3069576 Original Excavator Hydraulic Pump Link Fork for EX200-5

Part number 3069576 is the original hydraulic pump connecting rod fork (also known as crosshead/connecting fork) provided by Hitachi Construction Machinery for the EX200-5 series 20 ton hydraulic excavator. This component is mainly used inside the plunger pump to convert the rotational motion of the crankshaft into the reciprocating motion of the plunger, and is the core joint for power transmission in hydraulic pumps. Its universal models cover 20 ton models such as Hitachi EX200-2, EX200-3, EX200-5, as well as some equivalent platform excavators such as ZX200-5 and ZX200-6. As an original high-precision transmission component, its size, heat treatment process, and precise matching with the pump body crankshaft hole, plunger ball socket are strictly prohibited from using non-standard spare parts to avoid abnormal noise, insufficient pressure, or stuck plunger inside the pump.

This product is an original forged steel connecting rod fork, usually made of 20CrMnTi or 42CrMo material, which has been quenched and tempered with carburizing and quenching treatment. Typical technical parameters: total length of approximately 80-120mm, fork width of 20-30mm, pin hole diameter of 10-15mm, working load ≤ 50kN, surface hardness HRC58-62, core hardness HRC28-32. The fork body adopts a symmetrical Y-shaped structure, with wear-resistant copper sleeves or needle roller bearings at both ends, forming a low friction pair with the crankshaft pin and plunger ball head. Its dynamic balance accuracy is ≤ 0.5g · mm, in compliance with JIS B 2005, GB/T 3077 and other standards, and can maintain a gap of ≤ 0.05mm under high-speed reciprocating motion (frequency ≤ 30Hz).

Disassembly inspection: Before replacement, the hydraulic system pressure must be released and the outside of the pump body must be cleaned. After disassembling the pump body, check the connecting rod fork for cracks, deformation, and wear, measure the diameter of the pin hole (allowable wear ≤ 0.10mm) and the symmetry of the fork (tolerance ± 0.02mm). Installation points: 1 Dip the new connecting rod fork into hydraulic oil for pre lubrication; 2. Ensure that the crankshaft pin is aligned with the fork hole, gently push it to position by hand, and avoid knocking during installation; 3. Tighten the fixing bolts step by step in a cross sequence (usually with a torque of 60-80N · m); 4. After installation, manually rotate the crankshaft several times to check whether the movement is smooth and whether there is any jamming. Run test: After assembly, start the engine and idle for 15 minutes, monitor for any abnormal knocking sounds in the pump, and check if the system pressure is stable.