CAT 281-7195 Left Hand Inner Insert

CAT 281-7195 is a left-side internal insert for Caterpillar mini excavators/loaders, commonly used for hinge pin holes in buckets, booms, or connecting rods. It is paired with 281-7196 (right-side external insert) and provides wear-resistant support, positioning, and anti-loosening functions. The following is the structured core information:

Core Parameters
Item Details
Basic Attributes
Model 281-7195, Left-side internal positioning insert, suitable for heavy-duty hinged parts, providing radial positioning and wear-resistant protection. It has no oil grooves/holes and is installed via press-fit/transition fit. It forms a precise fit with pins and bearing housing holes to reduce impact wear.

Compatible Models
CAT 305/306/307 excavators, 906/907/908 mini loaders, suitable for left-side internal holes in boom-stick hinges, lower hinges of the lifting cylinder, and frame connecting rod joints.

Material and Manufacturing Process Medium carbon steel (45#) base material, surface hardened, hardness HRC 45-50, wear-resistant layer thickness 0.8-1.2mm, surface roughness Ra 0.8μm, dimensional tolerance GB/T 1804-m

Key Dimensions: Inner diameter 60mm (2.362in), outer diameter 70mm (2.756in), length 50mm (1.969in), wall thickness 5mm, single-sided chamfer 1×45°, weight approx. 0.68kg

Functional Parameters: Radial load ≤80MPa, operating temperature -30℃ to 120℃, suitable for mineral oil lubrication, paired with 281-7196, ensuring hinge clearance 0.05-0.10mm

Matching Components: Matching pin diameter 60mm, matching bearing housing inner diameter 70H7, matching right-side external insert 281-7196, matching retaining ring 105-2345, Mounting Bolt 8T-4120
Installation and Maintenance Points
**Preparation Before Installation:** Clean the bearing housing hole and insert surface, removing burrs, oil, and rust; check the hole roundness to ≤0.02mm, and control the interference fit between the insert outer diameter and the hole to 0.015-0.03mm to avoid excessive interference causing insert deformation.

Pressure Pressing Steps: Press vertically and smoothly into the insert using a dedicated pressure tool, avoiding skewing; after pressure pressing, check the end face flatness to ≤0.03mm and the coaxiality with the right-side insert 281-7196 to ≤0.05mm; apply lithium-based grease before installing the pin to ensure sufficient lubrication of the mating surfaces.

Maintenance and Replacement: Check for insert wear and loosening every 500 hours. Replace the insert if the inner diameter wear exceeds 0.15mm or if surface cracks/peeling appear; avoid dry friction and overload impact, and regularly tighten surrounding bolts to prevent insert displacement.