52results about How to "Extend the spray time" patented technology

The invention provides an automatic passive fire protection spraying valve, which belongs to the field of automatic fire protection control equipment and is characterized in that a valve body is internally provided with a cylindrical water outlet. A membrane type piston is arranged on the upper end of the water outlet. A return spring is arranged in the middle upper part of an internal sleeve. The upper part of the resetting spring is supported against the inner upper part of a valve cover. The external top part of an external sleeve of a valve core is provided with a compression bar which iscovered by a pressure spring. The compression bar passes through a round hole at the top of the internal sleeve and is connected with an adjusting nut on a hot gathering cover. Due to the delayed action of the pressure spring, a defect that a valve is immediately closed when a memory alloy contracts is avoided and the spraying time is delayed.

The invention discloses a long air spark gap ignition mechanism. The long air spark gap ignition mechanism is characterized in that a high-energy plasma ejection device is mounted on one electrode column of the spark gap. The plasma ejection device comprises a high-voltage electrode, an intermediate-voltage electrode and a low-voltage electrode, wherein the intermediate-voltage electrode divides a flashover gap channel into a short gap channel and a long gap channel; and the intermediate-voltage electrode and the low-voltage electrode are connected an inductor therebetween to serve as a voltage division unit and an energy storage unit of a discharge circuit. The inductor is used as the voltage division unit at the initial discharge period, and then is used as the energy storage unit to achieve follow current of long gap channel arc after the energy of a discharge capacitor is released completely. The plasma ejection device can stably eject a large amount of plasma under lower discharge voltage multiple times, and the plasma ejection speed exceeds sound velocity by multiple times. The plasma ejection device can be used repeatedly with substantially no performance change after repeated ejection, and can reliably ignite and breakdown the long air spark gap.

The invention provides an optimizing control method of an electrostatic spraying array system, which belong to the technical field of electrostatic spraying. The electrostatic spraying array system comprises at least two electrostatic spraying units and is characterized in that each electrostatic spraying unit comprises a charge generating or injecting switch (6) which is independent or shared by other electrostatic spraying units and a liquid flow rate control device or a liquid conveying switch (7) which is independent or shared by the other electrostatic spraying units; the electrostatic spraying array system also comprises an automatic control device (4) which is connected with the charge generating or injecting switch (6) and the liquid flow rate control device or the liquid conveying switch (7); and the automatic control device (4) controls the switching modes of spray heads, namely the spray switching state, time and period of each spray head through one of the following modes or combination of the several modes: controlling charge generating or injecting channels, or liquid flow rates or liquid conveying on-off states. The invention has the characteristics of high practicability, uniform spray and capability of being massively used inindustrial production.

A vertical internal coating machine is taught, which may be used with bodies such as cans (2 piece, 3 piece, draw, redraw,) and including cylinders, containers and any similar body. In the machine cans or similar bodies are vertical in the machine's star wheel rather than horizontal, and the bodies are sprayed with the star wheel in continuous motion without stopping and starting. The machine teaches that a plurality of spray guns may be provided for each pocket of the star wheel. By means of the machine an improved line layout is devised which may eliminate the need to raise the bodies immediately prior to a necker by allowing the vertical can internal coating machine and internal bake over to be disposed on any level of the facility, upper, lower, mezzanine, etc. In green aspects, the machine may use negative pressure cabinets / hoods and positive pressure tunnels to entrain volatile organic chemicals emitted by the spray guns and coated bodies and may send these VOCs to a VOC desctruction device, such as an oven.

The invention provides a building outer wall spraying robot and a control method thereof, and relates to the technical field of building robots. The building outer wall spraying robot comprises a machine frame, a material storage box and a spraying machine, wherein the material storage box and the spraying machine are arranged on the machine frame, a spraying gun of the spraying machine is provided with a rotating mechanism capable of changing a spraying direction, and the spraying gun is fixed on a horizontal moving device capable of sliding in the horizontal direction of the machine frame; and the machine frame is provided with a lifting mechanism for enabling the machine frame to move in the direction of a plumb bob, and a stability maintaining mechanism for adjusting the movement stability of the machine frame, an outer wall recognition device for identifying a spraying region is further arranged on the machine frame, and the outer wall recognition device, the rotating mechanism, the horizontal moving device and the lifting mechanism are electrically connected to a controller. According to the robot and the method, the problems that in the prior art, manual building outer wallspraying is dangerous, the efficiency is low, and the spraying quality is not stable are solved.

A passive containment heat removal system, control method thereof and pressurized water reactor; the passive containment heat removal system comprises an outer containment (2), an inner containment (1), an air duct (200) defined between the inner containment (1) and the outer containment (2) having an air inlet (4) and an air outlet (5), a spraying assembly (10) disposed outside the inner containment (1), a built-in heat exchanger (9) disposed in the inner containment (1), an air cooling channel (171) located outside the outer containment (2) having an air inlet (18) and air outlet (21) of an air cooling channel (171), and an external air cooler (12) disposed in the air cooling channel (171); the inlet of the external air cooler (12) is connected to the outlet of the built-in heat exchanger (9) via a first communication pipe (13), and the outlet of the external air cooler (12) is connected to the inlet of the built-in heat exchanger (9) via a second communication pipe (14).

The invention discloses a fire extinguishing device of an energy storage box. The energy storage box comprises at least one battery box, hollow supporting columns used for supporting the battery boxesand a fire extinguishing mechanism used for extinguishing fire of the battery boxes; a ventilation opening is formed in the back face of each battery box, and the supporting columns communicate withthe battery boxes; and the fire extinguishing mechanism comprises a fire extinguishing main pipe, a fire extinguisher and an electromagnetic valve, the output end of the fire extinguisher communicateswith the fire extinguishing main pipe through the electromagnetic valve, the fire extinguishing main pipe communicates with one ends of the supporting columns, the fire extinguisher forms a fire extinguishing channel sequentially through the fire extinguishing main pipe, the supporting columns and the ventilation openings, first fire extinguishing holes are formed in the supporting columns, second fire extinguishing holes communicating with the first fire extinguishing holes are formed in the battery boxes, and the fire extinguisher forms a fire extinguishing channel sequentially through thefire extinguishing main pipe, the first fire extinguishing holes, the second fire extinguishing holes and the ventilation openings. The occupied space of the energy storage box is saved, and meanwhile, the fire extinguishing efficiency and the fire extinguishing quality are improved.

An oxygenating and water spraying live fish transport case system of the present invention comprises a live fish transport case and an oxygenation system. In the live fish transport case, a case body (1) is covered by a case cover (2), a clapboard (6) is connected with the case body (1), and ice (7) is arranged on a lower supporting plate (13). A storage battery (9) and a switch (14) are arranged on an upper supporting plate (8), a water pipe (3) penetrates the clapboard (6) to be connected with a submersible pump (12), and the submersible pump (12) is in the water (5) under the lower supporting plate (13). A pollution absorption pad (10) is lain flatly at the bottom of the case body (1), and a filter net (11) is in a hole at the lower part of the clapboard (6) and in the water (5). In the oxygenation system, a liquid oxygen tank (26) is connected with an oxygenating cover plate (24) via an oxygen pipe (23) and an inflation / deflation valve (25). The oxygenating and water spraying live fish transport case system of the present invention is used to oxygenate the live fish transport case, and increases the oxygen in the water by spraying water, thereby improving a live fish transport environment.

The invention discloses a weft insertion device for an air-jet loom and an automatic adjusting method of the weft insertion device. The weft insertion device comprises a yarn stopping needle, an auxiliary main nozzle, a swing main nozzle, a weft detector, a main air bag, an auxiliary air bag, an electromagnetic valve control device, a main control computer, a display input device, an encoder, auxiliary nozzles and auxiliary spraying electromagnetic valves, wherein the auxiliary nozzles form an auxiliary nozzle group; the main control computer is electrically connected with the electromagneticvalve control device, the display input device, the encoder and the weft detector; the electromagnetic valve control device is in electrical signal connection with the yarn stopping needle, a first electromagnetic valve, a second electromagnetic valve and the auxiliary spraying electromagnetic valves; the auxiliary main nozzle is connected with the main air bag through the first electromagnetic valve; the swing main nozzle is connected with the main air bag through the second electromagnetic valve; the auxiliary nozzles are connected with the auxiliary air bag through the auxiliary spraying electromagnetic valves respectively. The jet starting time and the jet ending time of the auxiliary nozzles can be dynamically adjusted, the jet compressed air is minimized, weft insertion is stably conducted, and the labor amount of an operator is reduced.

The invention relates to an efficient hydrogen chloride tail gas absorption device and belongs to the technical field of tail gas treatment. The device comprises a first absorption tank, a second absorption tank and a water pumping mechanism, a spraying water outlet mechanism is arranged in the first absorption tank, a hollow shaft is rotatably connected to the bottom of the first absorption tank, and an exhaust pipe is arranged at the top; a driving mechanism is arranged at the lower end of the hollow shaft, the upper end extends into the first absorption tank and is connected with a rotating rod, a tail gas exhaust mechanism is arranged on the hollow shaft, and the upper end of the rotating rod is connected with an exhaust mechanism; the bottom of the second absorption tank is rotationally connected with a lower hollow rod, the lower hollow rod and the hollow shaft are in transmission through a transmission mechanism, the upper end of the lower hollow rod extends into the second absorption tank and is fixedly provided with an upper hollow rod, the outer wall of the upper hollow rod is provided with an air outlet mechanism, and the upper end of the upper hollow rod is rotationally connected with the tail end of the exhaust pipe; a pollution discharge mechanism is arranged on the outer wall of the lower hollow rod; and the water pumping mechanism is respectively connected with the spraying water outlet mechanism and the second absorption tank. The device can fully absorb the hydrogen chloride tail gas.

A low pressure fogging device includes a fogging device body having a hose coupling tube formed unitarily with the lower side thereof, a screw portion formed on the upper side thereof, and a fluid flow-inducing member seating plate formed on top of the screw portion; a fluid flow-inducing member having induction wings seated on top of the fluid flow-inducing member seating plate; a nozzle body having a fitting hole open downwardly therefrom to allow the fluid flow-inducing member seating plate and the fluid flow-inducing member to be fitted thereto; and a push-up nut having a pressuring ring formed at the center thereof to be locked onto a locking projection formed from an outer lower end periphery of the nozzle body and a screw groove formed at the inner periphery thereof to be fastened to a screw portion formed on the fogging device body.

The invention discloses a highly-efficient building construction dedusting device. The highly-efficient building construction dedusting device comprises a shell, wherein the bottom part of the shell is provided with bilaterally-symmetrical supporting rods; the right end of the interior of the shell is provided with an air inlet; the interior of the air inlet of the shell is provided with an air suction fan; the central part of the shell is provided with a horizontal sleeve drum; spray holes are uniformly arranged on the outer side wall of the horizontal sleeve drum; flow guide plates are uniformly arranged at the top part of the shell at intervals; each flow guide plate is obliquely arranged to left bottom; ultraviolet sterilizing lamps are fixedly arranged on the top wall of the shell located between the flow guide plates; the left end of the shell is provided with an air outlet; the bottom part of the shell is obliquely arranged to right bottom to form a water collection groove; theleft side of the bottom part of the shell is provided with a water storage chamber; and the interior of the water storage chamber is provided with a water pump which communicates with the left end ofthe horizontal sleeve drum through a water pipe. The mobile building construction dedusting device provided by the invention has ingenious structure and reasonable arrangement, realizes highly-efficiency dedusting and sterilization, saves water and facilitates pollution discharge.

The invention provides a silicon wafer de-gluing machine which comprises a primary filter box which is communicated with a first tank and used for recovering waste water discharged from the tank; a secondary filter box which is communicated with the primary filter box and used for filtering the water discharged from the primary filter box; a tertiary filter box which is communicated with the secondary filter tank and a third tank and used for filtering the water discharged from the secondary filter box and recovering the waste water discharged from the third tank; a water storage tank which iscommunicated with the tertiary filter box and the first tank and used for storing water discharged from the tertiary filter tertiary and supplying spray water to the first tank; a heater which is isarranged between the water storage tank and the first tank and used for heating water discharged from the water storage tank; a pure water source which replenishes the water storage tank with the spray water; and a controller which detects existence of silicon wafers sprayed in the spray tank by position sensors arranged in the first tank, the second tank and the third tank and discharges the spray water from the water storage tank and / or the pure water source. The invention also provides a control method of the silicon wafer de-gluing machine. The surface quality of the silicon wafer can be improved, the spray water can be recycled, the production cost can be reduced and the product quality can be improved.

The invention relates to a preparation method of an anti-corrosion self-adhesive polymer modified asphalt waterproof coiled material. The preparation method comprises the following steps: S1, preparing jelly; S2, preparing a modified asphalt layer; S3, starting a spraying device by the control unit to spray the jelly obtained in the step S1 on the modified asphalt layer in the step S2 to form a spraying layer, and when the spraying layer is sprayed to a preset thickness, obtaining an adhesive layer; and S4, applying a PET film to the adhesive layer in the step S3, and flattening, through a roller, and coiling the adhesive layer, and packaging the adhesive layer in a sealed mode. The control unit compares the actual spraying layer increasing thickness with the preset spraying layer increasing thickness, the spraying frequency of the spraying assembly and the rotating speed of the driving assembly are adjusted according to the comparison result, the spraying process is precisely controlled through the control unit, and therefore the increasing thickness of the spraying layer meets the preset standard after spraying every time, while the spraying efficiency is improved, the waste of materials can be effectively avoided, and the quality of the waterproof coiled material is further ensured.

The invention discloses a highway pavement pressing device and method using building demolition crushed aggregates for construction, the highway pavement pressing device and method using building demolition crushed aggregates for construction comprise a pressing vehicle, the pressing vehicle comprises a crushed aggregate recycling mechanism, a processing mechanism and a dust falling mechanism, the crushed aggregate recycling mechanism is located at the front end of the pressing vehicle, and the processing mechanism is located at the front end of the pressing vehicle; the machining mechanism is located in the pressing vehicle, the dust falling mechanisms are located at the front end and the rear end of the pressing vehicle, the crushed material recycling mechanism comprises a stone crushing assembly, a conveying assembly and a hammering assembly, and the hammering assembly is located at the front end of the crushed material recycling mechanism and is lower than the stone crushing assembly. The stone crushing assembly is located at the front end of the conveying assembly and is in a roller shape, the conveying assembly is located in the pressing machine, and the processing mechanism comprises a processing cavity, a processing cavity temperature regulation and control system, a stirring machine and a stirring machine regulation and control system.

The invention discloses a manufacturing method of a liquid injector head. The liquid injector head comprises a device body, an injection device arranged in the device body and a switching device arranged in the device body. The switching device comprises a first working cavity formed in the device body. A slide plate is connected into the first working cavity in a sliding fit mode. First springs are fixedly arranged on the right end surface of the slide plate and symmetric up and down, and the right ends of the first springs are fixedly connected with the right side end surface of the first working cavity. The right side end wall of the first working cavity communicates with a connecting rod cavity. A first connecting rod extending rightwards is fixedly arranged on the right end surface ofthe slide plate. A slide block connected with the connecting rod cavity in a sliding fit mode is fixedly arranged at the right end of the first connecting rod. An internal connecting groove with a rightward opening is formed in the slide block. First fixing shafts are fixedly arranged on the front and rear side end walls of the internal connecting groove correspondingly. According to the device,a plurality of water tanks are integrated, an increase of the water storage amount can prolong the injection time of a water gun, liquid in different colors can be injected, and the experience feelingof a player is improved.

The invention discloses a flue dust desulfurizing device for a thermal power generation plant, and relates to the technical field of thermal power generation. The flue dust desulfurizing device comprises a base, wherein the left side of the upper surface of the base is fixedly connected with a stirring mechanism; the middle part of the upper surface of the base is fixedly connected with a coolingand spraying mechanism; the cooling and spraying mechanism is positioned at the right side of the stirring mechanism; the right side of the upper surface of the base is fixedly connected with a discharge mechanism; the discharge mechanism is positioned at the right side of the cooling and spraying mechanism. The flue dust desulfurizing device for the thermal power generation plant has the advantages that by arranging the stirring mechanism, under the function of an air blower, a desulfurizing catalyst is fully stirred and mixed with a sodium carbonate solution and air, the stirred desulfurizing solution is completely activated, and the sulfur-containing flue dust is completely desulfurized; by arranging a cooling pipeline, the temperature of the flue dust before desulfurizing is reduced, and the flue dust is more fully desulfurized; by arranging a filtering box, the desulfurized gas is fully filtered, the desulfurized flue gas is cleaner, and the environment is effectively protected.

The invention relates to the field of hydraulic engineering construction, in particular to a construction method of a lock chamber underground continuous wall enclosed high pressure jet grouting pile of a lock chamber. The construction method is characterized by comprising the following steps: step 1, pile lofting; step 2, drilling machine positioning; step 3, grout preparing; step 4, drilling and reaming; step 5, jet grouting accelerating; step 6, drilling machine shifting; and step 7, washing. The construction method has the beneficial effects that the underground continuous wall enclosure structure is high in stability, the equipment damage rate is low, the construction period is short, and the cost is low.

The invention discloses a device for preparing shower water for a water closet having an under-shower. The device has a line arrangement (2), which possesses an inlet (3) connectable to a supply line and an outlet (4) connectable to a shower arm (5). A heating element (6) serves for the provision of warm water. An energy store (7, 8) is provided, with which the power range for the provision of shower water can be extended. The heating element (6) for the provision of warm water is, in particular, a continuous-flow heater. The energy store (7, 8) is, in particular, a thermal, electrical, electrochemical or chemical energy store. During the shower process, the energy store is available as an additional energy source for the preparation of shower water. The invention also discloses a method for operating the device for preparing shower water for a water closet having an under-shower.

The invention discloses a metal smelting tail gas recovery treatment system and a treatment method thereof, and relates to the field of smelting tail gas treatment. The metal smelting tail gas recovery treatment system comprises a spraying box, a gas mixing cylinder is integrally formed on one side of the bottom of the spraying box, a plurality of branch insertion pipes are connected to an annular pipe at the bottom of the gas mixing cylinder in a branching mode and obliquely penetrate to the bottom of the gas mixing cylinder, and air blowing heads are arranged at the ends of the branch insertion pipes; the system has the beneficial effects that an alkaline absorbent at the bottom of the gas mixing cylinder is pumped through a water pump and supplied to spray heads arranged at the upper ends of a first channel, a second channel and a third channel for spraying, so that the alkaline absorbent and tail gas are subjected to contact reaction, an S-shaped channel formed by the first channel, the second channel and the third channel is used for circulation, the flow distance of the tail gas in the gas mixing cylinder is improved, the spraying time is prolonged, and the occupied area required by equipment is greatly reduced while the sulfur dioxide absorption effect is ensured.

The invention relates to the technical field of waste treatment, and discloses a multi-stage dust fall and noise reduction environment-friendly multi-mode building solid waste regeneration treatment system comprising a treatment box. Holes are formed in the upper side and the lower side of the front face of the treatment box correspondingly, and the upper side and the lower side of the front face of the treatment box are fixedly connected with an input box and an output box correspondingly. The top face of the right side of the input box is fixedly connected with a fixed plate. The fixed plate is sleeved with sliding plates A, and each sliding plate A is connected with a spraying plate, through the arrangement of the spraying plates, in the process that the building solid waste is conveyed into the treatment box, the two spraying plates continuously conduct spraying in a following mode from front to back through high-speed rotation of a transmission shaft of a jaw crusher, the spraying range is guaranteed, and meanwhile, the spraying time is prolonged. The requirement for the water amount is met, the noise problem generated by high-pressure water discharge and the dust raising problem caused by the fact that water flow strikes the building solid waste are also avoided, and furthermore, the jaw crusher is sealed in the treatment box for use so that noise transmission can also be reduced.

A cleaning machine for casting products comprises a conveying device, a cleaning device, a filtering device and a hydraulic system. The conveying device comprises a tank body and a net belt conveyor, the net belt conveyor is arranged in the tank body, and a through opening is formed in the bottom of the tank body. The cleaning device comprises a shell and a spraying system, the spraying system is arranged in the shell, and the shell is installed on the tank body. The filtering device comprises a liquid storage tank, a chain type conveyor, a grid filtering device, a filtering net and a filtering net placement frame. The grid filtering device and the filtering net can carry out dual filtering, and the spraying system can carry out cleaning and oil-impregnated treatment on casting products.

The invention discloses a water spraying method and device for heat dissipation of a condenser and a radiator of a vehicle. The method comprises the steps: obtaining a temperature before heat dissipation and defining the temperature as an initial temperature; when it is detected that the initial temperature is higher than the preset temperature, opening an electromagnetic valve for first preset time; obtaining a temperature after heat dissipation, and defining the temperature as a comparison temperature; calculating a temperature difference value between the initial temperature and the comparison temperature, and judging whether the temperature difference value is smaller than a preset difference value or not; and if yes, prolonging the duration of opening the electromagnetic valve to second preset time, and obtaining the temperature after heat dissipation again. The water spraying device is controlled to assist in accelerating heat dissipation of cooling fins by detecting the temperature, the temperature difference is further calculated to reflect the working state of a heat dissipation system, a user can conveniently master the heat dissipation condition of a vehicle in time, and safe driving is achieved.

The invention discloses a temperature-control automatic on-off type water fire extinguishing control valve which comprises a connecting end cover, a sleeve, a middle connecting section, a fixing cap, a magnetic ring sleeve, a telescopic rod, a one-way memory alloy telescopic spring, a compression spring and a movable column. In the valve, the one-way memory alloy telescopic spring is adopted and can only stretch out without drawing back at high temperature and draw back under the support of the compression spring, in the working process, the one-way memory alloy telescopic spring supports the telescopic rod so as to control the valve to be switched on, the one-way memory alloy telescopic spring is only responsible for supporting the telescopic rod but not drawing back and draws back mainly through the support of the compression spring, and therefore the switch-on time of the valve is effectively prolonged. The one-way memory alloy telescopic spring is improved.

The invention provides an automatic passive fire protection spraying valve, which belongs to the field of automatic fire protection control equipment and is characterized in that a valve body is internally provided with a cylindrical water outlet. A membrane type piston is arranged on the upper end of the water outlet. A return spring is arranged in the middle upper part of an internal sleeve. The upper part of the resetting spring is supported against the inner upper part of a valve cover. The external top part of an external sleeve of a valve core is provided with a compression bar which iscovered by a pressure spring. The compression bar passes through a round hole at the top of the internal sleeve and is connected with an adjusting nut on a hot gathering cover. Due to the delayed action of the pressure spring, a defect that a valve is immediately closed when a memory alloy contracts is avoided and the spraying time is delayed.

The invention discloses a long air spark gap ignition mechanism. The long air spark gap ignition mechanism is characterized in that a high-energy plasma ejection device is mounted on one electrode column of the spark gap. The plasma ejection device comprises a high-voltage electrode, an intermediate-voltage electrode and a low-voltage electrode, wherein the intermediate-voltage electrode divides a flashover gap channel into a short gap channel and a long gap channel; and the intermediate-voltage electrode and the low-voltage electrode are connected an inductor therebetween to serve as a voltage division unit and an energy storage unit of a discharge circuit. The inductor is used as the voltage division unit at the initial discharge period, and then is used as the energy storage unit to achieve follow current of long gap channel arc after the energy of a discharge capacitor is released completely. The plasma ejection device can stably eject a large amount of plasma under lower discharge voltage multiple times, and the plasma ejection speed exceeds sound velocity by multiple times. The plasma ejection device can be used repeatedly with substantially no performance change after repeated ejection, and can reliably ignite and breakdown the long air spark gap.

The invention discloses a fire extinguisher nozzle structure. The fire extinguisher nozzle structure comprises a nozzle, and further comprises a pipe body arranged in the nozzle, wherein the pipe body is provided with three layers of pipe walls; the adjacent pipe walls are connected through guide pieces in the axial direction of the pipe body; the aperture of the pipe wall on the innermost layer of the pipe body is decreased from an inlet end to an outlet end of a fire extinguishing agent; and the aperture of the pipe wall on the second layer of the pipe body is increased from the inlet end to the outlet end of fire extinguishing agent. The invention aims to provide the fire extinguisher nozzle structure for solving the problem of incapability of injection at a larger distance in prolonging of the fire extinguisher injection time and widening of the fire extinguishing range in a traditional fire extinguisher nozzle.

The invention discloses a planting method of selenium-enriched wasabi and relates to the technical field of selenium-enriched planting. The planting method includes the steps of firstly, selecting soil with heavy metal being lower than an environment background value or treating heavy metal in soil to allow the heave metal to be lower than the environment background value for standby; secondly, sowing wasabi seeds into the soil provided in the first step, allowing the wasabi seeds to germinate, and transplanting wasabi seedlings into a greenhouse after the wasabi seedlings grow to 10-12cm in autumn, wherein the daily sunshine duration of the growth environment of the wasabi is controlled not to exceed 2 hours, growth temperature is controlled to be 10-24 DEG C, and the soil in the greenhouse is the soil provided in the first step; thirdly, in a period after the wasabi grows for 2-3 months and one month before the harvest period of the wasabi, watering the wasabi with selenium-enriched water with the mass concentration being 100-600mg / Kg twice each month; fourthly, drying harvested wasabi with cold air to obtain the selenium-enriched wasabi.

The invention relates to the technical field of spraying equipment, and discloses an electric arc spray gun for coating spraying. The spray gun comprises a spray gun head, and a contact tube is fixedly arranged on one side, close to a coating spraying side, of the spray gun head. According to the electric arc spray gun for coating spraying, through cooperation of a movable air pipe and a guide wheel, after wires make contact, the guide wheel stops rotating, then the movable air pipe moves towards one side of an air inlet pipe, and an air inlet hole enters the movable air pipe, so that the movable air pipe is in communication with the interior of the air inlet pipe; in the moving process, the wires reach a molten state, and air flow is introduced to blow out the molten coating after the wires are molten, so that the surface temperature of the wire rises quickly, the heat loss in the contact tube is reduced, the spraying time is shortened, and the spraying efficiency is improved; and meanwhile, the wires are connected with the guide wheels in parallel, so that feeding and melting of the wires are carried out alternately to form prepared materials, excessive wires in the contact tube are avoided, and material preparation in the contact tube is smooth.