What is the big end of a connecting rod?
The big end of the connecting rod connects to the crankpin journal to provide a pivot point on the crankshaft. Connecting rods are produces as one piece or two-piece components. A rod cap is the removable section of a two-piece connecting rod that provides a bearing surface for the crankpin journal.
What are the 4 types of connecting rods assemblies?
There are essentially four types of connecting rods that most engine builders use – cast, forged, billet and powdered metal – in two basic styles: I-Beam and H-Beam.
What are the dimensions required to design connecting rod?
The literature review showed that there are three fundamental dimension to be take into account on a connecting rod design. These are; – Small end inner diameter, – Cross-section, – Big end inner diameter. These dimensions change with respect to type and properties of engine.
How do you size a connecting rod?
Measure the length of the metal between the end of the connecting rod and its inner diameter, taking the measurement as close to center of the rod end as possible. Perform this measurement on both ends, then add the numbers together. Add the total to the sum of the halved inner diameters.
What are big end journals?
For extra confusion, the connecting rod journals are abbreviated to rod journals and also commonly called crank pins , or big-end journals . The stroke of the piston will be twice the crank radius. The rear end of the crankshaft extends outside the crankcase and ends with a flywheel flange .
What are big end and main bearings?
Main Bearing – Located on the Crankshaft Main journals. Big End Bearing – Located at the ‘Big End’ of the Connecting Rod, where it connects to the Crankshaft.
What is a big end bearing?
Big End Bearing – Located at the ‘Big End’ of the Connecting Rod, where it connects to the Crankshaft. Flange Bearing/Thrust Washer – Located at the end or mid-way through the Crankshaft. Small End Bearing – Located at the ‘Small End’ of the Connecting Rod, where it connects to the Piston Gudgeon Pin.
Which formula is used in designing of connecting rod?
Rankine formula
A connecting rod is a machine member which is subjected to alternating direct compressive and tensile forces. Since the compressive forces are much higher than the tensile force, therefore the cross-section of the connecting rod is designed as a strut and the Rankine formula is used.
Which material is used for connecting rod?
The materials used for connecting rods widely vary, including carbon steel, iron base sintered metal, micro-alloyed steel, spheroidized graphite cast iron. In mass-produced automotive engines, the connecting rods are most usually made of steel.
Are longer connecting rods better?
Longer rods can improve rod stroke ratio, reducing thrust loading on the piston. Many racing engines use longer connecting rods to help reduce piston weight while having positive effects on torque curve shape and positioning and combustion efficiency. Longer rods typically require shorter, lighter pistons.
What was the size of the connecting rod?
There were two objectives for this initial design study. The first was to provide the largest possible big end bearing on the connecting rod while maintaining stock crankshaft stroke (4.250 inch); stock connecting rod length (7.500 inch) and not having the connecting rod big end interfere with the camshaft, inner walls of the crankcase, or oil pan.
What causes the big end of a connecting rod to become oval?
This is the load that stretches the connecting rod, causes the big end to become oval, and pulls at the fasteners. The acceleration load G expressed in g’s can be approximated at any crank angle from the following equation, which can be found in many handbooks.
What are the studs on a connecting rod?
Precision studs with dowel pin accuracy are threaded into the upper rod half to provide accurate cap alignment. Both ends of these studs are accessible on assembly, so a micrometer can be used to measure stretch, which is the preferred method of measuring fastener preload.
When does the tension load on a connecting rod occur?
Tension loads are due to piston acceleration. Maximum connecting rod tension loading occurs at TDC at the end of the exhaust stroke and beginning of intake stroke when the connecting rod has to stop and then change the direction of the piston (Crank angle at 0 or 360 degrees).