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Mechanical Engineering

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    Cutting fluids are the fluids which are generally applied while the machining (or cutting) operation is taking place.
    Advantages of cutting fluids
    The advantages of cutting fluids in machining operation are : 
    Increase tool life by cooling the cutting edge. Decrease tool-chip friction by providing a lubricant between chip and tool. Provide better finish on the workpiece. Reduce forces on the tool and hence economize in power consumption. Cool workpiece to maintain its dimensional accuracy, by reducing or eliminating distortion caused by heat generation. Decrease the tendency to form a 'built-up edge'. Flash away chips. Lubricate guiding portions of tooling, such as a drill or pilot in a bush. Discourage corrosion of newly machined surfaces. Lubricate machine movements.   The requirements of a cutting fluid are :
    The fluid should be efficient coolant and provide effective lubrication. It should be easy to handle, prepare and store. It should have optimum service life and minimum cost, and have no ill-effects on normal machine lubrication, and be non-injurious to health (non-toxic, non-fuming) and odourless. Further it should be non-corrosive to machine, tooling or component.
     
    Types of cutting fluids
     The four types of cutting fluids commonly used are described below in brief:
    1. Aqueous fluids are usually emulsions, known as soluble oils. They are generally cheapest and find greatest use where coolant properties are the important factor, such as conventional cutting of metals with high speed steel tools. 2. Oil-type fluids are straight petroleum products, usually known as neat cutting oils or mineral oils. They are generally used when reduction of friction is important and the presence of the water in a soluble oil emulsion is undesirable. Heavy duty cutting can break down the emulsifier of a soluble oil, and the water would tend to flush out the natural lubrication of the machine. Oil-type fluids find considerable usage on automatic lathes. 3. Synthetic fluids form solutions, not emulsions, in water. These solutions are transparent, allowing operators to observe the cutting, and are mainly used on grinding machines. 4. Gaseous fluids, such as carbon dioxide, have limited application, due to high cost, but are occasionally used when liquids have to be avoided, such as when cutting an absorbent material use of Additives in cutting fluids
    It is very common to use additives to cutting fluids to obtain following qualities : act as a wetting agent; discourage foaming ; stabilize an emulsifier; discourage bacterial growth; act as a rust inhibitor ; act as an antiseptic. The most common additive is sulphur. It acts as en anti-weld agent discouraging the formation of the built-up edge and reacts with the chip to form solid lubricants on the chip surface.

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    Following principles must be followed  as the principles of safe design of machines from consideration  of accident prevention.
    Dangerous moving parts should be enclosed. Parts subject to wear, adjustment, and hand lubrication should be conveniently  accessible. Lubrication should wherever possible be automatic and continuous when the machine is in operation Consideration should be given to individual drive so that hazards due to driving mechanism may be minimized. Sharp contrast between light and shadow and glare in the vicinity of the point of operation should be considered, also the provision of integrally mounted lights and the probable position of independent lighting units. Materials should be mechanically conveyed to, and removed from machine whenever possible. Provision should be made for automatically conveying dust and gases away from machine. Noise should be eliminated or reduced to the maximum extent.   Machine motions tiring to the eyes should be avoided. Exterior shapes of any parts of the machines that requires frequent contacting or handling should be such as to facilitate convenience in handling and moving parts that cannot be enclosed should, as far as possible, be smooth in contour. Weight of parts to be handled should be kept within the limits of convenience, or these parts should be so designed that they may be conveniently handled by mechanical means. Throughout the design of the machine and its parts, consideration should be given to convenience in attaching accessories, chiefly point-of-operation guards or moving parts. Consideration in design should be given to the external shape of the machine unit so that the danger of accident from tripping and falling and collision will be minimized. Corners may often be rounded to lessen the danger from accidental contact. Liberal factors of safety should be used in determining the strength of parts. Wherever manufacturing circumstances permit, point-of-operation guards should be installed by the builder of the machine so that it may be delivered to the purchaser in a fully guarded condition. Consideration should be given to the safe location or isolation of machines that cannot be made safe otherwise. Please add your on inputs or missing points in the comment box

    Osama Khayal
    The effect of several hot pressing parameters on the internal mat environment was
    investigated by using the mathematical model and the results were compared to data collected experimentally. The different pressing parameters included three initial mat moisture contents (5, 8.5, 12 %), three final panel densities (609, 641, 673 kg/m3 or 38, 40, 42 lb/ft3), two press platen temperatures (150, 200 °C), and three press closing times (40, 60, 80 s). The variation of temperature and total gas pressure during the press cycle at six points in the vertical mid-plane of a single layer, random mat structure was predicted with the heat and mass transfer model using the different pressing conditions. Twenty-four boards were manufactured according to the same
    specifications, and the temperature and internal gas pressure were measured with thermocouples and gas pressure probes at the same six locations. The model predicted data described the major trends during the hot-compression operation qualitatively. However, further work is needed to make quantitative predictions.
    A hot-compression model was developed based on fundamental engineering principles. The material physical and transport properties were the best available values from the literature or best estimates based on engineering judgment. A sensitivity study assessed the relative importance of the different transport properties during the hot-compression process. The response of selected variables of the hot-compression model for a perturbation of the parameter values was investigated. The sensitivity analysis of the model parameters revealed
    that the thermal conductivity and gas permeability of the mat have the greatest influence on model results. The assessment of these transport properties experimentally, as a function of mat structure, is highly desirable and can considerably improve the model predictions.
    EFFECT OF HOT PRESSING ON THE INTERNAL MAT ENVIRONMENT.pdf

    Osama Khayal
    Very little investigation has been carried out to study the performance of flat heat pipes, though researchers recently turned their attention to the same. The results of the literature review on heat pipes indicate the necessity and scope for further theoretical and experimental studies on flat rectangular heat pipes. The present work is an attempt to study the steady state operation of the flat rectangular heat pipes, both theoretically and experimentally. It also aims at the study of the influence of the amount of working medium and wick porosity on the performance of heat pipes.
    Heat Transfer and Fluid Flow Studies on Flat Heat Pipes.pdf

    Osama Khayal
    This research study has been done in Aljabalein Power Plant at White Nile State. The objective of the study is to compare and differentiate between two types of fuel, light fuel oil (LFO) and crude oil (CRO) used in power plant situated in Aljabalein site. The comparison have been done on different viewpoints including the impact of exhaust gases on the surrounding environment, the performance of engines at different loads, and the operation and maintenance costs. It is found that CRO fuel oil is preferred to LFO fuel due to less operation costs. But it has many disadvantages such as high pollution rates and high consumption of spare parts.
    Technical and Environmental Study On Using Light Fuel Oil and Crude Oil in Internal Combustion Engines (ICE).pdf

    Osama Khayal
    Chemical engineers are accustomed to software for designing processes and simulation. Simulation systems such as Matlab and Aspen Plus are commonly referenced in chemical engineering curricula as required courseware and study tools. Automation professionals are also becoming used to applying simulation to operator training, system testing, and commissioning of plant process control systems. Plant
    design simulation programs are substantially different from systems used for training and commissioning. Many of the most common plant design simulation programs are steady state, low-resolution simulations that are not usable for automation or plant life-cycle management.
    SIMULATION AND DESIGN SOFTWARE SYSTEMS FOR TESTING AND TRAINING PROCESS AUTOMATION PROJECTS.pdf

    Osama Khayal
    Hydropower is important from an operational standpoint as it needs no "ramp-up" time, as many combustion technologies do. Hydropower can increase or decrease the amount of power it is supplying to the system almost instantly to meet shifting demand. With this important load-following capability, peaking capacity and voltage stability attributes, hydropower plays a significant part in ensuring reliable electricity service and in meeting customer needs in a market driven industry. In addition, hydroelectric pumped storage facilities are the only significant way currently available to store electricity.
    Water is one of our most valuable resources, and hydropower makes use of this renewable treasure. In managing hydropower, Reclamation is helping the Nation meet its present and future energy needs in a manner that protects the environment by improving hydropower projects and operating them more effectively.
    REVIEW AND TECHNICAL STUDY OF HYDROELECTRIC POWER GENERATION.pdf

    Osama Khayal
    Composite materials have been utilized to solve technological problems for a long time but only in the 1960s did these materials start capturing the attention of industries with the introduction of polymeric-based composites. Since then, composite materials have become common engineering materials and are designed and manufactured for various applications including automotive components, sporting goods, aerospace parts, consumer goods, and in the marine and oil industries. The growth in composite usage also came about because of increased awareness regarding product performance and increased competition in the global market for lightweight components.
    Among all materials, composite materials have the potential to replace widely used steel and aluminum, and many times with better performance. Replacing steel components with composite components can save 60 to 80% in component weight, and 20 to 50% weight by replacing aluminum parts.
    MANUFACTURING AND PROCESSING OF COMPOSITE MATERIALS.pdf

    Osama Khayal
    The article presents a brief outline of the history of  Bajaj rickshaw vehicles industry. Vehicle design, the incorrect usage of petrol and lubricating oil mixture, safety risks in riding rickshaw, and environmental impact  were integral activities. Almost all of the engine designers mentioned in the article also were automobile designers, and a few went on to become major manufacturers of automobiles. All of these inventors and more made notable improvements in the evolution of the Bajaj rickshaw vehicles.
    LITERATURE REVIEW ON THE HISTORY OF BAJAJ RICKSHAW VEHICLES.pdf






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