Connecting rods are the backbone of an engine, and their life begins with a precise casting process that turns alloy into a reliable bridge between piston and crankshaft. In casting, every gram and every bend matters, because fatigue life begins with the microstructure formed in the mold.
Alloy selection and design follow the weight, stiffness, and heat-load requirements of the target engine. Common choices include ductile iron, compacted graphite iron, and steel. The goal is a balance of strength, toughness, and machinability.
From here, the pattern or mold is prepared. In sand casting, a pattern creates a cavity in silica sand with risers and gates sized to control shrinkage and flow. For higher accuracy or complex geometry, investment casting or lost-foam can offer superior surface finish and dimensional stability.
Melting begins in an induction furnace, with strict temperature control to ensure the alloy pours as a uniform liquid. Molten metal is poured into the mold under controlled pressure, and fluxes help reduce oxides. After solidification, a rough casting—called the as-cast blank—emerges, ready for cleaning and inspection.
Heat treatment is the hinge of performance. Normalizing or quenching and tempering tune the grain structure for fatigue resistance. Shot peening imparts surface compressive stresses that slow crack initiation. Non-destructive testing, such as magnetic particle or dye-penetrant inspection, screens for hidden flaws before parts leave the line.
Machining then converts the casting into a precise component. Bores, bearing fits, and thread forms are machined to tight tolerances, followed by surface finishing to reduce wear. Final inspection confirms that every rod meets the engineer’s specifications and the engine’s endurance needs.
The advantage of casting lies in cost efficiency at high volumes, design flexibility, and the ability to integrate features that reduce weight without sacrificing strength. Proper gating, risering, and process control minimize porosity and shrinkage, delivering consistent quality batch after batch.
If you’re designing the next generation of engines, partner with us early—from alloy choice to final finishing. We provide engineering support, material options, simulation, and rigorous QA, plus scalable production to meet your schedule. Contact us for a pilot run or sample parts and discover how casting-driven connecting rods can accelerate your engine program.
As a reliable supplier and partner, Oujia focuses on various engine partsengine parts, especially on gasoline engine parts and on diesel parts for passenger cars. Oujia not only provides high and stable quality and excellent services to our customers, but also provides long-term self- brand creation and OEM services for our overseas customers.
