Solenoid valve actuator assembly is the main form of electronic jacquard opening,

With the improvement of living standards, people dress fabric requirements are also increasing , making the needle can produce a large number of high-grade fabric , the rapid development of high-speed electronic jacquard machine . Solenoid valve assembly is formed mainly electronic jacquard actuator opening, a jacquard  Instrumentation ball valves  to thousands pack assembly , its quality directly affects the reliability of the quality of the fabric and production efficiency. Today, there are four main jacquard production companies in the world , they each have their own solenoid valve assembly . Our After years of research, the use of domestic raw materials, combined with the actual production process of the factory,   Double ferrule fitting  improvement and optimization, has successfully developed electronic jacquard solenoid valve assembly used . The structure of this component by 8 Electromechanical Components needle selection unit , each unit includes a needle selection solenoid valves, two fixed hooks, two spring hooks , 2 Needle , a consolidated block back , a briquetting spring , a group composed of the pulley rope . Each needle selection unit controls the same set of warp tissue , compared to other types of electronic jacquard his electromagnetic valve structure allows the use of this combination is arranged inside the electronic jacquard machine is more compact and reasonable to reduce energy consumption ; simple structure easy to disassemble , easy maintenance and replacement ;

Standardized prefabricated manifold forms, changed some of the limitations of the past in the field of direct production and installation

Philatelic oil, set to close the ball valve petrol station inside and oil and gas gathering pipelines, are used in the form of standardized prefabricated valve, changed in the past in the field of direct production and installation of some limitations. Project site assembly is relatively reduced, adverse effects of climate and other factors is small, while the dismantling of prefabricated valve interchangeability with regularity and speed up the construction progress. Reasonable to avoid the aerial assembly. Narrowing the range of operations, reducing the security  Stainless steel needle valve . Prefabricated valve materials are mostly carbon steel, stainless steel; in the number of low-pressure pipelines primarily to a relatively small proportion of high-pressure pipelines; presence of a large number of saddle mouth open system workload; butt weld seam in the form of the main;  Instrument valve manifolds  for welding high. To ensure the quality and performance of our valve products and processes using reasonable prefabricated welding backing, automatic welding cap surface welding process. And distortion factors to be produced during welding and lifting analysis to take effective control measures.

Prefabricated metering valve between the process, according to the condition of the structure, characteristics and possible causes deformation produced

During the welding process , the structure is subjected to uneven heating and cooling , the metal parts of different degrees of expansion and contraction . Metallic material as a whole, interrelated, mutual restraint, elongation and shortening are not free , so the welding process will produce stress and deformation . Welding deformation leads to the size and shape of the weldment changes directly affect the manufacturing quality . If the distortion exceeds the normal range , you need to rework correction processing , reduce work efficiency, but also increase the cost of production. Between the metering valve prefabricated process, depending on the situation should be carefully analyzed its structure ,  Stainless steel needle valve  and possible causes deformation , select a reasonable measures to control the deformation process , meet the technical standards in order to improve the effectiveness and reduce unnecessary losses . When the valve between the measured deformation reason prefabricated , conducted at the Department of  Instrument valve manifolds  tube cutting and welding are localized uneven heating process . Cutting and welding , thermal expansion of the high temperature region , hindered by the rigidity of the surrounding area and can not freely low elongation , resulting thermoplastic deformation. Upon cooling, the high-temperature region due to shrinkage of the thermoplastic deformation of the large amount of shrinkage in a low temperature region is small, this causes uneven shrinkage generated manifolds condensed bending.

The causes valve preform deformation process may be analyzed

Prefabricated manifold for reasons that may arise during deformation are analyzed to select a reasonable anti-deformation process measures to control the deformation, to meet the standards and requirements in order to improve effectiveness and reduce losses. Deformation analysis valve manifold reasons prefabricated pipe saddle on the mouth of the Department oxygen acetylene cutting and welding, are  Instrument valve manifolds  and cooling, the thermal expansion of the high temperature region, the rigidity of the low-temperature region by the surrounding obstacles can not be stretched freely long, resulting thermoplastic deformation. When cooled, high-temperature thermoplastic deformation of the area due to contraction of large, low-temperature region produces a small amount of shrinkage, this  High pressure ball valve  to contraction of the portal produce condensed riser bending and angular distortion arising condensation. Simultaneously welded fast heating and rapid cooling, high temperature region of the tissue changes, the corresponding change in volume will occur, resulting in tissue deformation. Condensed deformation and deformation of the joint action organization, making the valve sink pipe bending deformation riser manifolds on angular distortion generated.

Plastic air intake manifolds that is the vehicle structural member is complex, and requires high functional element is

Automotive plastic has the general trend garnish and upholstered structure and function of the steering member, i.e., the plastic intake manifold is very complex automotive structural parts and functional parts are demanding. At present, the domestic design and manufacture of plastic intake manifold technology does not pass. This article is part of the research and development of plastic intake manifold methods. For the domestic is still not self-designed plastic intake  Instrument valve manifolds  mold. Authors believe that the use of CAE technology must advance on plastic intake manifold injection molding process simulation study, in order to achieve the success of this mold design. For plastic intake manifold,  Valve manifold  is difficult. Firstly, the Charade car engine carried a plastic intake manifold runner design simulation, mainly studied under different program number and location of the deformation, bubbles, weld lines, etc., come in the form of four water filling points for the best and to determine the best location of the gate.

Structures of complex shape plastic intake manifold has been widely applied

In recent years, the high efficiency of the engine , reduce fuel consumption , improve performance and reduce exhaust emissions have become increasingly demanding situations , conventional engine design concepts are constantly updated. As for the engine performance , fuel consumption and other aspects important part of one huge impact - the engine intake system , particularly intake manifold design requirements are constantly improved, some highly integrated, complex plastic structural shapes intake manifold tube has been widely used. Plastic  Instrument valve manifolds  wall is smooth , to reduce air resistance , easier to design the engine according to the performance requirements of complex structure and shape , can effectively enhance the engine power , improve the economy and emissions , while light weight plastic intake manifold , material and  High pressure ball valve  low cost. Engine intake manifold plastic technology is a global trend . Engine development project in the background , in the 1.3-1.5L engine passenger cars on the basis of the design study of the plastic intake manifold . First, the impact of the engine intake system of ventilation process conducted in-depth research , focusing on the dynamic effects of the intake and exhaust gas pipelines , gas flow intake system energy losses exist two aspects , the proposed intake manifold overall design ideas.

Plastic intake manifold light weight, low material and manufacturing costs, smooth wall, the air flow resistance can be reduced

Plastic intake manifold light weight , low material and manufacturing costs , smooth wall , the air flow resistance can be reduced to improve engine performance , economy and emissions improvement . Currently , gasoline plastic intake manifold design technology has matured , the country already independent research and mass production, while diesel plastic intake manifold design is still in its infancy. Plastic instead of metal as a car engine intake manifold material , the intake manifold is the trend of the development lies. However, in the design and  Instrument manifolds  of the intake manifold , the assembly of the research is the development process is often overlooked issue. This article will be mounted design ideas throughout the plastic intake manifold design is always , can be assembled primarily through the design and evaluation , research and analysis of the plastic intake manifold can be assembled . First, the structure and  Stainless steel needle valve  the engine and the intake manifold is analyzed . Followed by the assembly from the engine , and the engine intake manifold assembly , the assembly and maintenance of four intake manifold intake manifold accessories detailed analysis of the engine intake manifold assembly process and assembly difficulty. Explore again from the subsidiary parts, assembly sequence , ergonomics and summarizes the evaluation of three engine intake manifold assembly of quality standards and principles , focusing on human-computer engineering from the engine intake manifold assembly were studied .

Mathematical models at different valve opening degree, aimed at digital electro-hydraulic proportional controller design has excellent control performance...

Electro-hydraulic proportional control technology with high control accuracy, easy adjustment, the relative electro-hydraulic servo valve, with a better price advantage, currently in the industrial field, heavy machinery and other production areas have a more widely used. Electro-hydraulic proportional control of the core technologies in the closed-loop algorithm design, flutter superimposed signals, dead-time control and so on. On the basis of analyzing the characteristics of the proportional flow valve, the establishment of a mathematical model of the valve opening at different degrees, aimed at digital electro-hydraulic  Instrument valve manifolds  controller design has excellent control performance. Proportional flow valve core structure diagram is generally proportional flow by the throttle valve heart, springs, and some contain pressure compensator. This paper studies the proportional flow valve composed by the three-part series,  Compression fitting  principle. Spool movement to establish the mechanical model paper analyzes the influence of the force spool only steady state, ignoring the transient fluid dynamics and the oil outlet steady flow force, mainly analyzes the electromagnetic force, the inlet steady flow force, the spring force , fluid pressure.

Compound turbo system can achieve a good match with the diesel engine in the whole range of operating conditions, improving diesel power

Energy shortage and environmental pollution are two major challenges that face the world today, the development of efficient, clean diesel engine is a key issue in the study. Conventional exhaust gas turbocharger is difficult taking into account the high-speed, low-speed diesel engine operating conditions, the simultaneous existence of part-load economy and acceleration performance and poor. Compound turbo system can be implemented in the whole operating range of diesel engines with a good match, improving the engine power, economy and emissions, has drawn  Stainless steel needle valve  at home and abroad. Firstly, the use of software to establish a composite turbocharged diesel engine simulation model and numerical simulation. The simulation results show that the composite turbocharged engine to improve low-speed, high-speed power and economy. Meanwhile, the composite obtained by numerical simulation turbo intake system and exhaust bypass valve bypass valve control strategy provides a reference for the trial.  2 way manifolds  optional turbocharged, engine bench tests conducted research complex turbocharged. Were matched based on the high-pressure stage turbocharger optimal fuel economy principles. Composite turbocharged program conducted to determine control strategies of different speed and load, the effect of the exhaust bypass valve and the intake bypass valve opening on engine performance, determine the total working conditions and wastegate intake bypass valve opening degree control.

Compound turbo system can achieve a good match with the diesel engine in the whole range of operating conditions, improving diesel power

Energy shortage and environmental pollution are two major challenges that face the world today, the development of efficient, clean diesel engine is a key issue in the study. Conventional exhaust gas turbocharger is difficult taking into account the high-speed, low-speed diesel engine operating conditions, the simultaneous existence of part-load economy and acceleration performance and poor. Compound turbo system can be implemented in the whole operating range of diesel engines with a good match, improving the engine power, economy and emissions, has drawn  Stainless steel needle valve  at home and abroad. Firstly, the use of software to establish a composite turbocharged diesel engine simulation model and numerical simulation. The simulation results show that the composite turbocharged engine to improve low-speed, high-speed power and economy. Meanwhile, the composite obtained by numerical simulation turbo intake system and exhaust bypass valve bypass valve control strategy provides a reference for the trial.  2 way manifolds  optional turbocharged, engine bench tests conducted research complex turbocharged. Were matched based on the high-pressure stage turbocharger optimal fuel economy principles. Composite turbocharged program conducted to determine control strategies of different speed and load, the effect of the exhaust bypass valve and the intake bypass valve opening on engine performance, determine the total working conditions and wastegate intake bypass valve opening degree control.

Compound turbo system can achieve a good match with the diesel engine in the whole range of operating conditions, improving diesel power

Energy shortage and environmental pollution are two major challenges that face the world today, the development of efficient, clean diesel engine is a key issue in the study. Conventional exhaust gas turbocharger is difficult taking into account the high-speed, low-speed diesel engine operating conditions, the simultaneous existence of part-load economy and acceleration performance and poor. Compound turbo system can be implemented in the whole operating range of diesel engines with a good match, improving the engine power, economy and emissions, has drawn  Stainless steel needle valve  at home and abroad. Firstly, the use of software to establish a composite turbocharged diesel engine simulation model and numerical simulation. The simulation results show that the composite turbocharged engine to improve low-speed, high-speed power and economy. Meanwhile, the composite obtained by numerical simulation turbo intake system and exhaust bypass valve bypass valve control strategy provides a reference for the trial.  2 way manifolds  optional turbocharged, engine bench tests conducted research complex turbocharged. Were matched based on the high-pressure stage turbocharger optimal fuel economy principles. Composite turbocharged program conducted to determine control strategies of different speed and load, the effect of the exhaust bypass valve and the intake bypass valve opening on engine performance, determine the total working conditions and wastegate intake bypass valve opening degree control.

Heat load and close when burning diesel, turbocharger boost pressure control and economy-related

When the natural gas used in gasoline engines may be appropriate to increase the compression ratio, ignition timing and engine supercharger strengthened. In order to reduce emissions and improve fuel gas economy, the lean gas engine by way of control of NOx emissions, the use of  Stainless steel needle valve  produce higher power output, the thermal load near the diesel fuel and turbocharger boost pressure control and related economic . Often work in small engine load, the load is determined by adjusting the degree of  Instrument valve manifolds  of the throttle body, throttle body is generally mounted on the intake manifold, throttle pressure before the small load will be much higher than the intake manifold pressure, inlet pressure booster form does not form useful work on the engine, and therefore, the need to boost pressure under small load control to reduce fuel consumption.

Centrifugal fans are an important part of the oil cooling system for a high-performance helicopter

Centrifugal fan is an important part of high-performance helicopter oil cooling system, which drive the cold air through the oil cooler, took over the transmission system cooling oil heat, ensure the normal operation of helicopter main reduction system.  Instrumentation ball valve  fan performance the quality of the oil radiator as well as the efficiency of the entire oil system plays a vital role as an engine oil cooling system components helicopters, centrifugal fan with low flow, high pressure, high speed, small size Features This article based on the characteristics of a  Instrument valve manifold  a fan, a detailed analysis of the design parameters of the basic structure and calculation, blade profile, the preparation of the versatility of the design software, the use of technology to achieve the automatic generation of the impeller three-dimensional graphics, and gives the design instance.

Small high-pressure centrifugal fans are widely used in the production of agricultural products and feed processing

Small high-pressure centrifugal fans are widely used in the production of agricultural products and feed processing. It is the air transportation of grain and. Grind materials, feed and tea important equipment, but also some agricultural fluidized drying equipment necessary. Common fluidized drying machines, requiring its work in optimal flow velocity (apparent wind), which requires changes in load or when dry materials that increase or decrease the amount of wind  Instrument valve manifolds . According to the working principle of the fan performance curve and the pipe resistance curve of intersection of the fan for the fan's operating point, thus changing the substance of the air volume is to change the fan operating point. Small wind turbines used to change the throttle and speed control are two ways to change the amount of wind. In order to reduce the fan shaft power,  Instrument manifolds  is placed in the fan inlet side of the tube, by varying the valve angle (ie, changing the opening) to achieve increased pipe resistance off a small butterfly, the characteristic curve of the pipe. Adjustment method, although the increase the butterfly losses, there is no economic side, but because the method is simple, reliable, easy to operate, the scope of the requirements in the regulation on small wind turbines are still too large widely used.

Stainless steel needle binding file for some exploring ways

Stainless steel needle binding file for some way to explore is to do a presentation, for reference. File binding job requirements. (1) integrity. Whether it is based on the volume or stapling finisher, make sure the file is complete full page binding. Security (2) file entity. Try not to ask the destruction of files  Instrument manifolds  entity, an entity not to file damage, on the other hand to ensure the relative safety  Instrument valve  and physical binding file. (3) To facilitate the use of the file. On the one hand to facilitate the use of archives staff provides file services, on the other hand facilitate the information needs of those who use the file archives information. High (4) efficiency. Archives staff to complete the work as much as possible in the shortest binding file. 2 Binding method currently used file exists insufficient.

Soft spool off easily, more difficult to deal with

As the valve core material is soft PVC, low strength, deformation, coupled with the use of the stem and the valve plug socket  Instrument valves , not only with the two facets, and the stem easy displacement. Thus, soft spool off easily deal with them more difficult. To this end, in the end face of the original spool of welding a piece of  Compression fitting  plate, completely solve the problem of the spool off. The specific method is to remove the spool system with a hard thick PVC plate stiffeners do smm, its outer diameter smaller than the outer diameter of about spool 10mm, to facilitate welding; width slightly larger than the diameter of the stem to facilitate flexible stem rotation.

Soft spool off easily, more difficult to deal with

As the valve core material is soft PVC, low strength, deformation, coupled with the use of the stem and the valve plug socket  Instrument valves , not only with the two facets, and the stem easy displacement. Thus, soft spool off easily deal with them more difficult. To this end, in the end face of the original spool of welding a piece of  Instrument manifolds  plate, completely solve the problem of the spool off. The specific method is to remove the spool system with a hard thick PVC plate stiffeners do smm, its outer diameter smaller than the outer diameter of about spool 10mm, to facilitate welding; width slightly larger than the diameter of the stem to facilitate flexible stem rotation.

Soft spool off easily, more difficult to deal with

As the valve core material is soft PVC, low strength, deformation, coupled with the use of the stem and the valve plug socket  Instrument valves , not only with the two facets, and the stem easy displacement. Thus, soft spool off easily deal with them more difficult. To this end, in the end face of the original spool of welding a piece of  Instrument manifolds  plate, completely solve the problem of the spool off. The specific method is to remove the spool system with a hard thick PVC plate stiffeners do smm, its outer diameter smaller than the outer diameter of about spool 10mm, to facilitate welding; width slightly larger than the diameter of the stem to facilitate flexible stem rotation.

Tensile shear bolt connector can be used and compression fittings specimen specimen

Tensile shear bolt connector can be used and compression fittings specimen specimen to determine the shear capacity of a single bolt. Tensile shear specimen joint compression fittings capacity than the specimen is low. This is because the connector in the stretching tension bolt shaft is reduced, and the connector cover in the stretching  High pressure ball valve  open, the result of reduced friction. Experiments show that both for low-alloy carbon steel bolts or bolt, bolt tension specimens in shear  Instrument manifolds  of about 62% of the tensile strength of steel bolt and compression specimens was 68%. When one or two tension specimen surface in the screw pattern shear zone, then press the bolt shear capacity decreased in proportion to the net section.

Fixed abrasive grinding technology that is high speed grinding technology to replace the traditional automobile brake master cylinder master cylinder honing

Application of new technologies that fixed abrasive grinding speed grinding technology to replace the traditional automobile brake master cylinder master cylinder honing and  High pressure ball valve  this new machine grinding technology is the current important issues need to be resolved. In this paper, the master cylinder brake master cylinder  Instrument valve manifolds  equipment. Mainly includes the following aspects: (1) the overall design of the machine to determine the overall layout of the machine and the machine parameters, rendering the whole machine solid model of the machine bed modal analysis; (2) an important institution for machine tools - spindle and feeding mechanism design ideas, components location, such as the action to be accomplished is described in detail, and the spindle and the feed mechanism to establish three-dimensional solid model;

After the explosion in a confined space aluminum aerosol particle size spectrum and its produce changes over time

Plutonium oxidation at different temperatures size particles varies with temperature . Generally produce plutonium wire explosion PM2.5 ( particle size less than 2.5μm) particles , the particle size for the safety assessment and environmental protection is important. Existing chemical nanoscale aluminum powder explosives and explosion in a confined space generated aerosol particle size spectrum and its changes over time for  2 way manifold  reports . Studies conducted in our laboratory showed that , despite the size spectrum with specific  Valve manifolds  vary, but nanoscale particle number concentrations are high. Agglomeration and sedimentation of collision and other reasons , the particle number concentration change with time approximately exponential decay law , " half-life " in the range of 30 ~ 90min . To avoid inhaling plutonium irradiation damage caused by  Stainless steel needle valve  plutonium experiments exhaust general subject of nuclear grade HEPA filter processing, in which plutonium concentrations below the national standard limit to emissions. Of radiation protection regulations , 239PuO2 derived air concentration 0.2Bq/m3. Currently, the widespread use of plutonium aerosol α continuous monitor for continuous online monitoring of plutonium aerosol , the principle is: membrane aerosol particles collected online , the emission of α particles with α detectors measure , according to the judgment particle energy spectrum nuclide composition and content .

The sampling device built experimental platform, the use of computer testing system, made ​​a lot of model validation experiments

In the preliminary design and manufacture of sampling device for the study, that the simulation platform, the establishment of the new sampling device simulation model. In order to verify the correctness of the simulation model, the authors of the sampling device built  Instrument valve manifolds  platform, the use of computer testing system, made ​​a lot of model validation experiments. Experimental results show that the authors constructed a  Valve manifold  model is correct, can be used as a basis for 2 way manifolds . Since the authenticity of systematic sampling of materials depends largely on the stability of the sampling rate of the car, so the author based on the simulation model, the process of reclaiming speed stability issues detailed study draws some important conclusions. Its main tasks are: Introduction to sampling system structure and working principle, a simulation model of the system, and using the model to analyze the sampling process speed load characteristics;

Sampling methods and working conditions, to study the factors that affect the accuracy of the sampling results

Material sampling equipment material detection system is the key equipment , which directly determines the accuracy of the sampling material test results are correct. Material sampling equipment varied, its sampling theory, sampling method, applications are also different . Therefore, according to the working principle of sampling equipment , sampling methods and working conditions, to study the factors that affect the accuracy of the sampling results , to ensure sampling distortion, it is particularly important. In this paper my school developed material  High pressure ball valve  system sampling device for the study, described in detail the working principle of this device and the working process , and according to its working principle and the field conditions of its structure , a detailed  Valve manifolds of the work process research to identify the key factors affecting the sampling results - system external load , its theoretical calculations and  Instrument manifold  verification, and proposed to reduce the system load impacts outside the program , developed during sampling of the best operating parameters , making the device the more reliable performance improvement. First, the author analyzes the sampling device work site conditions and requirements , introduced the device 's basic structure and working principle , that the only car in reclaiming the case of uniform operation to ensure sampling results are not distorted.

With the continuous development of industrial technology, samples of materials have become increasingly demanding

In the blast furnace industry, in order to ensure the quality and efficiency of iron, scientific, rational and efficient use of materials into the furnace, steel companies into the furnace for all materials needed for real-time particle size measurement, and particle  5 way manifolds  results are accurate or not the key technologies one is that the level of sampling accuracy. With the continuous development of industrial technology, samples of materials have become increasingly demanding. However, at  Valve manifolds  our country there are few specialized sampling equipment, most of the iron and steel enterprises are manual sampling, sample representativeness poor, which directly affect the iron product quality. In order to  2 way manifold  and economic efficiency of enterprises, iron and steel enterprises need according to their own choice and design requirements suitable sampling device.

Sample Cylinders Problems

Liquid ammonia (liquid anhydrous ammonia) is an important chemical products, chemical composition of NH3, mainly used in the manufacture of nitric acid, inorganic and organic chemical products, chemical fertilizers and frozen, metallurgy, medicine and other industrial raw materials, use very extensive. Ammonia is a toxic,  Valve manifolds  hazardous chemicals. Once the leak could result in liquid ammonia poisoning, suffocation, causing serious consequences, the lower the boiling point of liquid ammonia is -33.35 ℃, is a very unstable system, there is a strong  Instrument valve manifolds  easily in case of fire, mixed with air concentration reaches 15.5% 27.7% when the explosion occurred. Sample Cylinders problems because the low boiling point of liquid ammonia, highly volatile,  High pressure ball valve , explosive and other particularity sampling operation, must wear protective masks, gloves and other necessary protective antifreeze products, the technology for ammonia indicators when analyzing multi-sample cylinders used for sampling, sample cylinders, but there are a series of liquid ammonia to take security risks and negative factors.

In selected siphon tube diameter and quantities, generally flow control

When the channel or channels with channel intersects with the road, and the two drains or water channels at the same level  Instrument valve manifolds almost the height of the aqueduct inconvenient to use, you can set the siphon tube. Inverted siphon arrangement, its axis shall be the intersection of the river, ditch, road perpendicular to narrow the length of the building; their embedment depth, the tube should be below the top  2 way manifold  riverbed scouring lines of at least 0.5m, or below the channel bottom, roads road 1.0m. In selected siphon tube diameter and number, generally at a flow rate control. Flow rate is too large, head loss increases, channels available head relative decrease; taking into account through a small flow, the flow rate is too small will not occur due to siltation.

For the connection channel and pressure pipe laying

When the channels and rivers, valleys, roads or other channels intersect, for the connection channel and pressure pipe laying. When the intersection height is small, can be buried in the ground, the middle tube body supine, reclined or can be made before  High pressure ball valve  two shafts. Wider use of oblique horizontal; silo flow is not smooth, head loss, suitable for road intersects with the situation. When crossing a large valley height, can be laid in the ground slope, across the water partially  3 way manifolds or through the bridge. The import, export, transition section and tube body 3 parts. Large projects inlet section also sets overhaul tube body, dredging using retaining gates and trash rack and so on.

Conventional HVDC system normal control mode

With the increasing power transmission and conveying distance scale gradually lengthened, the existing level ± 500kV DC transmission will not be able to meet the requirements, the objective need to adopt a higher level of DC transmission voltage levels. According to the Southwest Water outgoing transmission planning programs of research and related research conclusions combination of foreign, ± 800kV DC  Stainless steel needle valve feasible, more suitable for China's actual situation. In the conventional HVDC system's normal control mode, the rectifier side of the DC power required to calculate the dc current command, according to the current measurement value and the current value of the deviation obtained by proportional integral part of the firing angle to control the DC current while the commutation  Valve manifolds  tap slow  Trunnion ball valve  the firing angle as the reference value in the range of ± 2.5 °. Inverter side using constant extinction angle control, constant DC voltage control method combining with rectifier side HVDC control system together constitute the basic closed-loop control. ± 800kV DC transmission uses two 12-pulse inverter in series wiring, this wiring to make it run way more diverse.

Full metal pole loops; complete monopolar ground return line running

With the growth of the national economy , energy and the distribution of the load center features make the ultra- long-range , large -capacity power transmission become inevitable , the use of ± 800kV HVDC transmission technology, not only conducive to  Valve manifolds  transmission of scale , saving a lot of resources, transmission corridor You can also increase the level of security and stability of the grid . HVDC (UHVDC) project generally use two 12-pulse valve means connected in series to form a pole, this structure makes the entire DC system has great flexibility , based HVDC (UHVDC) of a pole 2 the characteristics of a valve in series , the DC system operation modes: full bipolar operation ; complete monopole metal loops ;  Stainless steel needle valve  ground return line run ; 3/ 4 bipolar ( a very full 1/ 2 is extremely uneven ) run ; 1/ 2 bipolar operation ; 1/ 2 pole metal loop run ; 1/ 2 monopolar ground loop operation. For the above characteristics, HVDC project must meet the following requirements: ① tandem two manifolds can be run  Stainless steel needle valve  ; ② stable operation of the two valves in series should be essential to maintain symmetry operation ; ③ When either a valve operation, through relevant the control inputs of two manifolds, AC / DC system should not produce too much disturbance ;

Check valve function will increasingly diminish

To ensure the oil pump in the stationary state does not leak, the oil pump in the oil port at the installation of a check valve structure design. With the use of time and the oil pump check valve spring force continue to decline, coupled with the gradual  Instrument needle valve  body within the oil, check the function will become increasingly diminished, the engine does not work, there is still oil from the oil tank through its check valve slowly leaking into the carburetor float chamber. The design of the engine, pump valve leakage trace is allowed process, but there are certain limits. Once the leakage oversized, when the motorcycle  Valve manifolds  is too long, the oil pump check valve from leaking out of the oil will be overflowing carburetor float chamber, causing difficulty in starting the engine. Barely started, which emit large amounts of blue smoke muffler, leakage serious, and even cause the engine to fail to start.

The check valve in the normal drilling process are at the normally-on state

Including the BOP system , the check valve is actually a check valve connected between the drill collars and drill pipe . Normal drilling , the drilling fluid flows downwardly through the valve gap cycle ; when a kick or blowout occurs, the high pressure fluid flow in the reverse direction , to promote the spool piece with the base generated by the contact seal to prevent deterioration . Check valve with quick response and good sealing capacity , in the anti- kick , play a decisive role in the blowout on drilling safety plays an important guarantee. However, the check valve in the normal drilling process are often turned in , high-pressure  Instrument valve manifolds  erosion and corrosion , easy to cause valve seal failure or even completely scrapped, and the entire system within the blowout preventer , the well Dizhi return valve worst working conditions . Therefore it is  Check valve  for the check valve failure mechanisms in-depth research, analysis, in order to take  Male connector  to improve valve performance , and promote the overall level of non-return valve to a new level , which reflects its significant technical value and economic benefits. The need to study the drilling process , when faced with high-pressure formations , if there is no reliable blowout preventer system may occur . Whether drillstring outside blowout , or drill string blowout , there is the potential danger caused by catastrophic accidents , and some pretty heavy consequences .

Abnormally shut down valve, if close the program properly, it may cause water hammer due to off valve pipe rupture

With the development of urban construction and people's living standards improve, more and more long-distance water conveyance project. Long distance water conveyance and pump pressure of gravity in two ways, gravity water system does not require  Instrument valve manifolds  during normal operation is less than the hydrostatic head piezometric head, but when the pipeline gate valve is closed, the tube hydrostatic head is the largest terrain largest gap, the greater the gap, the higher the pressure pipe, when the gate valve is abnormally shut down, if the shutdown  Check valve , close the valve may cause water hammer pipe rupture, causing the drying up bridging the water hammer. Giant water hammer pressure often affects the normal operation of the pipeline and even devastating harm. So it brings water system's  Double ended cylinder  have attracted the attention of researchers home and abroad, so this study schedule for water safety significance. Gravity flow water for long distance pipeline water hammer protection systems research, there are a variety of domestic and international solutions and protective measures, including the valve as the most common pipe fittings.

Micro Slow Close Check Valve Water Hammer Systems Security

Micro Slow Close Check Valve Problems of protection against water hammer on Micro Slow Close Check Valve closure process carried out a detailed analysis by the method of characteristics for the example calculation reveals the potential problems this valve for micro- resistance slow closing check valve design and use to provide a reference . Micro Slow Close Check Valve Water Hammer system security one , in the pumping station , the pump outlet check valve is installed at a water  Valve manifolds  devices , its main role is in an accident when the pump stops to prevent the backflow of water and unit high-speed rewind. Since ordinary swing check valve partial resistance, are being replaced by other energy-saving valve , which ,  Valve manifolds  stop valve is an alternative device in one. At present , the domestic application of more northern areas is declining Swing Slow Close Check Valve , it is a good energy saving products , but its water hammer  High pressure ball valve  is not ideal , easy to cause water hammer accidents. In this paper, method of characteristics , examples of calculations from the analysis of its water hammer protection features, proposed the valve problems in the application of this valve precautions for analysis, for the valve unit is being used to provide technical reference ; Meanwhile, for micro Slow close Check Valve should have discussed the characteristics , in order to facilitate the design and operation management in the application of such valves to choose.

Hydraulic systems in nuclear power plants has been widely used in a variety of non-return valve

Nuclear energy is energy efficient in the world energy mix has occupied the position can not be ignored , so the safety of nuclear power plants has also been referred to the new height . Nuclear power plants are large and complex hydraulic system hydraulic control system , the system is strictly prohibited countercurrent many locations phenomenon , or it may lead to serious accidents, therefore , require a lot of system -return element . Fluid control valve is an important safety  Stainless steel needle valve  , it is through closing fluid countercurrent to ensure directional flow of fluid , which protects other fluid machinery and pipeline safety . Therefore, in the nuclear power plant hydraulic system has been widely used in a variety of non-return valve , such as swing check valves . Swing check valve has a disc-type plug hinged on the edge , through the back off.  Trunnion ball valve design , low price, good economy , high reliability, easy maintenance and daily wide range of sizes , etc., the valve in the nuclear energy systems are widely used , the impact of the piston slam shut valve overpressure has been generated as experimental measurements and models to study the subject . Thus, the conventional movement of the check valve member (i.e., the valve head or valve ) to do the speed often rapidly opening and closing movement , the valve itself which is necessary features .

Fluid control valve is an important safety element engineering

Nuclear energy is energy efficient in the world energy mix has occupied the position can not be ignored , so the safety of nuclear power plants has also been referred to the new height . Nuclear power plants are large and complex hydraulic system hydraulic control system , the system is strictly prohibited countercurrent many  Stainless steel needle valve  , or it may lead to serious accidents, therefore , require a lot of system -return element . Fluid control valve is an important safety component engineering , it is through closing fluid countercurrent to ensure directional flow of fluid , which protects other fluid machinery and pipeline safety . Therefore, in the nuclear power plant hydraulic system has been widely  Instrument needle valves  of non-return valve , such as swing check valves . Swing check valve has a disc-type plug hinged on the edge , through the back off. Because of its simple design , low price, good economy , high reliability, easy maintenance and daily wide range of sizes , etc., the valve in the nuclear Valve manifold  are widely used , the impact of the piston slam shut valve overpressure has been generated as experimental measurements and models to study the subject . Thus, the conventional movement of the check valve member (i.e., the valve head or valve ) to do the speed often rapidly opening and closing movement , the valve itself which is necessary features .

Study and optimize the technical parameters of the main valve has a very important significance

Since marine nuclear power plant a special structure of the loop, we must set the main valve in the loop to control the primary coolant flow direction. Because hedge check valve which has novel design principle, the characteristics of simple structure, so the circuit  High pressure ball valve  power plant a very broad application prospects. Hedge check valve of the performance indicators for the safety of nuclear reactors have a major impact, the study and optimize the technical parameters of the main valve has a very important significance. In previous studies, this paper, based on the prototype for hedge type check valve in the experiment  Instrument manifolds  flow will not shut off the problem of lax, the main check valve structure presents two improvements. The use of pre-processing software to establish the main valve geometry, meshing, CFD software to use these two structures were improved drag coefficient, flow characteristics and valve head the force of these three aspects of the analysis, and based on the numerical simulation results, completed a hedge check valve structure optimization, increasing the main valve in the closed valve when the hydraulic power to determine the conduct of hedge-type check valve stamping tube diameter increases and the use of these two activities in the seat structure improvements.

Valve controlled protection system with high reliability and long-running sexual

Axial fan to blast valve as research object, the check valve controlled protection system , aimed at the check valve itself does not affect the work of the case , in the blast when the normal flow of ventilation ducts , improve valve valves, reducing valve head loss , improve blast furnace steel production . Valve controlled  2 way manifold  parts protection system using electromagnets and three-phase AC motor as the driving force to enhance the valves, electric control part adopts PLC as the main control device to control the movement of the mechanical structure ;  Instrument manifold  ​​redundant monitoring module , to improve the system reliability ; prepared using the graphical programming software remote monitoring program to facilitate the operator to operate the control system and view historical data ; serial communication and the use of CAN bus technology to connect PLC  Instrument valve manifold , redundant monitoring module and a remote monitoring system. Valve controlled protection system with high reliability and long-running nature , and has expansion capability. The greatest feature of this system is the mechanical moving parts with our own security, which can be electrically controlled in the case of partial failure of the check valve can still ensure the work ; Meanwhile , PLC and redundant monitoring module via two communication systems simultaneously, improving reliability ; preparation RMON program good user interface , making the system easier for the operator to accept.

Butterfly cushion valve with automatic opening and self-closing feature

Butterfly cushion valve is general machinery products. Domestic production of butterfly cushion valve, the main structure of the same type and applies only in the sealing temperature differ. Butterfly cushion valve with automatic opening and self-closing  2 way manifolds  automatic valves, pressure loss also has shortcomings, is a traditional blast furnace  Instrument valve manifolds  supporting devices. In this paper, the technological transformation of check valves, check valves shall be  Trunnion ball valve  a control system, not only did not change the check valve automatically opens, auto-off function, but also it has the energy-saving features, while improving the prevention and control of non-return valve BF axial fan surge and counter functions....