Applications of Pneumatics and Hydraulics - Essay Example

APPLICATIONS OF PNEUMATICS & HYDRAULICS INTRODUCTION The aim of the assignment is to understand and beware of the basic components in pneumatics and hydraulics. At the same time it helps introduce us to important but relevant international standards plus the H& S legislation. The initial basic understanding of the function of component contributes to our future design knowledge. ANALYSIS SECTION 1 A 1. 3/2 spring return operated by push button Three way valves have three working ports which are inlet, outlet and exhaust. They work on two way by allowing fluid to the actuator but at same time accept the fluid that return from it. The DCV valves perform three functions namely: i) stopping the fluid from flowing; ii) Allow fluid to flow: and iii) they change the direction of the fluid flow (Bud, 2008) Fig1: 3/2 spring return operated by push button 2. 5/2 Pilot operated DCV The DCV valves perform three functions namely: i) stopping the fluid from flowing; ii) Allow fluid to flow: and iii) they change the direction of the fluid flow. Fig 2: 5/2 Pilot operated DCV 3. 5/3 Pilot operated spring return to centre (all ports closed) DCV Fig3: 5/3 Pilot operated spring return to centre (all ports closed) DCV 4. AND gate Basically AND gate is a logic gate that only has a full output if both the input are high, otherwise no output completely. Therefore if say A& B are input, AND gate will record a 1 or High if the input is A&B otherwise the result is 0 (negative). Fig 4. AND gate 5. OR gate This is the reverse of the AND gate, OR gate record a HIGH if both or either of the two record a positive. Therefore if say A& B are input, OR gate will record as 1 or High if the input is A, B or A&B. Fig 5: OR gate 6. Air service unit The role is to improve the quality of the intake air through contamination elimination and pressure regulation hence helps increase operation reliability and efficiency. Fig6: Air service unit 7) 5/2 Solenoid operated DCV Fig 7: 5/2 Solenoid operated DCV 8) 3/2 P/O Spring Return DCV (Normally open & normally closed) 9) 3/2 spring return operated by rocker 10. One way flow restrictor Fig 10: One way flow restrictor This is a kind of check valve, it allow fix amount of flow in one direction only. The free space at the top ensures fixed amount of fluid passes through, hence there is a variable but one way version. SECTION 1B Pneumatic system has more industrial applications as compared to the hydraulic systems. Pneumatic uses the energy from the gas why hydraulic uses liquids which is normally incompressible (Goel, 2011). Pneumatic have the following advantages over hydraulic: Low initial cost of the pneumatic components. Can sustaining condition where they are overloaded. Long distance transmission is ideal and easier with pneumatic system Long life especially the actuators and low maintenance cost Low fire chances hence safe The figure below is a hydro-pneumatic suspension systemized in the motor vehicle induced in the suspension system. Fig 8: schematic of a hydro-pneumatic suspension system Source (Bauer & Fischer, 2013).) The system has combined the pneumatic and the hydraulic technologies in coming up with the following suspension system. SECTION 1C PNEUMATIC “SERVICE SYSTEM” Installation should follow the arrangement of the drawing with every device placed in the ideal position. However during installation the person involve has to ensure that all the devices are functioning on their own to avoid unnecessary trial and error methods of trouble shooting in case it fail to function. Figc1: Pneumatic service system Intake air filter: are used to remove contaminants from the compressed air. Compressor: Has the role of compressing air to the required pressure and convert the mechanical energy transferred from the motor plus the engine into potential energy. Normally it supplies various pneumatic components in the system with the compressed air. It draws its air from the earth surface under normal condition but raises it quality to above the pressure in the atmosphere. After cooler: It removes the moisture content and can also be used to eliminate the impurities therefore it improves the air quality. They are normally provided between the successive stages of a multi-stage compressor to remove the heat hence it reduces the role of compressor (Gupta, Asthana & Gupta, 2008). Air separator/water separator: its role is to remove unwanted liquid in form of water or oil. Pressure switch: Type of switches that complete the electrical circuit when certain quantity of input pressure is achieved. Safety valve: This are valve that are used to create safety within the system since they react to free the system over built up pressure that is excess of the required standards. Air Receiver: This is used to improve the efficiency of the compressor or the system. Air service unit: the role is to improve the quality of the intake air through contamination elimination and pressure regulation hence helps increase operation reliability and efficiency. Safety concerns Compressed air should not be let into the body through any opening. Never spray anyone with compressed air Compressed air can pass through human skin. Exhaust from compressed air should not access the eye due to particles and oil droplets that could destroy the world. Turn off immediately y incase off leakage. Install switches on the compressed air supply to allow easy and speedy air flow Thorough circuit inspection before system pressure is increased as there may be weak or loose pipe somewhere. The following are the help Health and safety requirement for the installation of a pneumatic service system: 1. Use safe and suitable equipment: this will be only achieved with the proper design factors and standards considered. 2. Understand the operating conditions: you should have information like pressure and temperature. Operating instruction should be given for the system control 3. Protective devices necessary: the system should have safety devices such as safety valve check valve and electronic control devices for automatic shutdowns. They should be kept in good shape and working operation 4. Carry out suitable maintenance: Maintenance .help keep the system in the best working conditions by taking through proactive maintenance/preventive maintenance. 5. Have the competent equipment controller: this will help in quality service and proper efficiency management. 6. Have equipment examined by the under pressure system safety regulation 2000 so that they determine their usability Source: (HSE, 2012). SECTION 1D 1) Pneumatic accumulator/reservoir This is used specifically for storage especially for fluid that is under pressure but impossible compressing. It also provides a large surface area that helps transfer heat to the surrounding and has to have enough volume to slow down the incoming velocity. It helps remove the contaminant from the system and add new required fluid. The function of the power stored in the accumulators is for the following functions: Keeping power for incase duty cycle hence the pump drive power is economized. Provide the so much needed standby power for emergency. Vehicle suspension As s dumping agent for pulsation and shock which are periodic in nature. 2) Hydraulic reservoir This is used specifically for storage especially for fluid that is under pressure but impossible compressing. It also provides a large surface area that helps transfer heat to the surrounding and has to have enough volume to slow down the incoming velocity. It helps remove the contaminant from the system and add new required fluid. The accumulators are based on the principle of incompressible fluid and compressible air. They normally need a varying flow but intermittent flow rate. The accumulator normally will accept output flow when the system demand is low and supplement the output when the demand is now higher. NB: Most accumulators combine the pneumatic and hydraulic technology hence will have a gas separator which is normally a piston that separates the air from the liquid. Hydro-pneumo accumulators combine the two hair method which has diaphragm or at times a bladder used as the separator. Figd2: Hydraulic reservoir 3) Fluid power pumps This is a mechanical device that converts the mechanical energy into the hydraulic knowledge and it help overcome the load. The mechanical action create a vacuum in the inlet pump hence the atmospheric pressure force the fluid normally in the reservoir into it. These pumps are normally driven by prime mover such as IC engine. Figd3: hydraulic pumps 4) Fluid power motors Fluid power motors convert the fluid energy into mechanical energy which is transmitted to the load through as shaft connection. Fig d4: Fluid power motors References Bauer, W & Fischer, M (2013). Hydro-pneumatic suspension system: faster and more cost Effective development. ARGO-HYTOS. http://www.argo-hytos.com/en/news/products-application/article/hydro-pneumatic-suspension-systems-faster-and-more-cost-effective-development.html Retrieved [6/12/2014] Bud, T (2008).Directional control valve. Hydraulic & Pneumatics http://hydraulicspneumatics.com/other-technologies/book-2-chapter-8-directional-control-valves Retrieved [6/12/2014] Gupta, K.P, Asthana, S .P & Gupta, N (2008).A Study based on design of air compressor. Intercooler. International journal of research in Aeronautical and mechanical engineering. ISSN (Online):2321-3051 Goel, T (2011).Advantages of pneumatic over hydraulic. Bright Hub Engineering http://www.brighthubengineering.com/fluid-mechanics-hydraulics/19006-advantages-of- pneumatics-over-hydraulics/ Retrieved [6/12/2014] HSE (2012).A guide for safety: Pressure system www.hse.gov.uk/pubns/indg26.htm Retrieved [8/12/2014] Appendix Table1: types of energy stystems The table below try to show the differences between different power controlled system hence it give clear view of the diffrence between electrica system,hydraulic system and pneumatic system Read More