CAT 159-5728 BUSH-HITCH

CAT 159-5728 is a Caterpillar genuine induction-hardened steel fixed articulation bushing (non-rotating, compatible with skid steer loaders/mini excavators boom and bucket connection pins). Its core function is to provide articulation support between the boom and chassis, and between the bucket and boom. It absorbs impact loads and reduces wear on pins and pin holes. It is compatible with the boom/bucket articulation points of Cat 216B3/226B3 skid steer loaders and 303.5E2 mini excavators. The following is professional structured information:

Core Technical Parameters (Professional Version)

Item Details
Basic Attributes
Model: 159-5728, Type: Induction-hardened steel fixed articulation bushing (non-rotating, compatible with pin-fixed support), Compatible with Cat 216B3/226B3 skid steer loaders, 303.5E2 mini excavators boom and chassis articulation pins (pin diameter φ32 mm), bucket and boom connection pins, Material: 4140 Alloy steel (induction hardened, surface hardness HRC 58-62, core hardness HRC 30-35), inner diameter φ32 mm, outer diameter φ42 mm, total length 45 mm, single weight approximately 0.22 kg, rated load capacity 300 MPa, operating temperature -40℃ to +150℃, compatible pin tolerance f7, compatible pin hole tolerance H8, suitable for medium-load articulated applications with a swing angle ≤±15°.

Key dimensions: Inner diameter tolerance 0/-0.015 mm, outer diameter tolerance +0.020/-0.010 mm, length tolerance ±0.1 mm, hardened layer depth 2.0-2.5 mm, chamfer at both ends 1.0×45°, coaxiality ≤0.03 mm, compatible pin radial clearance 0.025-0.035 mm, pin hole interference 0.015-0.020 mm. mm
Material and Process: 4140 alloy steel (containing chromium and molybdenum, good hardenability), surface induction hardening (depth 2.0-2.5 mm, hardness HRC 58-62), core tempering (hardness HRC 30-35, good toughness), surface finishing (roughness Ra≤0.8 μm), deburring at both ends, compatible grease is Cat Moly Grease Plus (lithium-based extreme pressure grease, NLGI 2 grade)

Compatible Models: Cat 216B3/226B3 skid steer loaders (serial number JJP1000-UP), 303.5E2 mini excavators (serial number JFR1000-UP), used for fixing and supporting the boom and frame hinge point, bucket and boom connecting pin, compatible with φ32 mm pin, installed in the pin hole of the boom/frame/bucket, mates with dust ring/sealing ring

Assembly Fit: Interference fit with pin hole (interference amount) 0.015-0.020 mm), clearance fit with the pin shaft (clearance 0.025-0.035 mm), rear end face runout ≤0.05 mm, no jamming during oscillation, radial runout ≤0.1 mm, fitting pin hole inner diameter ≥42 mm, depth ≥45 mm.

Installation and Maintenance Points: Before installation, clean the pin hole and check for bushing deformation/fraying of the hardened layer. Use the cold fitting method (press the bushing into the tooling) to smoothly press the bushing in. Do not strike the bushing end face to prevent damage to the hardened layer.

After installation, add Cat Moly Grease Plus grease, replenishing every 500 hours. Replace immediately if the bushing inner diameter wear >0.15 mm or surface cracks appear.

Maintenance Recommendations: Avoid use under unlubricated conditions to prevent dry friction from causing the bushing to stick to the pin shaft. Regularly check the dust seal to prevent impurities from entering the pin hole and accelerating wear.