CAT 374-6512 BEARING-SLV-GD

CAT 374-6512 (YM, Yellowmark) is a hydraulic seal retainer ring (also known as an anti-extrusion retainer ring/support ring) for Caterpillar engineering machinery. It is often used in conjunction with O-rings in high-pressure hydraulic cylinders, pumps, valves, or pipeline joints. Its core function is to prevent the seal from being squeezed into the gap under high pressure, protecting the seal and improving its pressure resistance. The following is precise technical and application information:

Core Technical Parameters
Item Details
Part Model: CAT 374-6512 (3746512) seal retainer ring, YM is Caterpillar Yellowmark series, suitable for high-pressure sealing systems, often used in conjunction with O-rings

Core Material: Polytetrafluoroethylene (PTFE) + bronze powder filler modification, oil and chemical corrosion resistant, operating temperature -30℃ to +200℃, Shore hardness D 75–85, compressive strength ≥100 MPa

Key Dimensions: Inner diameter 63.5 mm, outer diameter 71.44 mm, thickness 2.39 mm mm, free-state diameter tolerance ±0.15 mm, single weight approximately 0.02 kg (0.044 lb)

Suitable Operating Conditions: Suitable for static/dynamic sealing surfaces in hydraulic systems with pressure ≤40 MPa (400 bar), preventing O-ring extrusion failure; compatible with mineral oil, synthetic hydraulic oil, and other media.

Compatible Machine Models: CAT 320GC/323GC excavators (boom/stick cylinders), 966M/972M loaders (hydraulic pump/distribution valve), CS66B road rollers (travel hydraulic circuit)

Matching Seals: Compatible with O-rings with an inner diameter of 63.5 mm and a cross-sectional diameter of 3.53 mm (e.g., 1L-6388), used in cylinder pistons/cylinders, flange joints, etc.

Core Functions and Structural Features:

Anti-extrusion Protection: Filled with modified PTFE material for high rigidity, preventing the O-ring from being squeezed into the sealing gap under high pressure, avoiding shear damage to the seal; suitable for high-pressure hydraulic systems.

Temperature and oil resistant: Compatible with commonly used hydraulic oil media in engineering machinery, maintaining dimensional stability and mechanical properties even at high temperatures, suitable for harsh working conditions requiring continuous operation.

Low friction compatibility: Low surface friction coefficient, no adhesion to seals or metal contact surfaces, does not affect the motion accuracy of the sealing system, and reduces wear.

Installation and maintenance points:

Installation specifications: Clean the sealing groove, retaining ring, and O-ring surface, ensuring no burrs, oil stains, or impurities. Groove tolerance 0~+0.02 mm, surface roughness Ra≤0.8 μm.

During installation, avoid twisting or scratching the retaining ring. Install the O-ring first, then the retaining ring, ensuring the retaining ring fits tightly against the sealing gap side without offset.

The dynamic sealing surface clearance between the retaining ring and moving parts must be controlled to ≤0.05 mm to prevent abnormal wear.

Maintenance recommendations: Inspect the sealing system every 1000 working hours. If retaining ring deformation, surface scratches, or wear exceeding 0.2 mm are found, replace the retaining ring and O-ring simultaneously.

When the hydraulic oil contamination level exceeds the standard (NAS level > 8), shorten the inspection cycle to avoid impurities causing abnormal wear of the retaining ring and seals.