73results about How to "Eliminate cavitation" patented technology

The invention provides a device for eliminating cavitation in the excess fuel return orifice(s) in the compression chamber of a fuel injection pump of an internal combustion engine after the end of the injection stage, said injection pump being connected firstly to a feed duct including a first check valve having low headloss enabling fuel to reach the compression chamber, and secondly to an excess fuel return duct, wherein the return duct comprises in parallel and close to the return orifice of the injection pump, a second check valve that is rated to cause the pressure in said return orifice of the injection pump to rise, and a two-port valve that is normally open and that is caused to close by the appearance of pressure in the return orifice greater than the pressure which obtains in the feed duct upstream from said first check valve.

The invention relates to a vacuum backflow electrolysis processing method and a vacuum backflow electrolysis processing device which belong to the technical field of electrolysis processing. The method adopts a backflow liquid supply way in the process of electrolysis processing; and electrolyte enters a front gap from a side gap of a processing area to participate in reaction and is finally discharged from an electrolyte passage in a tool electrode. The vacuum backflow electrolysis processing method is characterized in that the backflow liquid supply way is realized by a pumping function of a vacuum generating device. The method and the device are significant for improving the stability and the processing efficiency of electrolysis processing.

The invention relates to a dual-pressure expansion organic rankine cycle (ORC) mid-low-temperature waste heat recovery power generation system and belongs to the technical field of energy and environments. According to the system, mid-low-temperature waste heat flue gas with the temperature being 200-350 DEG C is utilized as the driving heat source, organic working medium feeding liquid is preheated to be in a saturated liquid state in an ORC waste heat boiler preheating segment, then part of a saturated liquid organic working medium enters an evaporation segment and an superheating segment ofa waste heat boiler, generated saturated (or superheated) steam enters a radial-inward-flow turbine, and a high-pressure stage ORC expansion work doing process is completed; and the other part of thesaturated liquid organic working medium enters a flash vessel after being subjected to throttling and pressure reducing, saturated steam separated from the flash vessel enters a low-pressure stage screw expander, and a low-pressure stage ORC expansion work doing process is completed. An ejection compressor recovers the liquid-phase working medium separated out of the flash vessel, utilization ofliquid conveying pumps is reduced, the system is simplified, and the possibility of pump cavitation is eliminated.

The invention provides an impact-resistant and anti-wear agent for hydraulic concrete, which mainly comprises a nano material, slag, latex powder, rubber powder, a water reducing agent, fibers, an exciting agent and a defoaming agent. The impact-resistant anti-wear agent is suitable for places such as water conservancy projects, roads and airport pavements requiring high impact-resistant and anti-wear concrete, has the functions of resisting crack, reducing water, reinforcing and reducing elasticity, and excellent mixing and constructing properties. The impact-resistant and anti-wear agent has the advantages of increasing concrete impact-resistant and anti-wear properties, prolonging maintenance period and reducing maintenance cost.

A fluid working machine comprises a controller (12) and a working chamber (2) of cyclically varying volume. The working, chamber has both an electronically controllable primary low pressure valve (14) and a secondary low pressure port (22) associated therewith, each of which is openable and closable in phased relation to cycles of working chamber volume to bring the working chamber into fluid communication with a low pressure manifold (16, 26). At least the primary low pressure valve is under the active control of the controller to enable the controller to determine the net displacement of fluid by the working chamber on a cycle by cycle basis. The primary low pressure valve and the secondary low pressure port are openable concurrently during a portion of at least some cycles of working chamber volume to enable fluid to flow into or out of the working chamber concurrently through both the primary low pressure valve and the secondary low pressure port. The primary low pressure valve may be closed under the active control of the controller a period of time after the secondary low pressure port closes.

The invention relates to a damping noise reduction valve plate for a plunger hydraulic pump. The damping noise reduction valve plate for the plunger hydraulic pump comprises a valve plate body which is provided with a low pressure oil suction area and a high pressure oil discharging area, wherein the low pressure oil suction area and the high pressure oil discharging area are isolated from each other and are symmetric relative to a horizontal shaft of the valve plate body. The two ends of the low pressure oil suction area and the two ends of the high pressure oil discharging area are respectively communicated with a triangular groove. A damping hole is formed in the bottom of the top end of the triangular groove, an oil channel is formed in the bottom of the damping hole, and the oil channel is communicated with an inner cavity of a pump shell through the cylindrical side face of the valve plate body. The oil channel is composed of a vertical section oil channel and a horizontal section oil channel. Through the arranged oil channel, bubbles generated in the working process and bubbles sucked in can be timely discharged into the cavity of the pump shell, and therefore cavitation, noise and vibration caused by bubble breakage are lowered. The damping noise reduction valve plate for the plunger hydraulic pump obviously improves the cavitation resistance of the plunger pump, and has the advantages of being small in vibration, low in noise, good in working stability and the like.

The invention relates to the use of gas cavities to reduce frictional drag on underwater surfaces such as hydrofoils, struts, fins, rudders, keels, propeller blades, ship hulls, underwater bodies, and wetted surfaces in general. Each gas-filled cavity is formed behind a discontinuity in the surface that causes the water boundary layer to separate from the surface. Gas is ejected into a region behind the discontinuity to fill the cavity; the gas can be air. If a cavity is open to the atmosphere, then air can typically fill the cavity naturally without air ejection. Cavities can either be closed or open. A low drag hydrofoil may have a closed cavity on one side, and an open cavity on the other side. For closed cavities, the underlying surface can be shaped to minimize cavity closure drag. Various ways to generate cavities, change hydrodynamic forces, and duct gas internally on hydrofoils and struts with cavities are covered. Different designs of hydrofoil boats, hydrofoil ships and ship hulls that are amenable to drag reduction are presented.

Coal mine excavation face often causes roof fall accidents due to changes in geological conditions, inadequate support measures, and poor management. For large-scale roof fall accidents, they often cannot be handled well. The usual method is to clear out the working passage in the roof-fall area, and the personnel go deep into the top of the roof-fall area to install anchor rods and anchor cables and erect wooden pile roofs. This approach requires a large amount of labor, difficult construction, poor safety, a large amount of gangue cleaning, and the hidden danger of gas accumulation in the roof fall area. Therefore, the present invention proposes a grouting treatment method for the high risk area of ​​the excavation face. The method includes three technological processes of constructing a blocking wall, subarea grouting, and shed clearing. This method does not require workers to go deep into the roof fall area to operate, the amount of gangue cleaning is small, the cavity of the fall is eliminated, and the risk of gas accumulation is eliminated. It has a good reinforcement effect on gangue in the roof fall area, and the slurry spreads more evenly. Low material consumption and low cost.

The invention provides an oil-gas suspension cylinder and a vehicle. The oil-gas suspension cylinder comprises a cylinder barrel, a throttling piston, a piston rod and a pneumatic piston, wherein thethrottling piston is arranged in the cylinder barrel, and is used for partitioning the space in the cylinder barrel into a roded cavity and a rodless cavity; the piston rod is located in the roaded cavity, and connected with the throttling piston; a piston rod barrel cavity is formed in the piston rod; the pneumatic piston is arranged in the piston rod barrel cavity slidably; the piston rod barrelcavity is partitioned by the pneumatic piston into a throttling cavity and a gas cavity independent of each other; and the throttling cavity is adjacent with the rodless cavity and communicates withthe roded cavity. Due to the technical scheme of the oil-gas suspension cylinder, oil-gas separation in the oil-gas suspension cylinder is effectively achieved, so that damping force in two directionsin the oil-gas suspension cylinder is more balanced, and the driving stability of the vehicle can be kept easily; the oil-gas ratio can also be accurately controlled, inflating and deflating are moreconvenient and faster, and maintaining is convenient; and cavitation by mixed gas in oil liquid on sealing pieces and parts can also be eliminated, and the service life of the oil-gas suspension cylinder is prolonged.

The invention provides a delivery elbow pipe and a production method thereof. The delivery elbow pipe comprises an outer elbow pipe (3), an inner elbow pipe (2) and a connecting flange, wherein the inner elbow pipe (2) is made of abrasion resisting materials and embedded inside the outer elbow pipe (3), at least one end of the inner elbow pipe (2) extends out of the outer elbow pipe (3) from the end portion of the outer elbow pipe (3), and the connecting flange is sleeved on the outer side of the end portion of the inner elbow pipe (2) and fixedly connected with the inner elbow pipe (2) and/or the outer elbow pipe (3). By means of the delivery elbow pipe, an abrasion resisting material layer integrally formed by the inner elbow pipe is free of seam, so that the delivery elbow pipe is capable of avoiding eddy caused in the position of the seam in the prior art and removing cavitation caused by the eddy accordingly.

The invention relates to an array flow velocity control valve structure suitable for incompressible fluid. The structure comprises a valve body, a valve base, valve cores, an upper cover and valve rods, wherein the base valve is arranged in the valve body, a plurality of throttle slices are arranged installed on the valve base, the throttle slices are positioned through positioning pins, each of the throttle slices comprises a parallel thin plate body and a rhombic pillar-shaped array structure, a guide base is installed on the throttle slices, balancing sealing rings are installed in the guide base, valve cores are installed in the throttle slices, the valve cores are connected with the valve rods, and the upper cover is installed on the valve body; and the upper cover is fixed on the valve body through a screw bolt and a nut. According to the structure, the fluid pressure is kept to be above the saturated vapor pressure, bubbles are avoided, and a cavitation phenomenon is eliminated; damages of inner parts of a valve, which are caused by energy blasting energy, are reduced; the valve is convenient to disassemble and clean, and on-line maintenance is facilitated; and the pressure is reduced step by step through flow rate control of high-speed incompressible fluid, the cavitation phenomenon is avoided, and the normal operation of the valve is guaranteed.

The invention discloses an ultra low temperature nitridizing method for a large ship engine cylinder sleeve, comprising the steps as follows: (1) towel is used to clean up the oil stain on a work piece; (2) the work piece is put into a clamping apparatus; (3) the work piece is put into a decontamination agent tank to carry out oil coating at the temperature of 75-95 DEG C for 5-8min; (4) the coated work piece is washed by running water; (5) the work piece is preheated at the temperature of 200-250 DEG C for 50-60min; (6) Na2SO4 with the weight of 8% is added into the nitridizing agent in the nitridizing furnace; the nitridizing temperature is 350 plus/minus 5 DEG C and the period is 2.5-3h; (7) the nitridized work piece is cooled in the air to below 150 DEG C; (8) the work piece is washed by running water; (9) the nitridized cylinder sleeve is checked; (10) the qualified cylinder sleeve is soaked into rust preventative oil; (11) the soaked cylinder sleeve is packaged and stored for transportation. The invention adopts low temperature nitrogen treatment, so that the nitridizing period is shortened, the production cost is lowered, and the product quality is improved, thus being suitable for industrialized mass production.

A gear pump is provided with a drive gear rotated via a drive shaft; a slave gear; a gear housing containing a gear chamber housing these gears therein; and a pump housing composed of a cylindrical housing main body with a bottom which contains the gear housing for serving as a low pressurized chamber, the inside of which communicates with the gear chamber, and an opening being defined thereon, and a covering member for closing the opening, wherein an eccentric pitted portion being eccentric with respect to the axis of the drive shaft is defined on the covering member, and the fluid return port is allowed to face to the eccentric pitted portion to function the eccentric pitted portion as a return fluid passage for return fluid, whereby it is possible to reduce a size of the gear pump without accompanying any cavitation.

The invention discloses a high-pressure multi-stage pressure reducing valve. The high-pressure multi-stage pressure reducing valve comprises a shell, wherein a fluid inlet and a fluid outlet are arranged on the shell; a plurality of sealing bosses are arranged on the inner side of the shell; a groove is formed between every two sealing bosses; the multi-stage pressure reducing valve further comprises a valve core connected to the sealing bosses; a plurality of guiding grooves are formed in the valve core; the number of the guiding grooves is equal to the number of the grooves; the axially adjacent guiding grooves are arranged with an angle alpha, and of the angle alpha is greater than 0 DEG and less than or equal to 90 DEG; the guiding grooves are radially and symmetrically arranged with every two guiding grooves falling into one group; a flow guiding bevel is arranged on the surface, away from the fluid inlet, of each guiding groove; chamfers are arranged on the inner side of the sealing boss at the fluid inlet of the shell; and a rounding is arranged on the end, near to the fluid inlet, of the valve core. When the high-pressure multi-stage pressure reducing valve is connected tothe fluid, the distance between the chamfers and the rounding is larger than the distance between the flow guiding bevels to the sealing boss closest to the flow guiding bevels. The high-pressure multi-stage pressure reducing valve is suitable for high pressure fluid, and is also suitable for low pressure fluid.

The invention belongs to the field of ship or rudder design and particularly relates to an anti-cavitation twisted rudder and a design method thereof. On the basis that the influence of various factors such as the rotational speed in the ship propeller wake flow on the rudder is fully considered, the geometrical attack angles and line types of all the spanwise position sections are designed and determined through the distribution characteristic of a propeller rear wake flow field in direct sailing of a ship, so that the geometrical shape of the rudder is matched with that of the propeller wake flow field, and the purposes that the pressure distribution of the rudder surface is improved, the cavitation starting sailing speed of the rudder is increased, the time of rudder cavitation is shortened, the area of rudder cavitation is decreased, vibration and noise caused by the rudder are reduced, cavitation denudation of the rudder surface is restrained, the maintenance cost of the rudder is saved, the force state of rudder blades is improved, the rudder efficiency is improved, and the load of the rudder is reduced are achieved.

The invention provides a ball valve for eliminating cavitation, relates to the field of pipeline control valves, and is used for solving the problem of damage to internal parts of the valve caused by the cavitation phenomenon in the existing ball valve. The ball valve for eliminating cavitation includes a first valve body part, a second valve body part, a valve stem, a ball, a valve seat, a spring and a fixed shaft, and also includes a spherical wall plate with a through hole, and the spherical wall plate partially covers on the outlet flow path of the sphere. The ball valve for eliminating cavitation can effectively eliminate cavitation when the opening is small, and can meet the greater flow requirements of the valve when the cavitation is not obvious when the opening is large, and the structure is simple, easy to process, and easy to assemble. Energy-saving and high-efficiency features.

A blending appliance is provided including a motorized base, a blending container, and a blade assembly fitted into an opening of the blending container and rotatably coupled to the motorized base when the blending container is mounted on the motorized base. The blade assembly includes a lower blade element disposed on a spindle performing blending operations on ingredients at a lower end of the blending container; and an upper working element disposed on a shaft spaced apart from the lower blade element, and including an upper working portion and a lower working portion spaced apart from the upper working portion. The upper working portion acting to reduce cavitation in the lower blades element during the blending process.

The invention discloses a pump drive cavitation self-repairing large-scale two-phase flow cooling system and a method thereof.The system comprises an evaporation cold plate of electronic equipment and a condenser, the evaporation cold plate of the electronic equipment is connected with the condenser, the condenser is connected with a liquid storage tank, a liquid level sensor is arranged in the liquid storage tank, and the liquid level sensor is connected with the evaporation cold plate of the electronic equipment; two pipelines are arranged at the bottom of the liquid storage tank and connected with a liquid supplementing tank, a liquid return one-way valve is arranged on one pipeline, a liquid supplementing one-way valve is arranged on the other pipeline, a refrigerant filling opening is formed between the liquid return one-way valve and the liquid supplementing tank, a liquid supplementing pump is arranged between the liquid supplementing one-way valve and the liquid supplementing tank, and a liquid supply pump is connected to the bottom of the liquid storage tank. And the liquid supply pump supplies liquid to an evaporation cold plate of the electronic equipment. Self-repairing and self-starting of the pump after cavitation are achieved, and the engineering applicability and reliability of a large two-phase flow cooling system are improved.

The invention provides a ball valve controlling cavitation and belongs to the technical field of pipeline control. The ball valve controlling the cavitation is used for solving the problem that an existing ball valve is prone to generating the cavitation. The ball valve controlling the cavitation comprises a valve body composed of a first valve body portion and a second valve body portion, a sphere, a valve rod, valve seats, springs and a fixing shaft, wherein the sphere, the valve rod, the valve seats, the springs and the fixing shaft are located between the first valve body portion and the second valve body portion. The fixing shaft is located on the lower side of the sphere and used for supporting the sphere. The valve rod is connected with the sphere and used for driving the sphere to rotate. Spherical surface seal is formed by the sphere and the valve seats on the left and right sides. The springs are arranged on the outer sides of the valve seats and used for pressing the valve seats to the sphere. The ball valve further comprises a valve element which is arranged on an outlet flow channel of the sphere in a tightly attached manner. The valve element is provided with a channel extending in the direction of a ball valve flow channel. The ball valve controlling the cavitation can effectively restrain generation of the cavitation and is beneficial for lowering of noise and vibration generated by fluid.