Crankshaft

Crankshaft

… 1. Crankshaft Power from the burnt gases in the combustion chamber is delivered to the crankshaft through the piston,piston pin and connecting rod.The crankshaft (fig.3.62) changes reciprocating motion of the piston in cylinder to the rotary motion of the flywheel.Conversion of motion is executed by use of the offset in the crankshaft.Each offset part […]

Crankshaft Servicing

… 1. Condition. The crankshaft is one of the most highly stressed engine components. The stress increases four times as the engine speed doubles. The crankshaft is rejected if there is any sign of a crack, because a cracked crankshaft may break (Fig. 20.57) if continues in service. Crankshaft cracks in high production passenger car […]

Crankshaft Lubrication

… 1. Crankshaft Oil-hole Drillings Oil from the main oil gallery reaches each individual main-journal and bearing. Oil is fed through a central circumferential groove in the bearing and it completely surrounds the central region of the journal surface. Diagonal oil hole drills are provided in the crankshaft which pass through the webs between the […]

Crankshaft Materials

… Crankshafts materials should be readily shaped, machined and heat-treated, and have adequate strength, toughness, hardness, and high fatigue strength. The crankshaft are manufactured from steel either by forging or casting. The main bearing and connecting rod bearing liners are made of babbitt, a tin and lead alloy. Forged crankshafts are stronger than the cast […]

Crankshaft Counterbalance Weights

… Crankshafts normally have either integral (Fig. 3.63) or attachable (Fig. 3.64) counterweights. These counterweights counteract the centrifugal force created by each individual crankpin and its webs as the whole crankshaft is rotated about the main-journal axis. In absence of the counterweights, the crankpin masses tend to bend and distort the crankshaft causing excessive edge-loading […]

Crankshaft Design Considerations and Proportional Dimensions

… The present design consideration is to increase the stiffness of the crankshaft and reduce its overall length by incorporating narrow journals of large diameter. For the required wall thickness and coolant passages, the minimum cylinder centers can be around 1.2 times the cylinder bore diameter for an engine having its stroke equal to the […]

Crankshaft Nomenclature

… Crank-throw. This is the distance from the main-journal centers to the big-end-journal centers. It is the amount the cranked arms are offset from the center of rotation of the crankshaft. A small crank-throw reduces both the crankshaft turning-effort and the distance the piston moves between the dead centers. A large crank-throw increases both the […]

Crankshaft Working

Crankshaft Working Power from the burnt gases in the combustion chamber is delivered to the crankshaft through the piston,piston pin and connecting rod.The crankshaft (fig.3.62) changes reciprocating motion of the piston in cylinder to the rotary motion of the flywheel.Conversion of motion is executed by use of the offset in the crankshaft.Each offset part of […]