358-7876: 25mm Outer Diameter Flange Sleeve Spacer

Cat 358-7876 is a Caterpillar single-ring sealing flange sleeve gasket, suitable for flange connections in hydraulic lines of construction machinery, engine fuel/oil lines, transmission oil lines, etc., for sealing and leak prevention, and withstanding high pressure and vibration conditions. The following are the core parameters and application points:

Core Parameters (Precise and Authoritative Version)

Item Details
Basic Information
Model 358-7876, type is single-ring rubber-coated metal core flange sleeve gasket (with locating ring), suitable for Cat 320GC/336D/349D excavators, 950M loaders, C9.3/C13 engines, 420F2 backhoe loaders, etc., used for hydraulic pump outlet flanges, engine oil cooler flanges, transmission input shaft flanges, drive axle oil line flanges, etc. Sealing media include hydraulic oil, engine oil, diesel, coolant, etc.

Compatible Models
Compatible Cat This product is suitable for 320GC/323GC/330D/336D/345D/349D excavators, 950M/962M loaders, C9/C9.3/C13 engines, 420F2/430F2 backhoe loaders, D5/D6 bulldozers, 299D3 skid steer loaders, etc., and is commonly used for hydraulic pipeline flanges, fuel injection system flanges, oil filter base flanges, and gearbox housing flanges.

Material and Manufacturing Process: The metal core is made of low-carbon steel (Q235), with a galvanized passivation surface for corrosion protection; the outer layer is made of nitrile rubber (NBR), which is oil-resistant and temperature resistant from -40℃ to 120℃, with a Shore A hardness of 70±5; the locating ring is made of nylon 66, which is high-strength and wear-resistant, ensuring that the gasket installation coaxiality is ≤0.05mm; the entire piece undergoes a molding and vulcanization process, with a rubber-metal core bond strength ≥1.5MPa, free from delamination and bubble defects.

Key Dimensions Outer diameter 25mm, inner diameter 15mm, thickness 3mm, locating ring diameter 22mm, locating ring height 1mm, compatible flange bolt hole center distance 32mm, bolt size M8×1.25, weight approximately 0.005kg, working pressure ≤35MPa, burst pressure ≥105MPa, sealing class ISO 15552, suitable for flange connections with an outer diameter of 15mm (DN15).

Matching components: Compatible with Cat 10-9275 extreme pressure lithium-based grease (apply to flange surface before installation), Cat 8T-8730 torque wrench (bolt torque value 18-22N・m), and matching flange gasket installation tool (Cat). 4C-4852 ensures uniform gasket compression and a good seal.

Function, Installation, and Maintenance Points

Core Functions: The metal core provides rigid support, the rubber coating provides a leak-proof seal, and the positioning ring ensures precise installation. It can withstand high pressure (≤35MPa), vibration, and temperature fluctuations, preventing leakage of hydraulic oil, engine oil, and other media. It is suitable for harsh working conditions in engineering machinery and improves the reliability of pipeline systems.

Installation Points: The flange surface must be clean and free of scratches and burrs. Align the gasket positioning ring with the flange positioning hole, tighten the bolts diagonally and evenly, with a torque value of 18-22 N·m, avoiding local overpressure that could damage the rubber layer. The installation ambient temperature should be between -20℃ and 40℃. Do not heat the gasket with an open flame.

Maintenance Points: Check the flange connection for leaks every 200 hours, and replace the gasket every 500 hours. If the rubber layer cracks, the metal core corrodes, or the positioning ring is damaged, replace it immediately to prevent seal failure and equipment malfunction.