Piston Rings And Cylinder Liner: Working, Functions, And Maintenance

Piston Rings: Working and Importance

Discuss about the Development of Tribological Test Equipment.

The Piston rings and cylinder linear comprise a major part of a number of devices. The Cylinder linear is a major part of the engines and therefore hold an important functional value. This cylindrical part is fitted into the part of an engine in order to form a shape that represents a cylinder. The cylinder linear is an important part of the engine and comprises the internal part of the engine. The cylinder linear is an integral part of the engine, which is largely responsible for the working of the engine. The piston ring on the other hand are present in between the cylinder and the piston. The piston ring is responsible for allowing the engine to work in an efficient manner (Zhang et al., 2017). This is also another integral part of the engine and comprises an important part. Since both these parts comprise an important part of the engine, care should be taken that the parts are not affected due to the various wearing and tearing processes. The coating mechanism can be used in order to prevent this wear and tear of the parts. The surface treatment is another way in which the friction and the wear and tear can be reduced. If these parts are affected then the whole engine may be affected (Tas et al., 2017). As a result of which the protection of these parts have become an integral aim of the various organizations. The report introduces the various working concepts of the engine and how the piston ring and the cylinder linear contributes in the working of the engine. The report also states the various problems that are present in these parts of the engine and how these affect the engine independently. The solutions of how these can be overcome is also presented in the report.

The piston rings are present in between the cylinder and the piston and forms an integral part of the engine. The Piston ring was invented by John Ramsbottom in the year 1854. It soon replaced the devices that were earlier used in the various engines. The Piston rings had grabbed the focus and development have been taking place in this area (Shahmohamadi et al., 2015). The Piston rings amount for a high percentage of friction, around twenty four percent. The friction is of high amount as the friction has been compromised for obtaining a design with good sealing capability and a long lifetime durability. These featured contribute in increasing the friction in the engine.

There are various functions that are performed by the piston rings due to which these rings are considered as an integral part of the engine. The first function that is performed by the piston ring is that the piston ring is responsible for maintain the gas compression level between the piston and the cylinder. The piston rings places itself in between the cylinder and the piston and helps in maintaining the gas compression among these devices (Shen & Khonsari, 2016). This function is considered as important since if this compression does not take place in a proper manner then the engine would not be able to produce the output that the engine is supposed to produce.

Functions of Piston Rings

The piston rings face friction each time the gas is ignited. As a result of which the friction between the metals increase. To reduce this effect a small amount of oil is poured onto the piston. The piston ring adjusts the amount of oil that is being poured.

As the piston ring is present in between the cylinder and the piston, the heat transfer can take place in between cylinder and the piston. The cylinder may get heated to a large extent and then the heat can be transferred to the piston (Ober et al., 2016). The other case is also possible that if the piston gets heated to a large extent then the heat of the piston can be transferred to the cylinder. Thus, the piston rings helps in reducing the heat, which if accumulated in the piston can damage the engine. As the temperature of the piston may reach as high as 300 degrees, the accumulation of this temperature is harmful for the engine and can damage it. Thus, the piston rings are used in order to bring down this temperature.

The cylinder linear is another important part which plays an important role in the proper function of the engine. The cylinder linear is a cylindrical shape device that fits into the body of the engine. The cylinder linear is a cylindrical shell, which is hollow in nature and it acts as an enclosure for the combustion to take place. The cylinder is hollow in nature but it has a high strength as the cylinder is always under fluid pressure because of the combustion that is taking place. The cylinder linear is responsible for withstanding high levels of pressure and stress. The cylinder linear has high temperature difference on the inside and the outside (Wolff, 2016). The cylinder liner has to withstand this high thermal pressure. Thus, the above facts show that the cylinder linear is responsible for keeping the engine protected from the wear and tear and the various changing conditions. The cylinder linear is thick and is made of strong materials so that the device can withstand high pressure (Söderfjäll, Almqvist & Larsson, 2016). Mostly the material that is used in the making of the cylinder linear is cast iron because of the fact that cast iron is able to stand pressure and the changing conditions. The cast iron is porous in nature due to which there is minimum risk of piston seizure.

The cylinder linear is also an important device that helps in performing of the various important tasks. The first function of the cylinder linear is that it serves as the sliding surface and forms the inner wall of the cylinder (Tomanik et al., 2018). The cylinder linear consumes lower lubricant and performs its function in an efficient manner. The cylinder linear does not have high amount of wearing and tearing itself. The cylinder linear also contributes in the lesser wearing of the piston rings also, which are present alongside the cylinder linear. The cylinder ring is responsible for the receiving of the heat of the piston through the piston ring. The cylinder linear is responsible for passage of the combustion heat to the coolant for keeping the system cool. The cylinder linear is also helpful for the prevention of the escaping of the compressed and the combustion gas from the system. This is an important function as the escape of the gases may cause drastic result such as causing of explosion.

Importance of Cylinder Liner

The cylinder linear also uses cast iron material since the life of the engines of the various vehicles should be high enough. The cylinder linear has to be at high resistant to wear since there are various processes that are involved in the engine (Hubert et al., 2014). The cylinder wall is at high temperature and the piston and the piston rings slide at high speed. All these activities may result in the wearing of the various parts of the engine.

The part of any device that faces maximum exposure is the surface of the device. Thus, the surface has the maximum possibility of being open to wearing and tearing. The surface irregularities may often play a role in lowering the performance of any device (Zavos & Nikolakopoulos, 2015). Thus, the irregularities of the surface have to be removed. The various factors that result in the causing of the surface irregularities are:

The friction is the most common cause of the wearing away of the surface. Friction is present in all the machines and cannot be avoided. Friction can be reduced by following some processes but it cannot be removed completely (Zabala et al., 2017). Some friction always pertains. Friction can be referred to as negative acceleration and it acts in the opposite direction to that of acceleration of the body. The movement of the part of the machine takes place in one place while the   negative acceleration or friction takes occurs in the opposite direction. The friction is a form of force, which acts on the body in the opposite direction to the application of the force of the device. This continuous force in the opposite direction will cause the device parts to eventually break off and corrode.

There are two forms of friction, the first being static friction and the other type being kinetic friction. The static friction as the name suggests involve the operation between the two surfaces that are not moving with respect to each other (Peng, Wang & Zou, 2015). The other form of friction is the kinetic friction, which is the friction existing among objects that are in motion. The friction can take place in not only solids but also in liquids and gases. There may be friction in the atoms that are present in the solids as well. The friction in the liquid is known as viscosity. There is also important aspect of friction such as due to friction between two bodies heat is produced.

The use of the type of lubricating material is also another factor that contributes to the surface irregularities. Friction is used in order to remove the various surface irregularities that are present in the engine. However, the use of the incorrect lubricants may contribute in the surface irregularities (Rahmani et al., 2017). The correct usage of lubricants can positively contribute to the reduction of the friction in the engine. The usage of the wrong lubricant often result in the corroding away of the surface to a large extent.

Functions of Cylinder Liner

Galling is a form of wear that is caused by the surfaces that are sliding in nature. Galling occurs due to the adhesion among these sliding surfaces. The galling process is the combination of the friction and the adhesion factors that is occurring in between the surfaces. The effect of the galling process is drastic that is it may cause the breakage of the crystal structure that lies under the surface of the structure (Harsha, Limaye, Tyagi & Gupta, 2016). The problem that the process of galling causes is that some of the material may get stuck up to the adjacent surface. This will bring down the performance of the device and the engine as a whole. Galling generally occurs in the metal surfaces that slide over each other. Galling occurs when there the lubrication is not done as per the requirement. The occurrence of galling process may also depend on the crystal structure of the material that is given.

Surface fatigue is another reason which is another cause for the wearing away of the surface and the reason for the cause of the other forms of surface irregularities. The surface fatigue may take place due to the cyclic loading. The surface fatigue form is different from the other types of fatigue (Özkan et al., 2015). If the surface fatigue is not addressed then the failure can spread through the surface of the material. The surface fatigue occurs in the top layer of the material (Grabon et al., 2018). The surface fatigue generally appears in the form of macrocrack on the surface of the material. There can be a number of causes of the surface fatigue such as the repeated shear stress. Stress is put on the materials by the various forms of processes. The surface fatigue may take place as a result of the wear that is been caused by the oscillating contact present among two members of the material. Surface fatigue may take place more in devices that get insufficient amount of lubrication and also those having rough edges. The piston ring has to face a number of stress factors such as that of the piston and the cylinder linear. The cylinder linear faces a thermal stress, which arises due to the difference in temperature in the inside and outside of the cylinder linear. Due to these continuous stress the surface fatigue may take place.

 The piston ring and the cylinder linear play a vital role in the working of the engine. Therefore, steps must be taken in order to ensure that the piston rings and the cylinder linear are working in a proper condition. The main form of procedure that is used is coating. Coating procedure involves the addition of a new layer that reduces the surface irregularities. Coating involves the application a coat of  aluminum on the surface of  the material (Aboulkhair et al., 2016). The aluminum coat is produced by baking the aluminum coated coil along with polyster, acrylic and other such materials.  The process of coating can be used for reduction of friction by a considerable amount by the application of the lubricant (Kumari, 2017). The application of the coat can help in the reduction of the friction. The application of coat helps in the reduction of the negative acceleration and the reduction of the force. Application of the lubricant helps in the reduction of the magnitude of the force which is being applied in the negative direction of the application of force. Polishing of the rough surfaces can also contribute in the reduction of the friction of the surfaces. This is another way in which the surface irregularities can be removed. The distance between the surface contacts should also be large enough in order to reduce the magnitude of friction. The reduction of the forces that is acting on the surface of the device can also contribute considerably in the reduction of the friction and as a result reducing the level of surface irregularities. The using of the ball bearing can be the other strategy that can contribute in the reduction of the friction.

Maintenance of Piston Rings and Cylinder Liner

Nickel plating is also necessary for the reduction of the surface irregularities. The use of Nickel- Ceramic coat does not cause the surface to corrode and cause irregularities of the surface. The galling may take place during the manufacturing process. To avoid the galling process that is occurring during the manufacturing process is by coating the wires with copper material (Dunne et al., 2017). The other method that can be used in order to minimize or prevent galling is by using the coat. The use of Nickel- Ceramic coat should be done by the use of metal to metal contact.

For the reduction of surface fatigue the use of Diamond Layer coating should be made and the use of materials with high toughness and slow crack growth. Materials having higher resistance to corrosion  can be used in order to prevent the surface fatigue. The reduction of the manufacturing errors should also be done in order to reduce the surface fatigue that is occurring during the manufacturing procedure (Arabzadeh et al, 2016). There should be a proper check on the joins specially, the double sheer joins and the other joins that have a chance of facing high pressure. There should be enough resistant provided to corrosion due to the reduction of surface fatigue. Since there is a large temperature difference in the internal and the external of the cylinder, the materials that should be used should not be varying in temperature (Morales, Boffy & Venner, 2017). The materials that are used should also be resistant to UV light in order to get rid of this form of surface irregularity

Conclusion:

From the above report it can be concluded that the piston ring and cylinder linear form an integral part of the engine and the proper working of the engine generally depends on the working of these device independently. The piston ring is responsible for improving the performance of the engine as a whole. The piston ring helps in making the engine work in an efficient manner. The piston ring is present in between the piston and the cylinder and as a result is also responsible for the transfer of heat from the piston to the cylinder. The piston ring helps in the withstanding the high pressure that may occur due to the various changing factors in the engine. The cylinder linear on the other hand is responsible for the withstanding of the high amount of pressure and drastic temperature conditions that are taking place within the engine. The cylinder linear serves as the protection material for the engine. The damage to the cylinder linear may often cause damage to the engine. The piston- cylinder system combination comprise the maximum part of the engine and is responsible for the working of the engine in an efficient manner. Every devices face drawback and the piston- cylinder system also faces drawbacks. The drawbacks are caused due to the various factors. Since the surface is most open to irregularities, the maximum wear and tear take place in the surface. Due to the effects on the surface, the performance of the device is also compromised. There are certain techniques that can be applied for the improvement of the performance of the machine and getting rid of the problems that persist. Development has been made in the field of piston rings and cylinder linear research for the improvement of the performance and getting improved performance from the engine.

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