Compressor and Pump - Term Paper Example

Name Tutor Course Date Part 1 (Compressor) Introduction A compressor is a mechanical device that decreases the volume of air or natural gas through application of pressure. The compressed air has various applications which include providing power to pneumatic tools. There are different types of compressors ranging from simple models to more complex models. The simple types of compressors are the ones used to inflate air into tires of motor vehicles and bicycles. The complex types are used together with other different types of machines. During drilling using rotary drilling rigs, a compressor that is advanced is used to flush out cuttings in the borehole through the use of compressed air. Most compressors use air as compared to other gases. The compressors are able to compress the air by the use of a piston that is inside a series of cylinders. The compressed air is used depending on the amount of work done. There are several types of compressors in use today. The most common types include the rotary-screw compressors, centrifugal compressors and reciprocating compressors (Engineering tool box, 2012). The se compressors have different working principles due to their components and the arrangement of devices. The capacity of the compressors also differs depending on the size and type. The efficiency of the compressors is usually determined through calculations. This is important in determining the right compressor to be used for a particular task. The paper will analyze in details the various types of compressors, their efficiencies, capacity and the components of a compressor. Rotating equipment Rotating equipment is a term used to describe machines that adds kinetic energy to a process. This kinetic energy may be used in turn to move materials from one point to another. The compressor can be classified as a rotating equipment since is used to add kinetic energy to a process. This is mainly achieved through the use of the compressed air. An example that best describes the compressor as being a rotating equipment is the rotary drilling operation. This may include the drilling of water or exploratory drilling of minerals. The rotary drilling rig is usually connected to a air compressor. The rig does not have the mechanism of removing the cuttings from the borehole. The compressor is thus used to add energy to this process by removing the cuttings. This operation cannot be completed without the compressor. This therefore shows that the compressor can be classified as rotating equipment. The addition of kinetic energy causes motion which is moving materials from one point to the other. Compressor overview The overview of the compressor is generally the elements that make up the compressor. This is also the main elements and mechanism that is used by all the compressors. The compressor must have a mechanism of driving it in most cases engines are used to drive the compressors. The air is sucked into the compressor by the engine. A compressor may be composed of other multiple compressors that will ensure the compressors meet the working standards. Ay compressor should have a drier or a conditioning system. This system is responsible for removal of unwanted materials that may end up affecting the component that is using the compressor. Other foreign materials being removed include water, oil or any other contaminant that may try to be absorbed. To maintain the pressure in the system, it is necessary to have a pressure control. This is found in any compressor. It is also used to maintain the air and the pressure. The load system is used to determine the capacity of the compressor. This system is also useful in ensuring that the compressor does not overheat and ventilation is maintained. This system ensures that the compressor will operate properly. Most compressors have a system that maintains flexibility for the purpose of ensuring it adapts to different loads. The compressor parts A compressor has various components that enable it to perform its functions adequately. The compressor has several valves and other components (Carlos, 2012). After cooler This component is mainly or the purpose of removing moisture from the air. This is mainly achieved by lowering the temperature of the air. The cooler may be water based or air based. Airline lubricator This is an important component for lubrication of the equipment. It injects oil mist into the compressed air system. Automatic water valve This is used for the purpose of controlling the flow of water in the compressor. It is mainly found in water cooled compressors. It opens and closes automatically depending on the conditions required. Belt guards This component is found in a belt driven compressor. It is mandatory for the compressor to have this component. It guards the area where the fly wheel and motor pulley belts are exposed. This is mainly for the safety of the operator. Discharge line filter This component helps in the protection of the pneumatic tool and equipment connected to the compressor. It traps the foreign particles in the in the compressed airstreams. Dryers It is mainly designed to minimize the moisture in the compressed air system. Filters It is designed to trap foreign particles from entering compressed air system. This part is very vital and requires replacements after sometimes. It comes in various designs depending on the manufacturer. Manual and magnetic starters It provides thermal overload protection for motors. The local electric codes differ and should be used according to the manufacturer’s instructions. Moisture separator: Its main purpose is to trap and expel condensed moisture and oil in a compressed air system. The process may be manual or automatic depending on the manufacturer and the component itself. Pressure reducing valve: This device is adjustable and it is used to regulate the initial high pressures to a lower and constant secondary pressure which is required for running the compressor. Pressure relief valve: If pressure exceeds the specified upper limits. This valve is used to relief the compressor of the excess pressure. This component is adjustable and it can close once the required pressure is attained. Receiver: It is a component that stores the gas under pressure and it acts as the source of the pneumatic power. Its position is useful in determining whether it is referred to as wet or dry. This is the most important component of the receiver. The engine: This may be gas or electric. The electric engine is mainly used indoors where electricity is available. The gas engine is mainly used outdoes. However the selection of the engine depends on the size of the compressor and the task it is required to perform. All the components of the compressor are important. The failure of one component may result to the failure of the whole system or it may end up affecting the equipment used alongside the compressor. It is therefore impotent to check for trouble shooting and repair any component that exhibits problems. The routine maintenance and replacement of the components id a must this will ensure that the compressor works correctly for a long time. Types of compressors There are various types of compressors in the market. However the most common includes the rotary the centrifugal and the reciprocating compressors. Reciprocating compressor In this type of compressor, multiple cylinder arrangements are common. The piston is usually driven within the cylinder. The air sucked through the inlet in the suction stroke of the piston. It is then compressed and driven to another valve at the return stroke of the piston. This type of compressor is very common in the market and at the field. It is further divided into two depending on the number of pistons it has. The compression takes place on only one side of the piston in a single acting compressor. In the double acting type, the compression takes place on both sides of the piston. This affects the capacity of the piston and the type of work it may carry out. The reciprocating compressor is mainly used to supply small amounts of gas at a relatively high pressure. However the pressure can range in this type of compressor. It main source of power may be through an electric or a diesel driven engine. Its arrangement is simple and it is easy to operate,. However it requites frequent maintenance practices to keep it working and prevent any damage. Its efficiency can be assessed and it will be used depending on the output it has. Rotary compressor This type of compressor has simple arrangements. It is comprised of two rotating helical rotors. The rotors rotate and force gas to enter into a smaller space. Once the gas has entered, it cannot escape back. This made possible through a valve that prevents the air from escaping and it remains under pressure. Thos type of compressor has numerous advantages. It is able to produce a high output volume that can be used for operating large equipment. The compressor also produces a pulse free gas which is more reliable and useful. Its arrangement is simple but it requires high maintenance practices. It is able to use an electric engine to perform its operations. However, it can also be used for large scale operations with other equipment to produce good results. Centrifugal compressor This type of compressor is composed of an impeller rotating at a high speed. The impellers are usually mounted in a casing. Through the rotation of the impellers at high speed, the air is subjected to a form of pressure which makes it experience an out ward flow with high pressure being created at the center. This type of compressor is used to compress a high volume of air to moderate pressures. This is mainly due to the centrifugal action and force that is created when the rotation of the impeller occurs. The name centrifugal compressor is derived fro the actions of the compressor using the principle of centrifugal force. The advantage of this type of compressor is that it produces a smooth discharge of the compressed air. Different types of engines can be used to run this type of compressor. This includes the diesel and electric engines. It is efficient where a large volume of compressed air is required. Routine maintenance practice is required and the impellers may need replacement after sometimes. Assessment of the compressor and the compressed air system The working conditions of the compressor should always be assed in order to determine the performance and the working condition of the compressor (Denair Compressor Company, 2010). The analysis of the efficiency of the compressor should be carried out frequently and repairs should be done incase any problem is noted. The compressed air system should be assessed thoroughly since it is the most important part of the compressor. Compressed air system is composed of various distributions of pipes and valves. The main airline should always be larger than the compressor outlet. The piping should always be sloped towards the drain point. To prevent the moisture from entering the outlet, the branches should be connected to the top of the main. The system of valves, gauges and fittings are mainly for the purpose of ensuring the safety of the operator and the efficiency of the compressor and to prevent any leakages that may lead to poor performance. The tank contains a valve which is useful in preventing the levels of the gases to reach extremely high and dangerous positions. Some of the valves are usually automatic and will open and close depending on the condition of the pressure in the compressor. If the pressures are too high the engine is shut automatically due to the arrangement of the valves. Any leakage or impurities may cause a lot of Damage to the compressed air system. It is therefore advisable to check for any trouble shooting and repair any damages immediately. Capacity of compressors The capacity of the compressor is mainly dependent on the type of compressor and the functions it is supposed to perform. There various methods used to determine the capacity of compressors. Some may include mathematical formulas while others may include manual methods. The pressure required has to be calculated first or it should be established. The capacity of the air will be determined by the rate at which the compressor is able to suck in air. Compressor efficiency Efficiency of a compressor is the capacity of the compressor to utilize the compressed air into the tasks that the compressor has to perform there are several methods used to calculate the efficiency of the compressor however the power must be known so as to make substitutions in the formula and calculate the efficiency. The flow rate temperatures and pressures must also be known. However some of these factors are constants and are universally accepted. The following formula for power may also be used to calculate efficiency of the compressor. Part 2 (pump) Introduction A pump is a mechanical device that is used to move fluids. These fluids include liquid gases and slurries. The pump is able to achieve this through mechanical displacement of the fluids. The pump is usually connected to a source of power or an engine. Diesel engine can also be connected to a pump in order to run it. The pumps are usually classified into three major categories. This includes, direct lift pumps, displacement pumps and gravity pumps. This classification of pumps is dependant on the mode of fluid transmission (Karrasik 67). The pumps are also named according to the classes in which they belong. Pumps have a lot of uses in various engineering and construction field all over the world. The most important and common uses of a pump includes pumping water. This is usually done when the water cannot be move in large amounts to intended areas by use of pipes. A pump is thus used for this purpose. Energy will be injected to the water which will enable it to flow to the required destination. Other uses of pumps also include the pumping of sewage in the municipalities. Cement is also pumped into trucks using special pumps. The size and efficiency of the pump is usually determined by its function. This is mainly the head in which the pump is required to overcome in order to move the fluid to the required area. The paper will discuss various types of pumps, their efficiencies and other principles of pumps. A small, electrically powered pump Pumping systems The main purpose of a pumping system is to transfer liquids from one point to another. This is done trough an efficient pumping system. A pumping system is thus the components that are used to move the fluids from one point to another. This includes the pump, a prime mover and the pipes. Valves are used to control the flow of the liquid being pumped. The prime mover is the source of energy that runs the pump. This includes the engine. The engine can be run through the use of fuel like diesel and petrol. Electricity can also b\e used to run the pump. This is through the use of an electric motor. The pump itself has the mechanism of moving the fluid from one point to another. The pump is usually in contact with the fluid through various means like being submerged or use of a foot valve. Once the engine is started, the pump will star running and the fluid will be transferred. In most cases depending with the capacity of the tank, the pressure may be high on the pipeline which acts as the tool for transmitting the fluid. This requires that the pipe is able to withstand the pressure without bursting. The selection of the pipe is usually done depending on the expected pressures. Different pipes can withstand different mount of pressure. To control the flow of the fluid being pumped, valves are usually fitted along the pipelines. The valves have different functions which includes releasing the air from the pipeline shutting off the flow of water or controlling the flow rate of water in the pipeline. In order to have a good pumping system, the pump, the prime mover and the valves should be carefully selected. System specifications All the pumps are usually rated depending on their horsepower, flow rate, pressure and inlet suction. The suction is usually referred to as head; this is mainly the height at which the pump is required to raise the water at atmospheric level. This is dependant on the depth of the fluid for example water in a well or river. This an important factor to be considered when selecting a pump. If this is not considered then the pump may be unable to pump the water to the required height. It may also lead to cavitations of the pump due to sucking in air bubbles which damages the pump. The flow rate is the amount of fluid that is required to be transmitted per second. This is important when the fluid is being move to a storage tank. The flow rate will be important in determining the time it will take to fill the tank. The pressure on the other hand is the force that the fluid will require in order to be move to the desired destination. The pressure has to be determined so as to use the most appropriate pipe. This is to avoid the breakage of the pipe when the pressure is too high. It the pressure is too low, then the fluid will not flow. The horse power is the most important factor in pump specification. This is the output of the pump. In terms of fluid transmission it is usually the height at which the pump is able to pump the fluid. During the specification of a pump all these factors are always put into consideration in order to obtain the best results during pumping. Types of pumps Positive displacement pumps A positive displacement pump works by trapping a fixed amount of fluid before displacing it into a pipe which discharges the fluid. In most cases the fluid being moved by this kind of pipe is usually water. The pumps derive its name from the action it does which is displacing the water to the positive direction which is in the pipe. This cycle is usually repeated once the water has been displaced. The process takes place at a very high speed. The liquid flows into the pump as the cavity expands on the suction. However during the discharge the cavity collapses (Hill 87). These types of pumps are considered constant flow machine. This is mainly because the fluid flows at a constant rate despite the pressure involved. Changes in pressure may result to an increase in flow rate or decrease but it will still flow at a constant rate. The positive displacement pump can further be classified into three groups. This includes the rotary type, the reciprocating type and the linear type. They all function using the same principles but the components may be different. The rotary type operated through rotation which causes a vacuum that water is sucked into it. Its main advantage is the fact that it removes air from the line which in turns eliminates the need for bleeding. Its main disadvantage is that it requires frequent replacement of the parts which are easily eroded. The reciprocating pumps on the other hand cause the displacement of the fluid by use of oscillating pistons. They are mainly used for pumping high viscous fluids including heavy oil and concrete. Dynamic pump In this type of pumps, the kinetic energy is added in the fluid to increase the velocity of the fluid. These pumps uses the concept of the first law of thermodynamics which argues that energy cannot be created or destroyed, instead it is converted into a different form of energy. The pumps can further be subdivided depending on the form in which the velocity gain is achieved. The main advantage of the dynamic pump is that it has the ability to be operated under closed valve conditions without causing any failure. The dynamic pumps have three main characteristics. It utilizes the use of continuous energy which is being injected to the fluid. When the energy is added, it converts it to increase the kinetic energy which results to an increase in velocity. The velocity is then used to increase the pressure head. These types of pumps can be further classified as velocity pumps due to the fact that it utilizes the velocity in its operations. Centrifugal pumps. A centrifugal pump uses the rotating impeller to increase the pressure on the flow rate of the liquid. The centrifugal pumps are the most common types of pumps in use. This is especially in the transmission of less viscous liquids. In the water sector these types of pumps are most commonly used. The water enters the pump near the rotating axis and it is accelerated by the impeller. The water then flows radically outwards in the down stream piping chamber. The main advantage of this pump is that it can be used for a large discharge trough smaller heads. This makes it advantageous in most water supplies. The water can be pumped in large volumes fro a river to the piping system with a lot of ease. However the pump cannot be used where there is a deep well. This is because the pump may not be able to overcome the head which will cause inefficiencies and failure of the pump. This type of pump is mainly associated with radial type of flow. However due to the rotation of its impeller, it is named centrifugal. The impellers should be replaced as this type of pumps frequently experiences cavitations which lead to the erosion of the impellers (Hydraulic institute 101). This causes them to fail and produce rattling noise during their operations. Incase of such noise from the pump then it is a sign that cavitations has occurred. Centrifugal pumps can be used alongside diesel engines to pump water in rural areas where electricity is not available. However in areas where there is electricity, it can be connected to a motor which will also work properly. However it may consume a lot of power depending on the time of operation and the amount of water pumped. Assessment of pumps Assessment of pumps will help determine whether the pump operates correctly or not. This will give a chance to the operator to make corrections in areas which the pump is not performing. This includes conducting repairs or replacing the worn out parts. Various aspects of the pump have to be determined to ensure that it conforms to the manufactures specification. If there are any alterations then it means that the pump needs to be corrected. The pump capacity has to be determined to verify if the pump is still operating at the right capacity. The pump capacity is the volume of liquid that a pump delivers per unit time. The total head has to be determined to check on the work done by the pump. The total head includes static head, velocity head and friction head. The system resistance which is the sum of the total head and frictional head is also determined. If any problem is noted in the assessment then it means that the pump requires immediate repair. If the repairs are not done immediately, then the pump may end up failing completely which failing to work completely. This is more costly since the owner will be required to purchase another pump. The repairs should however be carried out by qualified technicians to avoid frequent breakdown or complete breakdown of the pump (Wasser 11). Energy efficiency in pumps The efficiency of the pump can be defined as the ration of the power transmitted to the fluid as compared to the power supplied to drive the pump. The efficiency of the pumps is not the same and it varies from one pump to another. The information about the efficiency of any pump is usually supplied by the manufacturer. The engineer carrying out the design will therefore recommend for the purchase of the pump depending on the efficiency. This will also determine the tasks the pump is able to perform. However, the efficiencies of most pumps will always decrease with time. This is mainly due to the wear and tear of the pump. With time the pump may wear out completely causing it to malfunction. However for the pump to operate for a longer period, then maintenance practices should be done frequently by a qualified technician. The pump efficiency is usually done through calculations. To calculate efficiency of a pump, the following needs to be determined, the horse power into the pump and the horse power out of the pump. The efficiency of ms pumps is closely related ton the shape of the impeller. Efficiency =Horse power out of the pump/ Horse power into the pump. Horsepower out of the pump= (Head* Capacity* Density) ÷ (time.) Works Cited Karassik, J. et al (2001). Pump Handbook (3rd ed.). New York: McGraw-Hill. Hill, D. (1996). A History of Engineering in Classical and Medieval Times. London: Routledge. p. 143. Retrieved on 5 March 2012 from http://books.google.com/books?id=MqSXc5sGZJUC&pg=PA143&dq=Taccola+first+pis ton Wasser, G. et al (1993). "Extended Life, Zero Emissions Seal for Process Pumps". Routledge. Welcome to the Hydraulic Institute. Pumps.org. Retrieved on 2012-03-05 Carlos, M. (2012) Parts of a compressor. Retrieved from http://www.ehow.com/list_7351972_parts-compressor.html#ixzz1oDrmvIuR on 5 March 2012 Shanghai DENAIR Compressor Co., Ltd, (2010). Overview about Air Compressor Transmission System Retrieved from http://www.denaircompressor.net/NewsShow.aspx?id=dc26c22b-4006-4e93-b10a- c99aae924006 Search the Engineering ToolBox (2012) Retrieved on 5 March 2012from http://www.engineeringtoolbox.com/air-compressor-types-d_441.html Read More