Liquid Ring Vacuum Pump In Ceramic Vacuum Filter

Liquid Ring Vacuum Pump In Ceramic Vacuum Filter

Precision ceramic vacuum filter integrates electromechanical, microporous ceramics and ultrasonic technology. It relies on the suction and capillary action of liquid ring vacuum pump to realize solid-liquid separation. It is widely used in mining, metallurgy, chemical industry, environmental protection and other industries.

Precision ceramic vacuum filter features:

۱٫ High vacuum (vacuum 0.09-0.098 MPa), low moisture filter cake.

۲٫ The solid content of filtrate is less than 50 ppm. It can be reused to reduce emissions.

۳٫ Compared with the traditional filter equipment, the energy consumption can be saved by more than 90%, the energy consumption is low and the operation cost is low.

۴٫ Compared with traditional ceramic filters, filter cake washing is added, which is suitable for washing materials.

۵٫ The use of PLC and computer combined with automatic valve control, high degree of automation, reduce labor intensity.

۶٫ Compact structure, small area, easy installation and maintenance. Liquid Ring Vacuum Pump in Ceramic Vacuum Filter

۷٫ The advanced drainage system can be used under any working conditions.

Precision Ceramic Vacuum Filter Principle :

Slurry suction zone: When working, the filter plate immersed in the slurry is combined with vacuum pressure under capillary action, and the surface is adsorbed into a layer of filter cake. The filtrate enters the distribution valve through the filter plate to the drainage tank.

Leaching area: After the filter cake is turned out of the slurry hopper, the filter cake is sprayed and washed.

Drying zone: The filter cake continues to dehydrate under the action of high vacuum force of water ring vacuum pump.

Discharging area: In the absence of vacuum, the scraper discharges automatically.

Backwashing: Industrial water or filtrate enters the ceramic plate through a distribution valve and is cleaned from inside to outside. Clean the blocked micropore. After a period of using the ceramic plate, the ceramic plate can be cleaned by the combination of ultrasonic wave and low concentration acid in order to keep the high efficiency of using the ceramic plate.

Effect diagram of ceramic filter:

Main components: filter board, main engine, air-water mixed constant pressure backwashing system, control system.

Liquid-Ring-Vacuum-Pump-in-Ceramic-Vacuum-Filterhttps://vacuumpumps.ir

liquid ring vacuum pump Application :

At present, liquid ring vacuum pump has been widely used in the dewatering of non-ferrous metals, rare metals, ferrous metals, non-metallic concentrates and tailings in mines, oxides, electrolytic slag, leaching slag, dewatering of slag and acid treatment of waste sewage sludge in chemical industry. Material fineness ranges from – ۲۰۰ to – ۴۵۰ meshes and various superfine materials.

کاربرد پمپ وکیوم در صنعت آجر،کاشی و سرامیک

کاربرد پمپ وکیوم در صنعت آجر،کاشی و سرامیک

پمپ خلا(وکیوم) برای صنعت آجر و سرامیک با بهبود مستمر سطح زندگی مردم ، نیازهای تزئینی افراد برای ساخت سرامیک نیز بیشتر و بیشتر می شود.

به خصوص سبک سنگ مرمر طبیعی را در مکان هایی مانند مبلمان منزل دوست دارند. با این حال ، اگر از سنگ مرمر و سایر مواد برای ساخت آجر استفاده شود ، مهم نیست که در استخراج مواد یا ساخت آجر ، منابع انسانی و مادی بیشتری مصرف می شود ، گران است. در همان زمان ، با توجه به رقابت شدید در بازار سرامیک ساخت و ساز ، به منظور گسترش سهم بازار ، تولید کنندگان سرمایه گذاری بیشتری در محصولات با تکنولوژی بالا (مانند کاشی های لعاب رنگ لعاب فعلی ، چاپ جوهر افشان و سایر محصولات ثانویه) انجام داده اند. پخت کاشی های کامپوزیت ریز بلورین) ضمن کاهش هزینه ها و افزایش طرح های محصول. فناوری این محصول نسبتاً بالغ است ، اما هزینه تولید هنوز زیاد است و محصول نهایی نمی تواند به سنگ سنگ یا اثر دست انداز برسد.

بنابراین ، چگونگی تولید نوعی کاشی و سرامیک با هزینه تولید کم و دستیابی به موفقیت انقلابی در بافت الگو ، مواد و فناوری تولید ، موضوع داغی در صنعت سرامیک سازی است. در تولید آجر ، کاشی های بام ، چینی و سرامیک های صنعتی ، علامت مهم کیفیت این است که هیچ محصول کاویتاسیون وجود ندارد. پس از شلیک ، سرامیک های حاوی چنین حفره هایی ممکن است در کوره ، در موارد شدید حتی کل دسته ، از بین بروند. در آجر ، این نقص کیفی معمولاً سالها طول می کشد تا ظاهر شود. در زمستان ، آب به منافذ سطح نفوذ کرده و آنها را می شکند. پمپ برای صنعت آجر و سرامیک خلا(وکیوم) جز component اصلی پردازش سرامیک است. به خصوص در میکسرها و اکسترودرها ، فناوری خلا می تواند ترکیبات رس دگاس را ایجاد کند ، بنابراین از بین بردن درگیری هوا در مرحله فشار / اکستروژن ، بنابراین محصولات قالب گیری تقریباً بدون منافذ را تضمین می کند. این همچنین پایداری ابعادی آنها را بسیار بهبود می بخشد ، از تغییر شکل قبل از خشک شدن جلوگیری می کند و از دقت ابعاد محصول نهایی اطمینان می یابد. پس از بارگیری خشت آجر در اکسترودر ، از خلا برای حذف هوا استفاده می شود ، بنابراین از ایجاد حفره و ترک خوردگی بعدی جلوگیری می کند. خاک رس سرامیکی مشابه خشت آجری ابتدا در مخلوط کن قرار داده می شود و تحت فشار آب یا بخار قرار می گیرد تا مخلوط یکنواختی ایجاد شود. سپس به اکسترودر منتقل شده و تحت فشار زیاد به داخل قالب فشار داده می شود. سپس مواد به طول مناسب اکسترود شده ، خشک و شلیک می شوند. ذوب خلا(وکیوم) ، صنعت تولید آجر ، سرامیک صنعت خلا(وکیوم) برای متالورژی ، صنعت آجر و سرامیک بخش بسیار مهمی است. می تواند برای جلوگیری از اکسید شدن فلز به دلیل دمای بالا در حین فرآوری استفاده شود. آب و هوای موجود در آجرها و سرامیک ها با خلا(وکیوم) تخلیه می شود تا از کیفیت آنها اطمینان حاصل شود. محصولات قابل استفاده: سری پمپ خلا valve سوپاپ کشویی ، سری پمپ خلا(وکیوم) چرخشی ، واحد خلا unit ، سری پمپ خلا(وکیوم) حلقه آب. پمپ خلا(وکیوم) پره روتاری روغن کاری شده در چنین کاربردهایی مورد استفاده قرار گرفته است. اکنون ، سیستم جدید گاززدایی از خاک رس معرفی شده است که با همکاری نزدیک با کارخانه آجر طراحی شده است. جز core اصلی سیستم خلا(وکیوم) ، پمپ خلا(وکیوم) پره ای دوار خشک است. هوا و بخار آبی که بدون روغن و آب می گیرد را فشرده می کند. این سیستم به سیستم فیلتر ، خنک کننده آب و کنترل ، با دو اندازه مجهز شده است.

vacuum pump For Brick And Ceramic Industry

vacuum pump For Brick And Ceramic Industry

With the continuous improvement of people’s living standards, people’s decorative requirements for building ceramics are also getting higher and higher. People especially like the style of natural marble stone in places such as home furnishing. However, if marble and other materials are used to make bricks for laying, no matter in material mining or brick manufacturing, more human and material resources are consumed , expensive.

At the same time, due to the increasingly fierce competition in the construction ceramic market, in order to expand market share, manufacturers have invested more in high-tech products (such as the current underglaze color glazed tiles, ink-jet printing and other secondary firing microcrystalline composite tiles) while reducing costs and increasing product designs. The technology of this product is relatively mature, but the production cost is still high, and the finished product can not reach To stone texture or bump effect. Therefore, how to produce a kind of ceramic tile with low production cost and revolutionary breakthrough in pattern texture, material and production technology is a hot issue in the construction ceramics industry.

In the production of bricks, roofing tiles, porcelain and industrial ceramics, the important sign of quality is that there is no cavitation products. After firing, ceramics containing such cavities may be destroyed in the kiln, in extreme cases even the entire batch. In bricks, this quality defect usually takes years to appear; in winter, water seeps into the pores of the surface and breaks them.

pump-for-brick-and-ceramic-industry

Vacuum is the main component of ceramic processing. Especially in mixers and extruders, vacuum technology can Degas clay compounds, thus eliminating air inclusions in the pressing / extrusion stage, thus ensuring the molding products with almost no pores. This also greatly improves their dimensional stability, avoids the deformation before drying, and ensures the accurate dimensional accuracy of the finished product.

After loading the brick clay into the extruder, the vacuum is used to remove the air, thus preventing cavitation and subsequent brick cracking. Similar to brick clay, ceramic clay is first put into the mixer and pressurized with water or steam to form a uniform mixture. It is then transferred to the extruder and pressed into the die under high pressure. The material is then extruded to a suitable length, dried and fired.

Vacuum smelting, brick, ceramic manufacturing industry vacuum technology for metallurgy, brick and ceramic industry is a very important part. It can be used to prevent metal from being oxidized due to high temperature during processing. The water and air in the bricks and ceramics are evacuated by vacuum to ensure the quality they have.

Applicable products: slide valve vacuum pump series, rotary vane vacuum pump series, vacuum unit, water ring vacuum pump series.

Oil lubricated rotary vane vacuum pump has been put into use in such applications. Now, a new clay degassing system named is introduced, which is designed in close cooperation with the brick factory. The core component of the vacuum system is a dry rotary vane vacuum pump. It compresses the air and water vapor it takes in without oil or water. The system is equipped with filter, water cooling and control system, with two sizes.

Vacuum Systems

Presentation on theme: “Modern Devices: Chapter 4 – Vacuum Systems”— Presentation transcript:

۱ Modern Devices: Chapter 4 – Vacuum Systems
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Chapter 4 – Vacuum SystemsEnabling High-Tech IndustriesModern Devices:The Simple Physics of Sophisticated TechnologybyCharles L. Joseph and Santiago Bernal

۲ Vacuum Chamber Technology
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Fig. 4.1 A large floor-standing vacuum chamber. At the left is an ion vacuum gauge (top) and valve with rubber hose to roughing pump (bottom). Numerous access ports (electrical feedthroughs, window ports, and blanks) are shown on the circumference. A cryopump is shown attached underneath chamber.Vacuum technology is needed for a wide variety of advanced instrumentation and manufacturing methods. Creating a vacuum is simply a matter of pumping the gasses out of a sealed container, known as a chamber or tank. Ultimately, the achievable level of vacuum is set by the pumping speed compared to the residual leak rate.Vacuum chambers come in all shapes and sizes. Most have various ports to feedthrough electrical signals or to manipulate mechanically items inside the chamber.Vacuum Chamber Technology

۳ Operating ranges of pumps and gauges
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Figure 4.2 The normal operating ranges of various type of pumps (red) and gauges (blue). The three classifications of vacuum are shown at the top.Operating ranges of pumps and gaugesUHVHigh Vac.Rough VacuumVenturi PumpMechanical PumpSorption PumpThermocouple GaugeDiffusion PumpTurbomolecularCryopumpIon PumpUHV Ion Gauge (hot filament)Pressure (Torr)

۴ Vacuum Chamber Technology
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Fig. 4.3 Cross-sectional diagrams of the two type of vacuum sealing mechanisms. The sealing surfaces as depicted are on the top and bottom surfaces. The groove must be wide enough to allow the O-ring to deform, making a seal. For a gasket, the harder knife-edge flange cuts a sealing grove into the softer gasket material.Hallow tube to establish a sealed volume between vacuum componentsASA-style sealTop and bottom O-ring vacuum sealing pointsConflat SealSeal by cutting intocopper gasketThere are two basic types of seals used for connecting two vacuum tank pieces together: 1) rubber or Viton O-rings pinched between two metal surfaces and 2) copper or silver-plated copper gaskets sandwiched between two surfaces with hard knife edges. Ultrahigh vacuums (UHV) can only be achieved with metal gasket seals. UHV chambers that do have O-rings, those portions are isolated from the main chamber via a UHV valve.Vacuum Chamber Technology

۵ Vacuum Chamber Technology
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Figure 4.4 An assortment of O-rings and copper gaskets along with a flanges. One feedthrough flange with three electrical connectors is shown at top center.Vacuum Chamber TechnologyThere are several standard configurations for O-rings and gaskets, as well as a number of vacuum quick-connection flange systems. For simplicity, the ASA O-ring and the CF Conflat gasket systems are shown in several sizes.O-rings can be reused many times, but copper gaskets are generally used only once. Copper gaskets, however, remain excellent seals for years if undisturbed.

۶ Physics of some vacuum gauges
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Thermocouple JunctionHeatedFilamentHallow Pipe toVacuum ChamberElectricalContactsi2 i1Physics of some vacuum gaugesThe physics behind a TC can be understood in terms of the responses of various metal alloys to temperature. When two ends of a wire are held at two different temperatures, a small voltage potential of a few millivolt (mV) is observed between the two ends. If two wires of different alloys are subjected to the same temperature disparity, one will have a slightly higher voltage than the other. A thermocouple junction is created if the two ends are connected together and share a common DT.This device is transformed into a vacuum pressure measurement by continually adding a fixed amount of heat via the filament. The amount of residual gas in the chamber impacts the amount of convective cooling and in turn, determines the equilibrium temperature at the TC junction end. The net current flowing through the TC measures the pressure.A thermocouple (TC) gauge is perhaps the most widely used since its operating range starts at the limits of mechanical vacuum gauges and ends at the crossover pressures for starting most HV or UHV pumps.Figure 4.5 The anatomy of a thermocouple (TC) gauge. The interior volume of the gauge has the same vacuum as the chamber, usually being connected through a hallow pipe (right) with a threaded end. The resistance of the TC is set by rate of cooling, which is proportional to the amount of residual gas.

۷ Physics of some vacuum gauges
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Ion collectorThermionicEmissionFilamentHallow metaltube to vacuumGlassTubeGridFigure 4.6 A hot cathode ion gage functions by passing a current and resulting voltage drop through a resistive material that heats up, emitting electrons into the vacuum. A series of rings connected to the positive volt side of the DC voltage, accelerating the free electrons towards the center. While these rings collect some electrons, many pass through, ionizing the residual gas. The current between the ion collector and the grid is proportional to the residual pressure.Physics of some vacuum gaugesThe UHV sensor of choice is the hot cathode ion gauge. The voltage across the resistive hot filament is typically 30 Vdc and generates a 10 mA (0.01 Amps) current of thermionic free electrons. These free electrons are attracted towards the grid, which biased at approximately +150 to +200 Vdc.While hot cathode ionization gauges have linear response over 10-4 to torr, all ion-gauge measurements are seriously affected by gas composition. For example, He gas only produces of the signal that N2 gas does,

۸ via venturi, mechanical, or sorption pumps
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.mufflerFigure 4.7 In a venturi pump, a gas flows through a restriction, causing the pressure to drop. An opening (bottom) pulls air from the volume to be evacuated. Only low-quality, rough vacuums can be established with this device.Low vacuumvia venturi, mechanical, or sorption pumps

۹ via venturi, mechanical, or sorption pumps
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Right Sorption Pump without Styrofoam sleeveLeft Sorption PumpStyrofoam sleeve tohold liquid nitrogenValveVenturiPumpThermocouple& gaugeMetalHoseFigure 4.8 A pair of sorption pumps along with supporting equipment is shown. These pumps function by cooling the residual gas from the chamber to the point where it condenses to liquid form. The pictured pump station has valves so one or both sorption pumps can be used and gauges to measure two stages of vacuum.Low vacuumvia venturi, mechanical, or sorption pumpsPumps are classified into two types: gas transfer and gas capture. A sorption pump is a gas capture type. It pulls a vacuum by trapping and condensing most gases into the liquid phase. Eventually, gas capture pumps become full, must be taken off line, and heated to drive out the captured gas.

۱۰ via diffusion, turbomolecular, or cryogenic pumps
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Oil reservoirTo roughingPumpSeparateLN2 TrapVacuum ChamberExteriorflow ofcoolingwaterHeating elementFigure 4.9 A schematic representation of a molecular diffusion pump is shown. A heating element causes a special oil of large, complex molecules to boil, sending small amounts of oil upward as depicted by the gray arrows. The oil strikes deflectors and is gravitationally pulled back towards the oil reservoir, dragging residual gas molecules down to the lower portion of the pump. A roughing pump continuously removes the slightly over-pressurized gas caused by the oil flow.High Vacuum (HV)via diffusion, turbomolecular, or cryogenic pumpsIn contrast to the gas-capture sorption pump, the molecular diffusion pump is a gas transfer type. A foreline pump must first be used to achieve a vacuum at or below the crossover point. Then the chamber can be opened to the diffusion pump, but the foreline pump must be used a second time to remove the transferred exhaust from this main pump.

۱۱ via diffusion, turbomolecular, or cryogenic pumps
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Venturi  ۸K He15 K cold vanes to trap N2, O2CompressorPressurizedHe gas inputHe gas return80K cold head to trap H2OReflective, 80K ShieldFigure 4.10 A cryogenic pump operates by dramatically changing the pressure of He gas at two points in the cycle. The sudden drop in the He pressure causes it to go from approximately room temperature to about 10 degrees above absolute zero. The helium is connected to a series of vanes, which become sufficiently cold to freeze the residual gas from the vacuum chamber.High Vacuum (HV)via diffusion, turbomolecular, or cryogenic pumpsA Cryopump is an oil-free high-vacuum pump of the gas capture type. Cryopumps, properly known as cryogenic pumps, are similar to sorption (cryosorption) pumps, except portions of the pump are substantially colder. The basic physics behind the cryopump is to create an ultimate refrigerator and attach a cold finger to a series of progressively larger cold surfaces. The primary requisite is to get various surfaces sufficiently cold that various gas constituents are frozen or adsorbed onto one of several surfaces and held there for extended periods. It normally takes about 2 hours before a cryopump gets down to operating temperatures. These pumps require extensive roughing to vacuum pressures of ~50 microns (~5 x 10-2 torr) on the pump itself prior to turning on the compressor.

۱۲ Ultrahigh Vacuum (UHV)
Modern Devices: The Simple Physics of Sophisticated TechnologyCopyright © John Wiley and Sons, Inc.Figure 4.11 Ion pumps produce strong internal electrical fields, which accelerate the electrons and positively charged molecules. Many of these charges strike titanium or titanium and tantalum plates releasing a few Ti or Ta atoms, which chemically bond with gas molecules and then become adsorbed onto the interior walls of the pump in a process known as gettering. The sequence of events also produces more ions, which continue the pumping process.Ultrahigh Vacuum (UHV)via ion pumpsIon pumps are the best choice for UHV chambers, since these pull the hardest vacuums, as well as are clean, vibration free, and can be baked. Ion pumps also have low power consumption and long operating lifetimes despite being a gas capture type pump.

OIL-SEALED PUMPS AND BACKSTREAMING

OIL-SEALED PUMPS AND BACKSTREAMING

The vacuum industry has recently seen a major shift from oil-sealed mechanical pumps for roughing and backing applications to oil-free pumps of various types. Oil-free pumping continues to penetrate more and more applications and industries. Why the shift? Well, oil-sealed pumps contain oil and that oil can contaminate a process or product. It’s that simple, but at some point, it becomes necessary to evaluate the necessity of making the oil vs. oil-free decision. The applications of roughing pumps are so wide-ranging and diverse that it’s virtually impossible to make any categorical judgments. Each application, then, requires that a specific analysis and judgment be made, and these require an understanding of the sources of possible pump oil contamination along with the mechanism of oil transfer from a pump to a process.

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First, though, there are a number of ancillary considerations that might have an impact on an oil-free vs. oil-sealed decision. Oil-sealed pumps are extremely reliable. They have been built and improved for decades, and they require little periodic maintenance except for oil changes. Kits are available to rebuild pumps that have become damaged or to replace worn parts. The flip side is that used oil is regarded in most areas as toxic waste, which makes it difficult and expensive to get rid of. It’s also messy and potentially dangerous, as anyone who’s slipped on spilled oil can attest. Barring these considerations, it’s the possibility of contamination that’s the most common decision driver.

VAPOR-STATE TRANSFER

In applications where the oil-sealed roughing pump is plumbed directly to the chamber, direct vapor-state transfer from the pump to the chamber is the major source of oil contamination. If in doubt as to whether oil vapor contamination is occurring in a given system, place a drop of water on an inner surface of the chamber to see if it wets or beads. This is a very sensitive test, since the condensed oil will spread in a film a monolayer thick over the entire inner surface.

This means that liquid oil will cover all surfaces and not be localized to a particular area, say near the roughing line. When a pump operates continually, the oil within the pump will become hotter and hotter, due to simple mechanical energy heat transfer, until some maximumtemperature is achieved. The increase in oil temperature will result in an increase in oil vapor pressure since the vapor pressure is a function of temperature.

During the first part of a pumpdown cycle where viscous flow conditions obtain, little oil vapor transfer will occur due to the continual impacts of oil vapor molecules with air molecules. Backstreaming oil vapor molecules will lose their energy upon impact and be swept back into the pump through entrapment.

Once the pressure falls into the molecular flow regime, however, these impacts cease and oil vapor transfer begins to occur at a rate governed by the vapor pressure of the oil at whatever temperature the oil has reached. The effective vapor pressure of the oil is usually a function of its quality. Undistilled or poorly distilled oil will contain light fractions (low boiling point components) which will volatilize at low temperatures.

A simple practical test is to sniff the inlet of a hot pump. If a fishy odor is detected, the oil is undistilled or of poor quality. High quality, vacuum-distilled oil will be either odor-free or close to it. Obviously, using a high quality oil will provide lower backstreaming rates. Check the manufacturer’s vapor pressure specs at elevated temperature, not at room temperature. Some hydrocarbon, high lubricity, diffusion pump oils make excellent mechanical pump fluids with low(er) backstreaming rates.

Additional problems in vapor-state transfer occur due to extremely high temperatures that arise in the oil film sealing the rotating vanes to the pump cavity. These high temperatures are caused by mechanical friction at these points, and they can be high enough to cause chemical breakdown of the oil to the point where light fractions, which backstream easily, are broken from the hydrocarbon chains.

The effects of temperature on the pump’s oil vapor and resultant backstreaming rate should be considered in light of the fact that the backstreaming occurs constantly as long as the pump is operating in the molecular flow regime. This really means that hydrocarbon contamination is being continuously fed into the chamber.

NON-VAPOR PRESSURE TRANSFER

Transfer of liquids from the pump’s inlet into the pumping line can occur due to several mechanisms. The simplest occurs whenever the pumping line stays under vacuum when the pump is shut off or as the result of apower failure. Pressure from gases trapped within the pump or even through the pump from atmosphere literally forces some of the pump oil into the pumping line. This effect is often called suckback. Many pumps have a built-in valve or metering system to reduce this effect, but it can still happen and once is enough. In practice, an automatic vent valve should be included in the pumping line to vent the inlet line when the pump shuts off.

Additional liquid/vapor backstreaming occurs due to droplets of hot oil that can be physically flung from the pump’s inlet during operation due to mechanical breakdown of the oil films sealing the vane/body interface.

A slightly similar effect occurs when microbubbles of oil break on the surface. This is most often caused by either the expansion of trapped light gases such as helium or from the almost explosive expansion of condensed gases, such as liquid water which can be converted into steam. When the bubble expands and breaks, the surface tension is such that the bubble explosively breaks down and imparts sufficient energy to the oil to allow it to leave the pump either as liquid or vapor.

An important transfer mechanism is surface creep. Oil, released into the pumping line will tend to spread along any surface and finally migrate into the process chamber. Although the migration rate is low, it is a continuous effect and will finally reach the chamber. When the pumping line is at viscous flow pressures, little or no surface creep will occur due to continual impacts with the gases being pumped from the chamber. At lower, molecular flow pressures, the possible impacts with surface oil are too few to stop its motion along the pumping line toward or into the chamber.

 VACUUM PUMP TRAPS

There are a number of backstreaming traps commercially available. They are all effective to some extent, but they require careful handling and maintenance to ensure that, during cleaning or regeneration to remove trapped oil, that the oil is not allowed to escape into the upstream side of the trap. Many traps are regenerated by heating while being pumped on, and this procedure would easily allow the oil vapor to leave the trap from both the inlet and outlet ports.

Additionally, most traps have a room temperature surface path through them that allows surface creep to pass slowly through them. Although they can be effective, they can also lead to a fool’s paradise if it assumed that their installation will solve backstreaming problems.

PRACTICAL CONSIDERATIONS

Although oil vapor transfer through backstreaming is a potential problem for many processes, it is useful to examine the actual effects in light of the process to determine whether or not the potential problem can be dealt with or simply lived with. In many cases, it is possible to confine the use of a mechanical pump to viscous flow and then valve or shut it off when not in use to severely limit backstreaming. If the risk to the process is too great to take the chance, it is possible to switch to one of the many oil-free pumps now on the market and sidestep the problem entirely.

vacuum leak detector

vacuum leak detector

۱٫ How does the Prowler sensor work?

As refrigerant gas enters the sensor, a tiny chemical reaction occurs that results in an electrical change inside the sensor element. This change (which is completely reversible and not depleting) is then detected by a microprocessor (computer chip) that translates the chemical reaction into an alarm signal.

۲٫ How does the Prowler sensor compare to heated sensor leak detectors?

Besides having superior sensitivity, especially to the newer HFC refrigerants, the Prowler sensor also operates at a lower temperature than heated sensors. This is an advantage because it draws less current and doesn’t require the use of rechargeable batteries. Another advantage is that it can be used safely in combustible atmospheres.

۳٫ What happens when the Prowler detects that a leak is present?

When refrigerant gas enters the sensor, the Prowler detection circuit initiates three indicators that show a leak is present. The user hears an audio alarm (when not manually muted), feels a vibration in the handle, and sees the bar graph line(s) appearing on the LCD screen. Both the audio and vibration alarm are constant no matter how large the concentration of the gas. The LCD bar graph changes depending on the concentration of the gas in the sensor. The bar graph is also independent from the sensitivity level selected.

۴٫ How does the Prowler work so that the source of the leak can be located?

Unlike other leak detectors, the Prowler incorporates several innovative high technology features that allow the user to find the source of the leak without requiring any manual adjustments. Advanced computer software constantly monitors the surroundings for the presence of refrigerant gas. The detector then automatically calibrates itself so that it alarms only when it senses an increase in the level of refrigerant as the source of the leak is approached. The proprietary software then “filters” out and virtually eliminates any unwanted (false) alarm signals that occur away from the leak source.

 ۵٫ Will the Prowler detect large leaks without any manual adjustments?

Yes. However, if the Prowler alarms initially close to a large leak and then stops alarming before the source of the leak can be pin pointed, it means that the concentration of refrigerant in the area near the leak is similar to the concentration at the leak source. In this situation, it is important to move the sensor away from the leak source (usually above the suspected leak source) for 5 to 10 seconds to allow the sensor to self calibrate to a lower concentration before searching the area a second time. The detector will then alarm again closer to (or at) the source of the leak. Holding the probe away in this manner will also give a more accurate indication of the leak size on the bar graph.

۶٫ Will the Prowler alarm when entering a work area contaminated with refrigerant?

Yes. Nevertheless, you must always turn on the Prowler outside of the work area (in clean air) and allow it to complete the warm up cycle before entering an area where a large leak is suspected. The Prowler will alarm initially but will automatically self calibrate to the surroundings and will not alarm again until a larger concentration closer to the source of the leak is detected.

۷٫  Why does the alarm stop sounding when the sensor is held static at a leak source?

This is normal and demonstrates how the detector automatically resets (self calibrates) itself to the ambient. Once the Prowler alarms near the area of the leak, it should be moved away from the leak and back again to verify the exact location and size of the leak. If the leak is large (more than five bars), it may be necessary to move the sensor away from the leak area for 5 to 10 seconds.

۸٫  Can the Prowler determine the size of the leak?

Yes, once the leak has been pin pointed the maximum number of bars on the LCD screen will give the user an idea of the size of the leak. If the leak is large, (5 bars or more) it may be necessary to hold the detector away from the leak for 5 to 10 seconds in order for the circuit to reset completely and to give an accurate indication of the leak size.

 ۹٫  What does the Prowler do when it is turned on and is going through the warm up mode?

When turned on, the Prowler begins to energize and condition the sensor for use.  During this period, the unit will beep at a slow rate and the LCD bar graph will display the conditioning progress by gradually increasing.  Warm up is complete when all 10 bars are shown on the display. The beep rate will also increase and the sensitivity level will default to Medium.  NOTE: The bars on the bar graph may increase up initially and then down again before increasing to 10 full bars – this is normal.

۱۰٫ How should the Prowler be tested to make sure it is working properly prior to leak searching?

The preferred method to test the Prowler is with the Leak Test Vial that is included with the leak detector.  Although the Vial does not contain refrigerant gas or liquid (this is prohibited), the media in the Vial accurately simulates a small to medium refrigerant gas leak.  To test with the Vial, power on the Prowler by depressing the on/off button, allow the instrument time (up to 20 seconds) to energize the sensor, remove the plastic label seal on the top of the Leak Test Vial, and place the sensor closer to the small hole in the top of the Vile.  The beep rate should increase and the Leak Size Bar Graph should display a minimum of three bars.  The detector will calibrate itself to the Leak Test Vial if the sensor is held static close to the hole in the cap and will not alarm again until it is moved away and allowed to reset.  Consecutive testing at the cap and moving away from Vial will eventually result in the detector calibrating itself to the Vial.  In this case, the Prowler may require additional time away from the Vial in order to reset before it will alarm again at the Leak Vial.  Never use the Leak Test Vial with the cap removed from the bottle. NOTE: If the detector has been out of use for weeks, it may be necessary to set the sensitivity level to HI initially when testing the Prowler with the Leak Test Vial.

۱۱٫ Is there a way to test the Prowler with Refrigerant Gas before leak checking:

If it is necessary to test the Prowler with refrigerant gas, a small leak can be simulated by removing a Schrader valve cap on an access port of an HVAC system and waiting a few minutes for the accumulated gas to escape. Cracking open and quickly closing the valve on a cylinder of refrigerant is another option; however, the area around the valve should be fanned to allow the gas to dissipate before testing with the Prowler. This test method is not advisable because it is difficult to control the amount of gas emitted from a refrigerant cylinder. Opening and closing the valve on a cylinder typically emits a large volume of refrigerant, which is not representative of an actual leak in an HVAC system. If the Prowler is tested this way, the procedure for finding large leaks (see above) should be followed. If the procedure for finding large leaks is not followed, the automatic calibration feature of the Prowler may cause it to appear to be insensitive.

۱۲٫ Will the Prowler sensor become damaged if it is exposed to a heavy stream of gas coming from the valve of a refrigerant cylinder?

No. However, exposing the sensor to a heavy stream of refrigerant will cause the sensor to “saturate” and it may take up to 15 or more seconds for the sensor to automatically calibrate and reset to its maximum sensitivity level. For this reason, using a refrigerant cylinder is not an advisable means to test the sensitivity of the Prowler to any particular refrigerant.

۱۳٫ How can you claim the sensor will last up to 10 years?

The Prowler utilizes sensor technology that is based on room monitoring where sensors are required to be functioning continuously for years. Sensors used for this purpose cannot be depleted when contaminated with refrigerant or require any adjustment to operate at peak performance after running continuously for long periods. By converting continuous use into daily use, for a typical HVAC technician, it was determined using controlled test methods that the sensor would last more than 10 years (under ideal conditions). The sensor life test data was derived after testing the Prowler sensors continuously over a period of time.

question for vacuum pump and vacuum gauge

question for vacuum pump and vacuum gauge

۱٫ I don’t have a micron gauge so I leave the pump on the system for two to four hours, is this enough?

You can’t tell for sure. Without a micron gauge we do not know if the oil in the pump is clean. The oil in a vacuum pump acts as a blotter and absorbs all of the moisture and sediment in the system. As the oil becomes saturated, the efficiency of the pump is drastically reduced.


۲٫ If I put new oil in now and run the pump the same period of time, am I safe?

Oil should be changed after every job and should only be changed when the oil is still hot. As the oil cools, the moisture separates from the oil and clings to the metal of the pump. Therefore, when changing the oil and not checking it with a micron gauge, you’re still guessing as to whether the pump can actually pull the proper vacuum to eliminate the moisture in the system.


۳٫ I pull only from one side of the system using a micron gauge, but at times my gauge will jump up to a higher number. Is this right?

This can happen even if you pull on both sides of the system because there is a metering device to measure the pressure and refrigerant in the system. Air or moisture can be trapped in one side of the system and will eventually let go and therefore a higher reading on the micron gauge will occur. Sometimes moisture can be trapped in the oil of the compressor and when it escapes it will show up in the gauge.


۴٫ I purchased a new micron gauge. How low of a vacuum should I pull?

Some manufacturers have a micron range that they want their system pulled down to, so therefore, JB can only suggest a micron reading. Our suggestion is to pull a system down to 250-300 microns only if you are also pulling a vacuum on the compressor. Going below 250 microns, you will start degassing the oil in the compressor and it will not be the same lubricating oil as it was originally. The oil will only degass and will not suck up into the vacuum pump.


۵٫ It seems to take forever to pull down the system I am working on. Does this mean I have a leak or a lot of moisture in the unit?

Assuming that you are pulling on the high and low side of the system, did you remove the access valve cores? Leaving the cores in creates a big restriction and causes your vaccum to take a longer time to evacuate.


۶٫ I bought a new micron gauge and I wanted to try it out with just my vacuum pump. I attached the gauge directly to the pump and it immediately went down. I then closed my blank off valve on my pump and the gauge went up very rapidly. Is the valve on my pump leaking?

No. The gauge is too close to the pump and it does not have a chance to equalize in pressure. To do this experiment correctly, connect your pump and a micron gauge to a small tank with only copper tubing or JB`s DV-29. Close the blank off valve as you did before and you will see a big difference in the reading.


۷٫ You said with copper tubing, why not charging hoses?

Either copper tubing or metal hoses used in JB`s DV-29 are the only ways you can hold vacuum. Vacuum is critical for leaks, more so than refrigerant. Charging hoses, including environmental hoses, still permeate. Beyond permeation, where the hose ferrule is crimped to the hose, represents a potential leak under vacuum. Quick couplers with gaskets are not a good seal. When you screw down the male flare to the gasket quick coupler, the gasket goes into several contortions and will not seal properly. JB uses O-rings on our quick couplers and as you screw down the male flare you get a metal-to-metal seat and the O-ring lays around the flare to give it a perfect seal.


۸٫ Then this means I cannot pull a vacuum on my system unless I use metal hose or copper tubing?

No. You can pull a vacuum with charging hoses, but when you want to blank off the system to check for leaks, you will need to use copper tubing or metal hoses.


۹٫ I put my gauge connection to the pump when I am pulling a vacuum on a system, is this correct?

Many technicians do this for ease of hook-up, but remember with this set up you are actually reading what the pump is doing and not what the pump is doing to the system. To prove this theory, take a 50 foot coil of 1/4″ OD copper tubing, braze a flare on one end and a tee on the other. Attach a micron gauge to the male flare end, a gauge to the tee end, and a line from the tee to the pump. Turn the pump on and you will notice the side closest to the pump will be a lot lower than the other. Eventually, this will equalize out and give the same reading. This will occur in a system on which you are pulling a vacuum.

اهمیت گیج وکیوم در سیستم خلاء

۱٫ من میکرومتر ندارم بنابراین دو تا چهار ساعت پمپ را روی سیستم می گذارم ، آیا این کافی است؟

به طور قطع نمی توانید بگویید. بدون اندازه گیری میکرون نمی دانیم که روغن موجود در پمپ تمیز است یا خیر. روغن موجود در پمپ خلا به عنوان یک بلاتور عمل می کند و تمام رطوبت و رسوبات موجود در سیستم را به خود جذب می کند. با اشباع شدن روغن ، بازده پمپ به شدت کاهش می یابد.

۲٫ اگر الان روغن جدیدی بگذارم و در همان مدت زمان پمپ را کار کنم ، آیا من ایمن هستم؟

روغن باید بعد از هر کار تعویض شود و فقط در زمانی که روغن داغ است باید تعویض شود. با خنک شدن روغن ، رطوبت از روغن جدا شده و به فلز پمپ می چسبد. بنابراین ، هنگام تعویض روغن و بررسی نکردن آن با اندازه گیری میکرون ، هنوز حدس می زنید که آیا پمپ در واقع می تواند خلا proper مناسب را برای از بین بردن رطوبت در سیستم بکشد.

۳٫ من فقط از یک طرف سیستم با استفاده از یک میکرون سنج می کشم ، اما در بعضی مواقع سنج من به یک عدد بالاتر می رود. آیا این درست است؟

این امر حتی اگر دو طرف سیستم را بکشید ممکن است اتفاق بیفتد زیرا دستگاه اندازه گیری فشار و مبرد در سیستم وجود دارد. هوا یا رطوبت می تواند در یک طرف سیستم گیر بیفتد و در نهایت رها می شود و بنابراین میزان بیشتری از اندازه گیری میکرون اندازه گیری می شود. گاهی اوقات رطوبت می تواند در روغن کمپرسور محبوس شود و هنگام فرار از آن ، در سنج نشان داده می شود.

۴- من یک میکرون سنج جدید خریداری کردم. چقدر خلا باید بکشم؟

برخی از تولیدکنندگان محدوده میکرونی دارند که می خواهند سیستم آنها پایین بیاید ، بنابراین ، JB فقط می تواند خواندن میکرون را پیشنهاد کند. پیشنهاد ما این است که تنها در صورت کشیدن خلا on روی کمپرسور ، یک سیستم را به ۲۵۰-۳۰۰ میکرون کاهش دهید. با پایین رفتن از ۲۵۰ میکرون ، گاز زدایی روغن کمپرسور را شروع خواهید کرد و همان روغن روانکاری اولیه نخواهد بود. روغن فقط گاززدایی می کند و به پمپ خلا نمی خورد.

۵- به نظر می رسد که کشیدن سیستمی که روی آن کار می کنم برای همیشه لازم است. آیا این به معنی نشت یا رطوبت زیاد در واحد است؟

با این فرض که در سمت بالا و پایین سیستم می کشید ، آیا هسته شیرهای دسترسی را برداشته اید؟ با گذاشتن هسته ها محدودیت بزرگی ایجاد می شود و باعث می شود مدت بیشتری واکسن شما تخلیه شود.

۶٫ من یک میکرون سنج جدید خریداری کردم و می خواستم آن را فقط با پمپ خلا my امتحان کنم. من سنج را مستقیم به پمپ وصل کردم و بلافاصله پایین رفت. سپس شیر خالی خالی را روی پمپم بستم و سرعت آن بسیار سریع بالا رفت. آیا شیر پمپ من نشت می کند؟

نه. اندازه گیری بسیار نزدیک به پمپ است و فرصتی برای برابر شدن فشار ندارد. برای انجام صحیح این آزمایش ، پمپ و میکرومتر خود را به یک مخزن کوچک فقط با لوله های مسی یا JB`s DV-29 متصل کنید. سوپاپ خالی را مانند گذشته ببندید و تفاوت زیادی در میزان قرائت خواهید دید.

۷٫ شما با لوله مسی گفتید ، چرا شیلنگ شارژ نمی شود؟

لوله های مسی یا شیلنگ های فلزی مورد استفاده در JB`s DV-29 تنها راه های نگهداری خلاuum هستند. خلاuum برای نشت بسیار مهم است ، بیش از مبرد. شلنگ های شارژ ، از جمله شیلنگ های محیطی ، هنوز نفوذ می کنند. فراتر از نفوذ ، جایی که فرول شلنگ به سمت شلنگ جمع می شود ، نشان دهنده نشت احتمالی در خلا است. اتصال دهنده های سریع دارای واشر مهر و موم خوبی نیست. وقتی شعله ور شدن نر را به اتصال سریع واشر می اندازید ، واشر به چندین انحراف تبدیل می شود و به درستی آب بندی نمی شود. JB از حلقه های O روی اتصال دهنده های سریع ما استفاده می کند و هنگامی که شما شلیک نر را پیچ می دهید ، یک صندلی فلزی به فلزی پیدا می کنید و حلقه O در اطراف مشعل قرار می گیرد تا مهر و موم خوبی داشته باشد.

۸- پس این بدان معنی است که من نمی توانم خلا on سیستم خود را بکشم مگر اینکه از شلنگ فلزی یا لوله های مسی استفاده کنم؟

خیر ، می توانید با شلنگ های شارژ خلا را بکشید ، اما وقتی می خواهید سیستم را بررسی کنید تا نشتی نداشته باشد ، باید از لوله های مسی یا شیلنگ های فلزی استفاده کنید.

۹٫ وقتی که دارم خلاuum سیستم را می کشم اتصال سنج خود را به پمپ قرار می دهم ، آیا این درست است؟

بسیاری از تکنسین ها این کار را برای سهولت در اتصال انجام می دهند ، اما به یاد داشته باشید با این تنظیمات شما در واقع می خوانید که پمپ چه کاری انجام می دهد و نه اینکه پمپ چه کاری برای سیستم انجام می دهد. برای اثبات این نظریه ، یک سیم پیچ ۵۰ فوت از لوله مسی ۱/۴ “OD بردارید ، یک سر آن را یک شعله ور کنید و از طرف دیگر یک سه راهی را فشار دهید. یک سنج میکرون را به انتهای شعله ور شدن نر ، یک سنج را به انتهای آن متصل کنید و یک خط از سه راهی به پمپ باشد. پمپ را روشن کنید و متوجه خواهید شد که نزدیکترین طرف به پمپ بسیار پایین تر از دیگری است. در نهایت ، این مساوی می شود و همان خوانش را می دهد. این در سیستم رخ می دهد که روی آن خلا می کشید.

همیشه سطح روغن را با روشن بودن پمپ خلا بررسی کنید

همیشه سطح روغن را با روشن بودن پمپ خلا (وکیوم)بررسی کنید

پمپ های خلاac روتاری مهر و موم روغن برای استفاده در سیستم های آمونیا یا لیتیوم بروماید (آب نمک) در نظر گرفته نشده اند. هر دوی این سیستم ها باعث قفل شدن پمپ ها و غیرفعال شدن آنها می شوند. استفاده از پمپ های دوار مهر و موم روغن در هر یک از این سیستم ها ضمانت را باطل می کند. مهم- همیشه سطح روغن را در حالت پمپ بررسی کنید. دلیل این امر این است که اگر قبل از خاموش شدن پمپ ها خلا the شکسته نشود ، روغن موجود در پوشش خلا will موجود در کارتریج و محفظه ورودی را جستجو می کند. سپس سطح روغن در شیشه دید پایین می آید و ظاهر سطح روغن کم است. سپس اگر پمپ دوباره به خط سطح روغن پر شود و پمپ شروع به کار کند ، روغنی که دوباره به داخل کارتریج و محفظه مکش مکیده می شود دوباره به داخل درب لگد زده می شود و اکنون شما پر می شوید و روغن از بین می رود دسته (پورت اگزوز). حفظ عمر پمپ خود شامل برخی نکات عیب یابی است متقابل اندازه گیری های خلا Me دمای جوش آب مرجع متقابل در فشارهای تبدیل شده تست نشت دریچه ایزوله اصول خلا De عمیق شامل اطلاعاتی در مورد اندازه گیری تخلیه ، نحوه انتخاب پمپ خلا right مناسب ، استفاده از گیج سنج و نکات تخلیه است مقاله RSES در رابطه با روتاری مهر و موم روغن در اصول و کاربرد خلاac عمیق عیب یابی سنج دیجیتال / گرمای دیجیتال

IMPORTANT- Always check the oil level with the vacuum pump running

IMPORTANT- Always check the oil level with the vacuum pump running

oil seal  rotary Vacuum pumps are not intended for use on Amonia or Lithium Bromide (salt water) systems. Both of these systems will cause the pumps to lock up and be rendered inoperable. Use of oil seal  rotary pumps on either of these systems will void the warranty.

IMPORTANT- Always check the oil level with the pump running.

The reason for this is that if the vacuum is not broken before pumps are shut down the oil in the cover will seek the vacuum still in the cartridge and intake chamber. Then the oil level will drop in the sight glass and give the appearance of a low oil level. Then if the pump is refilled to the oil level line and the pump started, the oil that got sucked back into the cartridge and intake chamber will be kicked back into the cover and now you’ll be over filled and the oil will shoot out the handle (exhaust port).

 

https://pumpchat.ir


Keeping the Life of Your Pump
 includes some troubleshooting tips

Cross Reference of Vacuum Measurements

Cross Reference Boiling Temperatures of Water at Converted Pressures

Isolation Valve Leak Test

Principles of Deep Vacuum includes information on measuring evacuation, how to select the right vacuum pump, using a vacuum gauge and evacuation tips

RSES article in association with oil seal  rotary on Deep Vacuum Principles and Application

Troubleshooting Digital Superheat/ Subcooling Gauge (SH35N-SH36N)