Technical Upgrade in Excavator Power Systems: High-Strength Connecting Rods for Kobelco SK200 & SK350
both structural linkage components and engine internal parts plays a decisive role in overall machine performance.
Apr 24,2026
In modern excavation and construction operations, the reliability of both structural linkage components and engine internal parts plays a decisive role in overall machine performance. For Kobelco SK200 and SK350 excavators, two critical systems—the working equipment linkage system and the engine power transmission system—both rely heavily on high-strength connecting rod components.
From a technical perspective, connecting rods in excavators can be divided into two key categories: the bucket linkage rod (H-link) in the working equipment system, and the engine connecting rod inside the power unit. Although their functions differ, both are responsible for force transmission under high load conditions, and both directly influence operational stability and service life.
Working Equipment: Bucket Link Rod (H-Link)
In the SK200 and SK350 working equipment systems, the bucket link rod serves as a central structural component connecting the arm, bucket, and hydraulic cylinder. It ensures stable digging force transmission during continuous earthmoving and heavy-duty operations.
The high-strength excavator bucket link rod is manufactured using 50Mn or Q345B alloy steel, providing excellent structural durability under impact loads. Through hot rolling and precision machining, the component achieves stable dimensional accuracy, ensuring proper fit with OEM configurations.
To improve wear resistance, the surface hardness is controlled within HRC 45–58, with a hardened layer depth of 8–12 mm. This significantly reduces deformation and surface fatigue during long-term operation. In addition, the integration of ductile cast iron inner bushings provides self-lubricating performance, helping to reduce friction between pins and bushings.
For SK200-6, SK200-8, SK350-6, and SK350-8 models, this type of reinforced linkage structure helps maintain stable bucket motion and reduces maintenance frequency in demanding environments such as mining and quarrying.
Engine System: Precision Connecting Rod
In the engine system of Kobelco SK200 and SK350 excavators, the connecting rod plays a fundamental role in power conversion. It links the piston and crankshaft, converting reciprocating piston motion into continuous rotational output.
The engine connecting rod used in SK200 (Hino J05E) and SK350 (Hino J08E) engines is manufactured from high-strength forged alloy steel. The forging process enhances internal grain structure, significantly improving fatigue resistance and impact strength under high combustion pressure.
Each connecting rod undergoes precision machining and dynamic balance calibration to ensure stable operation at high RPM. The I-beam structural design provides an optimal balance between strength and weight, improving engine efficiency while maintaining durability.
These specifications make it suitable for engine overhaul applications, ensuring OEM-level dimensional compatibility and reliable installation performance for SK200-8 and SK350-8 models.
Technical Summary
Although the bucket link rod and engine connecting rod operate in different systems, both are essential to the overall performance of Kobelco SK200 and SK350 excavators. One ensures stable mechanical force transmission in the working equipment, while the other guarantees consistent power output within the engine system.
By improving material strength, machining accuracy, and wear resistance, these connecting rod components contribute directly to longer service life, reduced downtime, and improved operational efficiency in heavy-duty working environments.
For operators working in earthmoving, mining, and construction industries, selecting high-quality connecting rods is a key factor in maintaining machine reliability and maximizing equipment productivity.
PREVIOUS:
Related Posts
both structural linkage components and engine internal parts plays a decisive role in overall machine performance.
DH220 Drive Sprocket Ring Gear
This DH220 Drive Sprocket Ring Gear is a high-performance undercarriage component, precision-engineered for Doosan/Daewoo DH220 series excavators. It serves as the core driving part of the crawler system, efficiently transferring power to the track chain for reliable machine propulsion.