiency by 5%-8%, and offer superior cavitation resistance compared to similar products. The back blades and the guide block on the protective sleeve reduce localized wear, extending the life of flow components by more than 20%, improving overall practicality.

This utility model provides a tunnel silt removal device, including a base plate and a removal mechanism disposed on the outer side of the end of the base plate. The removal mechanism includes a hydrocyclone body, which is installed on the upper surface of the base plate. A connecting plate is fixedly connected to the outer side of one end of the base plate. In use, the device can be quickly moved to a designated position by wheels, improving work efficiency and reducing the time and physical exertion of manual handling. Users can use the hydrocyclone body to remove silt from specific areas, ensuring the accuracy of silt removal and avoiding resource waste. After starting the first motor, the rotating arm rotates, realizing automated operation, reducing manual intervention, improving efficiency, and reducing the difficulty of operation.

This application belongs to the technical field of air extraction equipment, specifically an electric air extraction pump, including a main unit and an impeller. The end of the main unit has an air inlet structure that connects to the air inlet channel. The impeller includes a shaft and multiple blades arranged around the shaft. The root end face of each blade has a recessed portion extending from the air inlet side of the impeller to the air outlet side, so that a recessed area is formed around the periphery of the shaft on the air inlet side of the impeller. By setting the recessed portion at the root of the blade, the recessed portions of each blade are combined to form an annular recessed area on the air inlet side of the impeller near the shaft. Therefore, when the impeller rotates, the air inlet space can be expanded, the air volume can be increased, and the extraction efficiency can be improved. By setting the recessed portion at the root of the blade near the shaft, the flow space can be expanded directly in the initial area where the airflow enters, avoiding the obstruction of the airflow by the blade root, allowing the air to flow more smoothly to the center of the impeller and reducing flow resistance.