The cylinder head lies across the top of machined bores and is located above the engine block. They form combustion chambers in which the ignited charge burns to generate power. The gaskets assist the head to form airtight seals above cylinders to avoid compression leakage for effective combustion in an engine. Air and fuel mixture passage is controlled by the cylinder valves and at the appropriate instant on compression stroke, a spark is introduced to trigger the combustion process.
After combustion has taken place, exhaust gases are allowed to escape through the outlet valves. In a flathead engine, most mechanical parts are located in the block and the head is manufactured with less moving elements. This arrangement will make minor repairs easier since the mechanic will not have to dismantle many small sized components. Nevertheless, the design of air passages may make this member appear complicated especially if the designer wishes to introduce swirl in the incoming gases.
Overhead valves may have to be actuated by camshafts located just beneath the top cover. Within the heads, lie special passages commonly referred to as tracks through which fuel and air mixture flow to the inlet valves. Exhaust gases also find their way out through the tracts leading to the manifold. Water cooled systems have special galleries for circulating the coolant.
The flow of coolants in the high temperature zones helps in the regulation of engine heat for optimum performance. Cylinder heads in overhead designs have spark plugs and passages along with the tracks to enable good flow of inlet and exhaust gases. Opening and closing of the shutting mechanisms is actuated by rotary motion made by the camshaft. The motion of the camshaft is transmitted through push rods and rocker arms. The cam profiles are machined to conform to the required settings for valve clearances.
The heads must be strong and rigid enough to handle the intense pressure acting on them and distribute the forces uniformly through the block. The lubricating oil, combustion gases and coolant flow independently through three dimensional routes. In countries like Europe, cast iron heads are being replaced by aluminum since it has the advantage of high thermal conductivity, high tolerance and light weight.
Designers pay much attention to the heads and engine block production as they are key in the overall performance of the system. Their dimensions are used to specify products made in vehicle manufacturing companies. V engines require two heads with identical features although it is possible to come across an in-line unit with one head. Several heads design are available in the market due to the varying valve positions and the type of the combustion chamber.
Low power engines work comfortably with two valves although larger units require a number of them. With more openings, the spark plug could be centrally positioned in a combustion chamber. A centralized spark source will allow uniformity in the combustion of the induction charge.
The cylinder head design should help to improve the turbulence of air and fuel mixture and still prevent fuel droplets from settling on the conduit wall. Cylinder valves are vital in the engine and require to be oiled along with the rocker arm assembly. It is necessary for combustion to take place with a turbulent flow as it increases the mixing process and thus enhances uniform burning.
After combustion has taken place, exhaust gases are allowed to escape through the outlet valves. In a flathead engine, most mechanical parts are located in the block and the head is manufactured with less moving elements. This arrangement will make minor repairs easier since the mechanic will not have to dismantle many small sized components. Nevertheless, the design of air passages may make this member appear complicated especially if the designer wishes to introduce swirl in the incoming gases.
Overhead valves may have to be actuated by camshafts located just beneath the top cover. Within the heads, lie special passages commonly referred to as tracks through which fuel and air mixture flow to the inlet valves. Exhaust gases also find their way out through the tracts leading to the manifold. Water cooled systems have special galleries for circulating the coolant.
The flow of coolants in the high temperature zones helps in the regulation of engine heat for optimum performance. Cylinder heads in overhead designs have spark plugs and passages along with the tracks to enable good flow of inlet and exhaust gases. Opening and closing of the shutting mechanisms is actuated by rotary motion made by the camshaft. The motion of the camshaft is transmitted through push rods and rocker arms. The cam profiles are machined to conform to the required settings for valve clearances.
The heads must be strong and rigid enough to handle the intense pressure acting on them and distribute the forces uniformly through the block. The lubricating oil, combustion gases and coolant flow independently through three dimensional routes. In countries like Europe, cast iron heads are being replaced by aluminum since it has the advantage of high thermal conductivity, high tolerance and light weight.
Designers pay much attention to the heads and engine block production as they are key in the overall performance of the system. Their dimensions are used to specify products made in vehicle manufacturing companies. V engines require two heads with identical features although it is possible to come across an in-line unit with one head. Several heads design are available in the market due to the varying valve positions and the type of the combustion chamber.
Low power engines work comfortably with two valves although larger units require a number of them. With more openings, the spark plug could be centrally positioned in a combustion chamber. A centralized spark source will allow uniformity in the combustion of the induction charge.
The cylinder head design should help to improve the turbulence of air and fuel mixture and still prevent fuel droplets from settling on the conduit wall. Cylinder valves are vital in the engine and require to be oiled along with the rocker arm assembly. It is necessary for combustion to take place with a turbulent flow as it increases the mixing process and thus enhances uniform burning.
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