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.