Vacuum pumps are devices that remove gas molecules from an enclosed volume to create a partial vacuum. There are two main types of vacuum pumps: mechanical pumps, which use physical mechanisms like rotating pistons to compress and remove gases; and non-mechanical pumps, which absorb gases onto a cold surface or through momentum transfer without moving parts. Common vacuum pump technologies include oil rotary pumps, diffusion pumps, turbomolecular pumps, sorption pumps, ion pumps, and cryopumps. Each pump variety has its own applications and achievable pressure ranges, from rough vacuums of 10^-3 torr to ultra-high vacuums of 10^-12 torr.
Vacuum pumps are used in a variety of process plants to pump air, water vapor, organic and inorganic solvents and acids. There are many different types of vacuum pumps on the market today that meet special needs in pumping various gases.
Vacuum pumps are used in a variety of process plants to pump air, water vapor, organic and inorganic solvents and acids. There are many different types of vacuum pumps on the market today that meet special needs in pumping various gases.
College minor project and report seminar for electrical engineering student on Thermal power plant.
Project report on electricity generation in thermal power plant using coal.
A complete description of types of power plant, it's working.
Types of the turbine.It contains detail description of turbine, coal handling plant, ash handling plant, the layout of thermal power plant. Economizer, air pre heater, super heater etc. It also contains details description of thermal power plant in India.Also, describe boiler and its types.
College minor project and report seminar for electrical engineering student on Thermal power plant.
Project report on electricity generation in thermal power plant using coal.
A complete description of types of power plant, it's working.
Types of the turbine.It contains detail description of turbine, coal handling plant, ash handling plant, the layout of thermal power plant. Economizer, air pre heater, super heater etc. It also contains details description of thermal power plant in India.Also, describe boiler and its types.
Thermal conductivity can be defined as the rate at which heat is transferred by conduction through a unit cross-section area of a material, when a temperature gradient exits perpendicular to the area.
A theory of the specific heat capacity of solids put forward by Peter Debye in 1912, in which it was assumed that the specific heat is a consequence of the vibrations of the atoms of the lattice of the solid.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
4. Introduction
• Vacuum is a volume of space essentially empty of matter, such that its gaseous pressure is much less than
atmospheric pressure.
• Technically, vacuum refers to “The given space filled with a gas having density of molecules less then
2.5 *10^19 molecules / cubic cm at normal tempreature”
• Vacuum became a valuable industrial tool in the 20th century with the introduction of incandescent light
bulbs and vacuum tubes.
Vacuum pumps
History
• Before the vacuum pump, the suction pump was invented. In the city of Pompeii, dual-action suction
pumps were found.
• In the 13th century, an Arabic engineer also explained suction pumps. The suction pump later came up
again in Europe from the 15th century.
• By the 17th century, water pump designs had improved and they produced measurable vacuums, but this
was not understood immediately.
• It was understood by the people that suction pumps could not pull water beyond a certain height.
• Vacuum pump was invented in 1650 by Otto von Guericke
Defination
• A vacuum pump is a device that removes gas molecules from a sealed volume in order to leave behind a
partial vacuum.
5. Pumps can be broadly categorized according to three techniques:
• Positive displacement pumps use a mechanism to repeatedly expand a cavity, allow gases to
flow in from the chamber, seal off the cavity, and exhaust it to the atmosphere .
• Momentum transfer pumps or molecular pumps, use high speed jets of dense fluid or high
speed rotating blades to knock gas molecules out of the chamber .
• Entrapment pumps capture gases in a solid or adsorbed state. This includes cryopumps,
getters, and ion pumps .
Methods of vacuum pumps
There are two method to produce vacuum
1. Mechanical
2. Non Mechanical
Mechanical
The method in which a machine is used to reduce the momentum, number of particles or pressure
is called mechanical method.
It consists of three types of pumps:
1. Oil Rotary Pump
2. Diffusion Pump
3. Tarbomolecular Pump
6. Non Mechanical
The method in which momentum, number of molecules or pressure through a certain region is
reduced indirectly i.e to add momentum is called non mecanical method.
There are three types as follow:
1. Sorption Pump
2. Ion Pump and Getter-ion Pump
3. Cryo Pump
Mechanical Pumps
1. Oil Rotary Pump
• This is the oldest type of vacuum pump. The basic idea is to mechanically compress the gas (as
in a cylinder with a piston) and eject it into the atmosphere. The pump actually uses rotating
pistons and oil is used to provide a vacuum seal.
• The lowest achievable pressure is about 10^-3 torr.
• Oil rotary vacuum pumps are positive displacement vacuum pumps that use oil to reduce the
confidential and dead space between components such as the rotor, stator, and sliding vanes.
• The main limitation of this pumping technology is that oil vapors tend to slowly contaminate
the surfaces of the vacuum system.
Applications
Food, chucking, vacuum furnaces, leak systems, impregnation equipment, lasers, coatings,
chemistry, medical treatment, central vacuum systems.
7. Diffusion pumps
• These pumps use a jet of oil to push the gas and compress it. Hot and heavy oil molecules hit gas
atoms and push them out.
• The effect is similar to the downward air drift created in the shower that results in the shower curtain
being sucked in.
• Diffusion pumps compress the gas to about 10^-3 torr and have to be backed up with a roughing
pump.
• Diffusion pumps are fast and cheap, but they cause oil contamination especially if accidentally
exposed to atmospheric pressure. The minimum pressure is about 10^-8 torr.
8.
9. Turbo-pumps
• These pumps are basically super fans that push the gas with fast-moving blades.
• To achieve efficient operation the fan blades have to move close to the thermal speed of atoms, at several
hundred meters/sec.
• Turbo-pumps have several hundred blades and rotate at about 70000 revolutions per minute.
• Modern turbo-pumps can withstand accidental exposure to atmospheric pressure.
• The minimum pressure is about 10^-9 torr.
Applications
Turbomolecular pumps are used in a wide range of high and ultra-high vacuum applications,
covering both clean applications (e.g. in analytical instruments or R&D), and very harsh applications in
Semiconductor industry where the pumps have to handle corrosive gases or critical process conditions.
10. Non Mechanical
Sorption Pump
• These pumps do not compress and eject the gas, but absorb it inside the pump.
• They typically use charcoal or similar porous material with a very high surface area.
• When the charcoal is cooled with LN2 most gases stick to its surface.
• The gas drawn through the inlet part inflow into a chamber with a porous adsorbent, Molecular
Sieves. The molecular sieves cooled by the liquid nitrogen outside the chamber adorbs the gas in
the chamber. Finally, the inside of the pump is evacuated.
• This pump is fast, clean, and can achieve low pressures, but has a limited pumping capacity before
it has to be regenerated by warming up the charcoal.
Applications
More recently, partially automated sorption pumps have been used for repetitive rough pumping of
production coating systems. There have also been experimental uses of sorption pumps as fine
pumps in the 10^-6 Torr range, as an air sampler, and for argon pumping in a sputtering system.
11.
12. Getter-ion Pump
• Ion getter pumps (IGP) are devices able to create and maintain ultra-high-vacuum, reaching pressures as
low as 10^-12 mbar.
• Lower pressures are in principle achievable, but their measurement is particularly challenging and
strongly depends on the outgassing of the system on which the ion pump is mounted.
• With respect to other vacuum pumps, such as turbomolecular pumps or primary pumps, IGP have some
characteristics that make them unique.
• The ion pump is a static device. It has no moving parts, so it is vibration free and, consequently, it
doesn’t need any lubricant which could be a source of contamination.
Applications
• Ion getter pumps are frequently used in general UHV systems, surface analysis, and high-energy
physics applications.
• As well as producing UHV pressures, ion getter pumps are: Hydrocarbon-free. Operable at high
temperatures.
13. Cryo Pump
• This pump features a clean vacuum and high pumping speed.
• A cryopump is an accumulating type vacuum pump. The pump condenses and adsorbs gases on a cryogenic
surface installed in the pump to create a condition from high vacuum to ultra-high vacuum. Also, this pump
can obtain a clean vacuum that is not contaminated by oil and has a higher pumping speed than other
vacuum pumps, which attracts attention.
• A cryopump is vacuum pump that traps gases and vapors by condensing them on a cold surface. For
efficient evacuation under ultra-high vacuum, the vapor pressure for condensation, or the equilibrium
pressure for adsorption must be less than 10-8Pa.
Mechanism of Cryopump
Higher vacuum with two-stage
Cold stage is a two-stage type. The cooling capacity of the first stage is large, and it can cool to 80 K (Kelvin)
or less. First-stage exhausts mainly the moisture and the second stage exhausts molecules such as N2, O2, Ar,
and H2 by cooling even further to obtain a higher vacuum.
The reason for the ultra-low temperature.
• Gas molecules condense and adsorb on contact with a surface that is cooled close to 0K = absolute zero (-
273.15 ° C).
Electronic components such as semiconductors, liquid crystals, and disks, eyeglass lenses, and extra-
large space vacuum chamber.