22-04-2010, 10:09 AM
pls send me the full seminar report on pneumatic systems
22-04-2010, 10:09 AM
pls send me the full seminar report on pneumatic systems
25-04-2010, 09:46 PM
Pneumatics is the use of pressurized gas to affect mechanical motion.This field deals with the use of pressurized gas to affect mechanical motion.
Examples of pneumatic systems: # Air brakes on buses and trucks, trains # Compressed-air engine and compressed-air vehicles # Gas-operated reloading # Pneumatic actuator # Pneumatic air guns # Pneumatic cylinder # Pressure regulator # Pressure sensor and much more. Gases used: compressed air is used by Pneumatic systems in fixed installations such as factories. a small quantity of oil and moisture are added to avoid corrosion . nitrogen - often referred to as OFN are used by Factory-plumbed, pneumatic-power users. Compressed oxygen is never used in pneumatically powered devices as it accelerates combustion. Advantages of pneumatics -Simplicity of Design And Control -Storage -Reliability: they tend to have long operating times. . -Safety Pneumatic power generation and control The turbine engine is a generator of high-speed gas aimed to provide thrust for the aircraft.In this kind this kind of compressed air generation: a)the system needs a regulation, because bled air conditions depend on engine functioning conditions b) a reduced amount of air can be bled from the compressor to avoid significant breakdown in engine performance. for details refer: pnemuatic systems.PDF (Size: 124.66 KB / Downloads: 880) http://en.wikipediawiki/Pneumatics
02-04-2011, 10:28 AM
Submitted By: Sanjay Singh New Microsoft Office PowerPoint Presentation (2).pptx (Size: 74.49 KB / Downloads: 219) PNEUMATIC SYSTEM INTRODUCTION In many cases energy from compressed air has different advantages on board, especially when the aircraft is powered by turbine engines because air can be easily bled from the compressors. Air is present at high pressures and temperatures and then, after regulation, can be used for heating and pressurization. Environmental control. Pressurisation for hydraulic oil reservoir, fuel tanks, water tanks. PNEUMATIC CONTROL SYSTEM Separated into four main groups 1- Air Compressor stations 2- Transmitters and Controllers 3- Auxiliary devices 4- Controlled The Uses Are Located In Different Areas Of The Aircraft; Like The Hydraulic System. The principal use of the pneumatic system is the environmental control on large airliners . The pneumatic system is normally made of a number of sub-systems equal to the number of engines. Ice protection system may request an important flow rate of hot air in some parts of the flight mission, usually during climb. PNEUMATIC USES Controlled devices Applications Construction Equipment Factory Automation Aircraft Flight Systems Shipboard Controls Military Vehicles Pneumatic Control System Applications 1- Most common in large commercial applications such as schools & hospitals 2- Central air handler units 3- Boilers 4- Chillers 5- Cooling tower systems ADVANTAGES Reliable, economical actuators. Flexible, modular control components. They require essentially no maintenance except for inspection and adjustment of the mechanical linkages. Pneumatics can provide excellent control performance and can maintain set points accurately. DISADVANTAGE Air stations require routine maintenance May require specialized tools for set-up and calibration Technician has to be onsite to check the system. CONCLUSION Pneumatic controls have been used successfully in commercial buildings for decades. Systems today are operating with control components that are 40 to 50 years old. On the other hand, there have also been cases where pneumatic systems have been pulled out and replaced because of perceived poor performance. New Microsoft Office Word Document (2).docx (Size: 422.02 KB / Downloads: 214) ABSRRACT Control system utilize pressure differential created by gas source to drive the transfer of material. Pneumatic control system are all about using compressed air to operate and power a system air taken from the atmosphere and squeezed are compressed .This compresed air is then used a pneumatic system to do work . Pneumatic system are used in Meany field such as lorry brake, bicycle tyres, car tyres, paint spraying aircraft and hydraulic system In this paper, we propose an intelligent control method for a pneumatic servo nonlinear system with static friction. The real machine experiment confirmed the improvement of the speed of response and the stop accuracy and the effectiveness of the proposed method. INTRODUCTION In many cases energy from compressed air has different advantages on board, especially when the aircraft is powered by turbine engines because air can be easily bled from the compressors. Air is present at high pressures and temperatures and then, after regulation, can be used for heating and pressurization. Main uses are as follows: • Environmental control; • Ice protection; • Windscreen demisting and rain dispersal; • Pressurisation for hydraulic oil reservoir, fuel tanks, water tanks; • Turbine engine start; • Turbines; • Actuators (under very restricted conditions).[1] PNEUMATIC POWER GENERATION AND CONTROL The turbine engine is a generator of high-speed gas aimed to provide thrust for the aircraft. Before entering the combustion chamber and being mixed with atomized fuel, the external air is processed by a multi-stage axial compressor, driven by the turbine. From one or more stages of the compressor, a limited volume of air can be bled without significant degradation of the engine performances. Then the engine compressor is responsible for the pneumatic power generation on board. Two remarks are relevant for this kind of compressed air generation: 1. The system needs a regulation, because bled air conditions depend on engine functioning conditions and these vary from idle (low pressure and temperature) to max thrust (high pressure and temperature); 2. In some flight conditions a reduced amount of air can be bled from the compressor to avoid significant breakdown in engine performance, especially when max thrust is requested. The sketch in fig. summaries the components of pneumatic system generation for a turbofan engine. Air is commonly bled at two different stages of the compressor: a low pressure port at an intermediate stage (around 7TH stage) and a high pressure port at a final stage (around 15TH stage). A check valve is necessary to prevent air flowing from high to low pressure bleeding ports. The low pressure bleeding port is normally open, but can be excluded with the shut-off valve if the engine is in critical conditions; the high pressure port is open when the pressure coming from the intermediate stage is not adequate, or a considerable amount of air is necessary, and anyway the engine must be in operating conditions that cannot be deteriorated by intensive air bleeding: typically this bleeding is operated during taxiing or descent, with the engine near idle. A low flow rate can be engine, between 2 and 8 % of the total flow rate processed, but a significant amount of energy content. The same amount of energy is obtained by compressed air extracted from the APU, but the bleeding rate is here around 70-80% of the total flow rate, because the APU is not finalized to generate thrust with the exhaust gases. This allows operation of all pneumatic uses when the aircraft is on ground with engines off, in particular the environmental control system and engine starting. Bleed air conditions from the compressor stages range, for a modern turbofan, from 0.2 to more than 1 MPa in pressure and from 180 to more than 350 °C in temperature, depending on altitude and engine speed. Because the generated air is at a temperature higher than that requested by the uses, and may be too hot to be canalised safely to other regions of the aircraft, it is cooled through a heat exchanger with fresh external air before going to the pneumatic system delivery. By metering the fresh cooling air with a flow rate regulator, the compressed air temperature is controlled, usually for a final temperature around 175 °C. Moreover a regulator on the compressed air line keeps the pressure to system at about 0.3 MPa. PNEUMATIC USES The uses are located in different areas of the aircraft; like the hydraulic system, the pneumatic system is normally made of a number of sub-systems equal to the number of engines, capable of operating separately different uses but with the possibility of a full cross-feed in case of malfunction of the power generation in one sub-system. The principal use of the pneumatic system is the environmental control: on large airliners this may request an intense flow rate of compressed air to keep suitable environmental conditions in the cabin. This subject will be treated in a specific chapter. Ice protection system may request an important flow rate of hot air in some parts of the flight mission, usually during climb. This subject will be treated in a specific chapter too. Windscreen demisting, rain dispersal and reservoir pressurisation request low flow rate. Compressed air from APU of from ground compressors is used to start large turbine engines. Sometimes the aircraft is equipped with small turbines that, in emergency conditions, can be operated by the pneumatic system to drive hydraulic pumps or electrical generators
22-03-2012, 06:14 PM
please send me yhe infornation report about pneumatics
please send report about pneumatics..systems
23-03-2012, 10:14 AM
to get information about the topic " pneumatic system" full report refer the link bellow https://seminarproject.net/Thread-pneumatic-system
01-09-2012, 03:23 PM
PNEUMATICS
PNEUMATICS.docx (Size: 88.64 KB / Downloads: 40) PNEUMATICS neumatics is a branch of technology, which deals with the study and application of use of pressurized gas to affect mechanical motion. Pneumatic systems are extensively used in industry, where factories are commonly plumbed with compressed air or other compressed inert gases. This is because a centrally-located and electrically-powered compressor that powers cylinders and other pneumatic devices through solenoid valves is often able to provide motive power in a cheaper, safer, more flexible, and more reliable way than a large number of electric motors and actuators. Pneumatics also has applications in dentistry, construction, mining, and other areas. GASES USED IN PNEUMATIC SYSTEMS: Pneumatic systems in fixed installations such as factories use compressed air because a sustainable supply can be made by compressing atmospheric air. The air usually has moisture removed and a small quantity of oil added at the compressor, to avoid corrosion of mechanical components and to lubricate them. Factory-plumbed, pneumatic-power users need not worry about poisonous leakages as the gas is commonly just air. Smaller or stand-alone systems can use other compressed gases which are an asphyxiation hazard, such as nitrogen - often referred to as OFN (oxygen-free nitrogen),when supplied in cylinders. Any compressed gas other than air is an asphyxiation hazard - including nitrogen, which makes up 77% of air. Compressed oxygen (approx. 23% of air) would not asphyxiate, but it would be an extreme fire hazard, so is never used in pneumatically powered devices. Portable pneumatic tools and small vehicles such as Robot Wars machines and other hobbyist applications are often powered by compressed carbon dioxide because containers designed to hold it such as soda stream canisters and fire extinguishers are readily available, and the phase change between liquid and gas makes it possible to obtain a larger volume of compressed gas from a lighter container than compressed air would allow. Carbon dioxide is an as phyxiant and can also be a freezing hazard when vented inappropriately. COMPARISION TO HYDRAULICS: Both pneumatics and hydraulics are applications of fluid power. Pneumatics uses an easily compressible gas such as air or a suitable pure gas, while hydraulics uses relatively incompressible liquid media such as oil. Most industrial pneumatic applications use pressures of about 80 to 100 psi (550 to 690 KPa) . Hydraulics applications commonly use from 1,000 to5,000 psi (6.9 to 34 MPa) , but specialized applications may exceed 10,000 psi (69 MPa). ADVANTAGES OF PNEUMATIC SYSTEM: Simplicity of Design And Control Machines are easily designed using standard cylinders & other components. Control isas easy as it is simple ON - OFF type control Reliability Pneumatic systems tend to have long operating lives and require very little maintenance. Because gas is compressible, the equipment is less likely to be damaged by shock. Thegas in pneumatics absorbs excessive force, whereas the fluid of hydraulics directly transfers force. Storage Compressed Gas can be stored, allowing the use of machines when electrical power islost. Safety Very low chance of fire (compared to hydraulic oil). Machines can be designed to be overload saf USES OF PNEUMATIC CYLINDERS: Pneumatic cylinders turn air pressure into linear motion. They are like automobile pistons except the piston (and connecting rod) is pushed by an influx of pressurized gas instead of a gasoline explosion. The piston must be returned to the starting position after each stroke. If a spring is used to return the piston, it is a single acting cylinder. If air pressure is used to return the piston, it is a double acting cylinder. INDUSTRIAL USES: Double acting pneumatic cylinders are more expensive than single acting pneumatic cylinders, but double acting cylinders are superior to single acting cylinders by any other important measure. Double acting cylinders are faster, stronger and use less energy to do the same job. In industrial applications, single acting cylinders are used if possible, but when speed or force is important, double acting cylinders are employed. Applications include opening and closing valves and doors, taking things off conveyor belts and putting things on conveyor belts .They are also used for lifting merchandise and moving merchandise around as well as for presses and punches. ROBOTIC USES: Pneumatic cylinders including double acting cylinders have been an important component of robots since the introduction of Mc Kibben artificial muscles. Robotic arms move in a much more natural way if the arms are fitted with muscles resembling those of the human arm. Mc Kibben artificial muscles consist of rubber tubes enclosed in a metal mesh. When the rubber tubes are inflated, the metal mesh expands in diameter and decrease in length—pulling the arm. Arms (both artificial and natural) really have two sets of muscles--one on the front(biceps) to decrease the joint angle and another on the back of the arm (triceps) that increases the joint angle. Because these muscles must work together, the pressures must be coordinated very quickly, so double acting cylinders are essential for supplying air to the Mc Kibbens. OTHER USES: Double acting cylinders are used in automobile, motorcycle, Automated Transfer Vehicle (ATV) and airplane landing gear suspensions because the bumps come so fast that a single acting cylinder would be impractical. Double acting cylinders are used in drilling, log splitters and earth moving equipment because the forces required make single acting cylinders impractical. Double acting cylinders are found in back hoes, elevators, trash compactors, garbage trucks, fork lifts, jacks and those machines in junk yards that compress old cars. They are also used in medical applications that power ventilators--those machines that help people breath. OVERVIEW OF PNEUMATIC CAN CRUSHER: A can crusher is basically used to smash empty aluminum cans so as to decrease the volume of waste disposal. You can save considerable amount of storage space by purchasing a can crusher. Although, there are different styles and sizes available in can crushers, the most preferred one is the pneumatic can crusher. This tool is capable of crushing a can into the smallest possible unit. These devices are commonly seen in bars, restaurant sand catering halls. Even heavy drinkers keep this device in their home in order to
08-10-2012, 01:20 PM
to get information about the topic "pneumatic system" full report ppt and related topic refer the link bellow
https://seminarproject.net/Thread-pneumatic-system https://seminarproject.net/Thread-pneuma...ing-system https://seminarproject.net/Thread-pneuma...tem?page=2 |
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