763 results about "Shut down valve" patented technology

Systems and methods which provide control of lubricant delivery with respect to chainsaws using a lubricant flow shutoff valve controlled in correspondence to an operational state of the chainsaw. A chainsaw lubricant delivery control system includes a lubricant flow shutoff valve and a chainsaw operation-based valve controller operable cooperatively to provide control of lubricant delivery to the cutting chain and guide bar assembly of a chainsaw. The chainsaw operation-based valve controller is coupled to an operationally active element of the chainsaw wherein the chainsaw operation-based valve controller may control the lubricant flow shutoff valve between an open position and a closed position responsive to detecting a particular state of the operationally active element corresponding to an operational state of the chainsaw.

The utility model discloses a high-pressure inflation pipeline structure wound on an IV-type hydrogen storage cylinder inner container, which comprises a nitrogen cylinder, the output end of the nitrogen cylinder is sequentially connected with a high-pressure reducing valve, a one-way valve, a low-pressure reducing valve, a pressure release valve, a pressure gauge and a stop valve through a high-pressure connecting pipe, and the stop valve is connected with the IV-type hydrogen storage cylinder inner container. The high-pressure inflation pipeline is provided with the high-pressure reducing valve, the one-way valve, the low-pressure reducing valve, the pressure release valve, the pressure gauge and the stop valve, so that the functions of monitoring, adjusting and pressure release of the internal pressure during winding of the IV-type hydrogen storage cylinder liner can be realized, and the problem that the IV-type hydrogen storage cylinder liner is expanded and broken due to overlarge pressure or insufficient support due to oversmall pressure during winding and inflation is avoided; and the normal use and the use safety of the IV-type hydrogen storage bottle liner winding are ensured.

The invention discloses a hydraulic speed regulation control system of a feed pump turbine valve, which comprises a regulating valve control unit, and the regulating valve control unit comprises a regulating valve hydraulic control block and a regulating valve hydraulic servo-motor. A servo valve, a filter, a hydraulic control one-way valve, a differential pressure type plug-in loading and unloading valve, an upper plug-in stop valve, a lower plug-in stop valve, a quick-closing electromagnetic valve, a first pressure oil channel, a first oil discharge channel and a safety oil channel are fixed in the adjusting valve hydraulic control block. The safety oil duct is connected with the first pressure oil duct and the differential pressure type plug-in loading and unloading valve. The quick-closing electromagnetic valve is connected in parallel between the safe oil duct and the oil discharge channel I; an oil inlet of the servo valve is communicated with the filter, a control oil port is connected with the differential pressure type plug-in loading valve through the hydraulic control one-way valve, and the differential pressure type plug-in loading valve is connected with the lower plug-in stop valve; and the regulating valve hydraulic servo-motor is respectively connected with the upper cartridge stop valve and the lower cartridge stop valve. According to the system, the servo valve and the filter element can be replaced on line, and the technical problem that the servo valve and the filter element cannot be replaced on line in an existing regulating valve speed regulating system is solved.

A toilet seat arrangement includes a toilet seat that is installed above a toilet bowl. A bidet nozzle is installed on the toilet seat and ejects water into a space above the toilet bowl such that the water falls into the toilet bowl. A water level sensor is installed on the toilet seat and detects a level of water in the toilet bowl. The water level sensor transmits a signal indicative of the level of water in the toilet bowl. A shutoff valve allows water to flow to a toilet tank fill valve when the shutoff valve is in an open position, and prevents water from flowing to the toilet tank fill valve when the shutoff valve is in a closed position. An electronic processor controls whether the shutoff valve is in the open position or the closed position dependent upon the signal from the water level sensor.

The invention relates to the technical field of air conditioning systems, in particular to a method for air conditioner refrigerant replacement, and aims to solve the problem of how to replace combustible refrigerants under the condition that a pipeline is not disassembled in an existing non-combustible refrigerant air conditioning system. In order to achieve the purpose, the method comprises the following steps that S11, the amount of refrigerants needed by a to-be-replaced air conditioning system is detected; s12, the quantity of refrigerants capable of being recycled is judged according to the outdoor unit; s13, whether the refrigerant can be directly recycled or not is judged according to the relation between the refrigerant recycling amount and the required refrigerant amount; if yes, entering the step S14; and S14, the refrigerant of the air conditioning system is directly replaced. In the process of replacing the refrigerant or after the refrigerant is replaced, if leakage occurs in the indoor unit, the refrigerant can be prevented from leaking through recycling of the outdoor unit, closing of the block valve or closing of the newly-added valve box or the stop valve, the combustible refrigerant can be prevented from continuously leaking, and it is guaranteed that safety accidents such as fire disasters or explosions cannot occur.

The utility model discloses a leak detection type stop valve, which belongs to the technical field of valves and comprises a valve body, a valve cover is detachably mounted at the top of the valve body, a valve rod is rotatably mounted in the valve cover, and a valve core is fixedly mounted at the bottom end of the valve rod; a vertically-separated separation section is arranged in the valve body, and a valve port is formed in the separation section in a penetrating mode. A leakage detection valve sleeve is assembled at the bottom of the valve body in a sealed mode through threads, a leakage detection valve pipe is sleeved with the leakage detection valve sleeve, a sealing cover is fixed to the top of the leakage detection valve pipe, a plurality of flowing grooves are formed in the side wall of the top end of the leakage detection valve pipe, and a leakage detection opening is formed in the bottom end of the leakage detection valve pipe. A sliding seat is fixed on the side wall of the bottom section of the leak detection valve tube, the sliding seat is slidably mounted on a guide shaft fixed in the leak detection valve sleeve, and a spring for pushing the sliding seat to move downwards is mounted on the guide shaft in a sleeving manner. According to the leak detection type stop valve, the leak detection valve sleeve, the leak detection valve pipe and other assemblies are arranged, the sealing performance of the valve element in the closed state can be overhauled, the whole valve does not need to be disassembled, and the leak detection type stop valve is more convenient to overhaul.

The invention discloses a low-temperature safety valve leakage detection device based on electrical capacitance tomography, which comprises a liquid nitrogen storage container, a test container, a low-temperature stop valve, a detected low-temperature safety valve, a constant-temperature water bath device, a flow meter, a water tank, a leakage detection pipeline, a capacitance measurement system and a data acquisition and software system, the capacitance measuring system comprises a plurality of groups of copper electrode plates and a processing module, each group of copper electrode plates comprises two copper electrode plates arranged on two opposite side parts of the water tank, and the copper electrode plates are used for capturing bubbles formed by the low-temperature gas in the cavity and acquiring capacitance signals; and the copper electrode plate is electrically connected with the data acquisition and software system through the lead electrode plate connector and the shielding coaxial cable. Insulation supports are arranged between the water tank and the copper electrode plates, the interior of the water tank is divided into a plurality of cavities, and communication gaps are formed between the adjacent cavities. The invention further discloses a low-temperature safety valve leakage detection method based on electrical capacitance tomography. According to the method, the accuracy and comprehensiveness of calculating the leakage rate of the low-temperature gas are improved.

A controller is configured to control an internal combustion engine mounted on a vehicle. The controller includes processing circuitry. The processing circuitry outputs a valve closing signal to a shut-off valve, and executes, when a stopping operation of the internal combustion engine is performed, a determination process of determining whether the shut-off valve is stuck open based on a decrease amount of a passage fuel pressure. The controller does not execute the determination process when at least one of a condition that a vehicle speed is higher than a first determination speed and a condition that an engine rotation speed is higher than or equal to a second determination speed is met.

The utility model discloses a frost valve with a temperature control device, which comprises a valve body, a temperature sensing stop valve is arranged at the top of the valve body, a drainage component is arranged at the bottom of the valve body, screws are arranged at four corners of the top of the valve body, a mounting seat is arranged in the temperature sensing stop valve, a diaphragm body is arranged at the top of the mounting seat, and a temperature control device is arranged on the diaphragm body. A first valve rod is arranged in the temperature sensing stop valve, a first spring is arranged in the first valve rod, the surface of the first valve rod is sleeved with a first memory alloy spring, and the bottom of the first valve rod is fixedly connected with a sealing gasket. According to the anti-freezing valve, the phenomenon that opening and closing of the valve body cannot be controlled according to the temperature of water flow in the prior art is changed, meanwhile, the phenomenon that electric heating or combustion heating fails without electricity in the prior art is avoided, and the first valve rod, the first memory alloy spring and the first spring are adopted for opening and closing; opening and closing of the valve body can be controlled according to the temperature of water flow, and the service life of the anti-freezing valve is not limited.

A system includes a variable displacement pump (VDP) in fluid communication with an inlet line and with an outlet line. The VDP includes a variable displacement mechanism configured to vary pressure to the outlet line. A bypass valve (BPV) includes a BPV inlet in fluid communication with the outlet line, and a BPV outlet in fluid communication with a bypass line that feeds into the inlet line upstream of the VDP. A minimum pressure shutoff valve (MPSOV) is connected in fluid communication with the outlet line, configured to block flow through the outlet line for shutoff. The MPSOV is connected in fluid communication with the BPV for triggering recirculation through the BPV.

A dust collection adapter (10) according to the present disclosure includes: a main body (11, 12); an internal flow path (19) that is located in an interior of the main body (11, 12) and through which a gas flows; and a plurality of ribs (17, 18) that are located in the internal flow path (19) and with which the gas introduced into the internal flow path (19) collides. The dust collection adapter (10) is mounted on an adapter-receiving component located at an inlet of a gas meter. The adapter-receiving component may be, for example, a shut-off valve (20).

The utility model provides a corrugated pipe stop check valve, which relates to the technical field of stop valves and comprises a valve main body, a water inlet is arranged on one side of the valve main body, a water outlet is arranged on one side of the valve main body far away from the water inlet, a valve rod is arranged at the top of the valve main body, and a corrugated pipe is arranged at the bottom of the valve rod. A rotating wheel is arranged at the top of the valve rod, a sealing device is arranged at the bottom of the corrugated pipe, a connecting device is arranged at the top of the corrugated pipe, the sealing device comprises an arc-shaped plate, the arc-shaped plate is fixedly connected with the inner wall of the valve body, and a rubber block is fixedly connected to the bottom of the corrugated pipe. The rubber block is extruded to one side of the arc-shaped plate, then the rubber block is extruded through the connecting strip, the water inlet and the water outlet are separated through the rubber block, a good sealing effect is achieved, and abrasion of the rubber block can be reduced to a certain degree.

A trailer control valve for controlling a hydraulic dual-line brake system of a trailer vehicle has an inlet for a hydraulic supply line of the towing vehicle, a tank outlet for an unpressurized return-flow line of the towing vehicle, a brake pressure outlet, and a supplemental pressure outlet. The brake pressure outlet can be connected in a stepped manner with an electronically controlled brake control valve to the supply pressure inlet or to the tank outlet. The supplemental pressure outlet can connect using a valve arrangement so that an outlet pressure of the supply pressure is reduced to a supplemental pressure at the supply pressure inlet or at the tank outlet. The valve arrangement has a pressure-limiting valve and a shut-off valve arranged in series. The shut-off valve can be a 3 / 2-way valve, which when not energized, the supplemental pressure outlet is connected to the tank outlet.

To provide a gas flow measurement device capable of further improving the accuracy of gas flow measurement, and a gas flow measurement system.SOLUTION: A gas flow measurement device 2 includes: a storage unit 21 that stores reference correlation values (e.g., zero reference value), which is a value corresponding to a predetermined flow rate for a correlation value having a correlation with the flow rate of gas in a flow path 13; and a control unit 20. The control unit 20 is configured such that, when the preset condition that estimates that there is no gas usage downstream of the own device is met (S3: YES), the flow path is closed by a shutoff valve 4 for a predetermined first period, and during first period, the average value of the gas flow rate is calculated by the flow rate calculation process for a predetermined second period, and execute a series of correction processing (S4-S7) to correct the reference correlation value stored in the storage unit based on the average value.SELECTED DRAWING: Figure 1

The invention discloses a stop valve based on sealing performance self-inspection, and relates to the technical field of stop valves. Comprising a valve body, a valve cover, a valve clack assembly, a valve rod, a hand wheel, a protection assembly and a support, displacement generated when a lower valve clack is closed is utilized, a sealing detection groove is automatically opened, leakage liquid is guided and collected, a detection ring is driven by the leakage liquid to move upwards, accordingly, a detection block is driven to extrude a transmission block, a piezoelectric crystal is finally triggered, leakage physical quantity is converted into quantifiable electric signals, and the leakage physical quantity is detected. And the purpose of sealing self-inspection is achieved. When the valve clack assembly is opened, the design that the lower valve clack rebounds automatically is utilized, the liquid drainage ring is driven to be embedded into the sealing measuring groove, leakage liquid in the sealing measuring groove is squeezed out, and the liquid drainage effect is achieved. The lower valve clack and the upper valve clack are made to be close to each other through downward pressure generated when the valve clack assembly is closed, the air bag ring is extruded, the air bag ring generates one-way expansion to conduct secondary sealing on the closure opening, and the multiple sealing effect on the closure opening is achieved in combination with primary sealing between the upper valve clack and the closure opening and between the lower valve clack and the closure opening.

The invention discloses a stop valve with a leakage warning structure. The stop valve comprises a valve shell, a stop structure and a sensing assembly. A water inlet, a water outlet and a stop hole connecting the water inlet and the water outlet are formed in the bottom of the valve shell, the stop structure comprises a valve rod and a valve plug, and the valve plug is sealed with the stop hole through a sealing ring. The sensing assembly comprises a soaking sensing mechanism and a soaking display mechanism. The inner wall of the stop hole is provided with a stop surface and an overflow surface; the valve plug is provided with a first separating ring, a second separating ring and an induction groove, the separating rings are provided with overflow grooves, and the induction groove corresponds to the overflow face. The immersion sensing mechanism comprises a plurality of sensing pieces in a sensing groove, the odd-digit sensing pieces and the even-digit sensing pieces are connected with two electrodes of the display mechanism respectively, and a third overflow groove is formed in the outer ring. The immersion display mechanism detects the conduction condition between the induction sheets through the operation controller, and controls the switch tube to drive the display end to work. Leakage at the sealing position of the valve plug can be detected in time and warned, and safety is improved.

In the technical field of gas water heaters, we provide a double-tank type thermostatic bubble water device. The solution includes a thermostatic tank 1 and a gas dissolution tank 2, the tops of which are connected by an upper connecting pipe 3, the upper connecting pipe is equipped with a shut-off valve 4, and the bottoms of which are connected by a lower connecting pipe 5. The thermostatic tank replenishes the water flow during gas filling, ensuring that users can use the water normally when gas is being added to bubble water, reducing the waiting time during gas addition and improving bathing comfort.

The invention discloses an unloading type low-temperature throttling stop valve and a machining method of a valve body assembly, and the unloading type low-temperature throttling stop valve comprises the valve body assembly, a valve rod assembly and an auxiliary valve element assembly; a flowing cavity is formed in the valve body assembly, the valve rod assembly can be arranged in the valve body assembly in a piston motion mode in the vertical direction, the valve body assembly is further provided with an inlet channel and an outlet channel which are communicated with the flowing cavity, and a sealing gasket is arranged at the bottom end of the valve rod assembly. The sealing gasket can abut against a sealing cutting edge at the communicating position of the inlet channel and the flowing cavity along with descending of the valve rod assembly so that face sealing can be formed. When the stop valve is used, the problems that a sealing structure of a stop valve in the prior art fails and the like are solved, and when the stop valve is closed, fluid in a cavity of the stop valve can cause the large pressure difference of an inlet and an outlet in the closing process, the closing torque of the valve in the closing process is influenced, and the rapid response of a system is greatly influenced are solved.

The present invention relates to the technical field related to valves, and discloses a stop valve, comprising a valve cover portion, a valve pipe portion being installed on the lower side of the valve cover portion, the valve pipe portion comprising a connecting valve pipe, an input chamber being provided in the connecting valve pipe, an output chamber being provided in the connecting valve pipe, a stop function chamber being provided between the input chamber and the output chamber, a stop plug being installed in the stop function chamber in a liftable and slidable manner, and an elastic wrapping portion being installed on the stop plug; the stop valve of the present invention is provided with a stop buffer function, and an elastic wrapping portion structure is provided on the upper side of the stop plug, which can form a surrounding effect on the valve stem of the transmission connection structure of the stop plug, thereby preventing the valve stem from being placed in the stop function chamber for a long time and being affected by corrosion and impact, thereby improving the effective service life of the valve.

The invention relates to the technical field of valves, in particular to an integrated double-channel stop valve which comprises a main valve body, a liquid inlet bottom cavity and a liquid outlet top cavity, the liquid inlet bottom cavity and the liquid outlet top cavity are formed in the main valve body, a valve seat ring is arranged between the liquid inlet bottom cavity and the liquid outlet top cavity, a valve element disc is arranged outside the valve seat ring, and the valve element disc moves axially through the valve element disc. The valve element disc and the valve seat ring are matched in an opening and closing mode, and therefore stopping and circulation control of the stop valve are achieved. According to the integrated double-channel stop valve, integrated pressure relief protection can be achieved, fluid pressure relief and discharge can be conducted when the pressure is too high through the additionally-arranged secondary channel, and the integration degree is improved while the safety is improved.

A storage system for storing a cryogenic medium, in particular, for storing hydrogen. The storage system includes storage container for receiving the cryogenic medium, at least one pipe projecting from outside the storage container into the storage container, and a shut-off valve in fluidic communication with the at least one pipe. The at least one pipe is closed at an end thereof facing away from the storage container and is open at another end thereof located in the storage container. The shut-off valve is moveable between an open operating state in which an inner space of the at least one pipe is in fluidic communication with an inner space of the storage container, and a closed operating state in which the inner space of the at least pipe is not in fluidic communication with the inner space of the storage container.

The invention relates to the field of natural gas, in particular to an auxiliary operation method based on an intelligent filling system, and solves the safety and benefit problems of Dewar flask filling. Liquid is guided, after a filling liquid phase valve and a gas phase stop valve are fully opened, a rear gap bridge valve of a filling station is slightly opened, and the opening degree is kept within the range of 5-15 degrees within a circle; supercooling: when the outlet temperature of the BOG gasifier is less than or equal to-20 DEG C or the airflow vibration sound of the rear gap bridge valve disappears, closing the rear gap bridge valve; filling gun heads of the liquid-phase pipeline and the gas-phase pipeline are respectively connected with a liquid-phase angle valve and a gas-phase angle valve of the Dewar flask through the connecting pipe; and releasing the pressure, slowly opening a gun head stop valve of the filling gun head of the gas phase pipeline, confirming that no leakage exists at the joint of the filling gun head, and slowly opening a liquid phase angle valve of the Dewar flask. A traditional mode is optimized and improved, the filling efficiency is improved, the refilling quality is guaranteed, the filling safety is improved, human errors are reduced through a regular process, environmental protection and economic benefits are achieved, and the design and use requirements are met.

This invention provides a fire-fighting water pipeline flow regulation device, comprising an inlet pipe, a shut-off valve for controlling the flow of pressurized water within the pipe, an adjustable filter connected to a flow regulator with a cross-sectional area, and an outlet pipe connected to the other end of the flow regulator. Hose connector end caps are fixedly installed at the ends of the inlet and outlet pipes, and an automatic pressure relief valve with upper and lower chambers is installed at the end of the hose connector end cap. This device addresses the problems of unadjustable flow and pressure, failure to automatically drain residual water leading to accelerated pipe corrosion, and lack of filtration causing blockages. It enables manual adjustment of flow and pressure within the pipe, automatic drainage of residual water, and filtration and anti-blockage of pressurized water within the pipe.

The application relates to the technical field of stop valves, and discloses an ultralow-temperature stop valve, which comprises a valve seat and a valve body, the valve seat is arranged on the valve body, a valve rod for opening and closing the valve seat is arranged in the valve body, a packing part is arranged on the valve body, the packing part is used for plugging a gap between the valve body and the valve rod, a heat preservation sleeve is arranged on the valve body, a baffle is arranged on the valve body, the heat preservation sleeve is located on the side, away from the valve seat, of the baffle, and the heat preservation sleeve is located on the outside of the packing part. The heat preservation sleeve is arranged on the valve body, the heat preservation sleeve is located on the side, away from the valve seat, of the baffle, the baffle limits the movement of the heat preservation sleeve, the heat preservation sleeve can stably preserve the temperature of the packing part, the packing part is not prone to thermal bridge effect, and the condition that the packing part can quickly adsorb cold air is reduced.

A water treatment assembly is provided comprising a filter head (12) configured for connection to a water supply line, the filter head comprising a rotatable shut-off valve (62); a sump assembly (30) releasably connected to the filter head, the sump assembly including a sump cover (32) releasably attached to a sump body (34) and defining an interior chamber (38), and the sump cover having a cover port (74, 76) in fluid communication with a complementary head port (68, 70) in the filter head; and a filter insert (40) releasably enclosed within the interior chamber, the filter insert having a filter media portion (42) and an end cap (46) secured to the media portion, the end cap having at least one port (86) configured for fluid communication with one of the cap ports and one of the head ports.

The utility model discloses a high-stability inner sealing structure of a stop valve. The high-stability inner sealing structure is characterized in that a limiting surface and a sealing surface which is connected with a valve rod, limits the moving stroke of the valve rod and has sealing performance are arranged at the bottom of a reverse sealing thread bushing; the sealing surface is arranged on the back sealing thread bushing, when the stop valve is opened, the sealing angle on the valve rod is matched with the sealing surface, the moving stroke of the valve rod is limited, meanwhile, when the sealing angle on the valve rod makes contact with the sealing surface, the back sealing thread bushing can be extruded, the back sealing thread bushing is made to be extruded outwards, and the stop valve is sealed. The sealing performance and the stability of connection between the back sealing thread bushing and the valve body are improved; through the arrangement of the high-strength sealing ring and the high-strength sealing groove, friction between the lower valve element and the interior of the valve body when the stop valve is opened and closed is avoided, the situation that the sealing performance is affected due to abrasion of the lower valve element caused by long-time friction is avoided, the sealing performance and stability of the stop valve are improved, and therefore the service life of the stop valve is prolonged.

The invention provides an online inspection and maintenance butterfly valve, which relates to the technical field of valves, and comprises a valve body and an inspection and maintenance assembly, the two ends of the valve body are fixedly connected with a front end flange and a rear end flange respectively, the valve body is provided with a maintenance assembly, and the check valve is characterized in that the maintenance assembly comprises a notch, the notch is formed in one end of the top of the valve body, and the two sides of the valve body are fixedly connected with extending convex plates. During maintenance, the main flow channel can be closed and switched to the flow dividing branch pipes to circulate media, the defect that in traditional maintenance, shutdown and flow cutoff are needed is overcome, economic losses caused by production stagnation due to shutdown are fundamentally eliminated, in addition, after limitation of the butt joint supporting plate is removed, parts in the valve body can be maintained, multiple sets of flange bolts do not need to be disassembled one by one, and the maintenance cost is reduced. The maintenance time is shortened, meanwhile, the risk of pipeline sealing failure caused by disassembly and assembly of a connecting bolt of the valve body and the pipeline is avoided, and the sealing performance of the pipeline is guaranteed.

A tank device for temperature pressure relief of a gas storage tank, wherein the tank device comprises at least two tank containers and a delivery line connectable with the tank containers. Each of the at least two tank containers has at one end at least one shut-off valve arranged between the respective tank container and the delivery line, wherein at the other end of the tank container at least one safety valve is arranged. On the tank container a mesh element consisting of electrical lines and other electrical lines is arranged, wherein the electrical lines have a longitudinal axis which differs from the longitudinal axis of the other electrical lines. Here, the electrical lines and the other electrical lines form electrically insulated nodes. Furthermore, the mesh element and the tank container have no electrical contact. The invention also relates to a fuel cell system, a fuel cell operated vehicle and a hydrogen operated vehicle.

A drinking and domestic water system with a transfer point (22) from the public water supply network, a line (2, 4) from which at least one ring main (10; 38, 40) branches off, wherein the ring main (10) branches off from the line (2, 4) via an outlet opening (14) and is led back into the line (2, 4) via an inlet opening (16), wherein a flow resistance element (36) is arranged in the line (2, 4) between the outlet opening (14) and the inlet opening (16), or wherein the ring main (38, 40) is led back into a circulation line (6) via the inlet opening (16). The present invention aims to provide such drinking and domestic water system, which is intended to simplify the shutting off of the ring main for functional tests, cleaning measures or maintenance purposes.

The utility model discloses a zero leakage stop valve relates to stop valve technical field, including stop valve body, the both ends of stop valve body are provided with connecting pipe, the inside of connecting pipe is inserted and connected with the delivery pipe, the inner wall of two connecting pipe is provided with two annular sealing groove in the surrounding mode, and the annular sealing groove is connected with the delivery pipe. Annular sealing grooves are formed in the two connecting pipes, annular sealing rings are arranged in the two annular sealing grooves, each annular sealing ring is matched with the corresponding conveying pipe, the pipe walls of the two connecting pipes are slidably sleeved with sealing covers, and sealing mechanisms are arranged between the two connecting pipes and the sealing covers; and two first arc-shaped grooves are symmetrically formed in the inner walls of the two sealing covers. According to the stop valve, the two connecting pipes are connected to the outer surfaces of the corresponding conveying pipes in a sleeved mode respectively, then the two annular sealing rings can play a dual-sealing role, and therefore the phenomenon of leakage at the two ends of the stop valve body can be prevented.