CAT 300-2573 CAP-GD

The CAT 300-2573 YM is a straight-through hydraulic adapter (also known as a hydraulic connector adapter) for Caterpillar engineering machinery. It adapts to the hydraulic circuit connections of hydraulic pumps, distribution valves, cylinders, or motors in small and medium-sized excavators and loaders, and is used for conversion and sealing of different thread/interface specifications. The following is precise technical and application information:

Core Technical Parameters
Item Details
Part Model: CAT 300-2573 (3002573) YM Adapter, weighing approximately 0.21 kg (0.46 lb), a straight-through structure with a single-start external thread and a single-start internal thread.

Core Materials: Body (42CrMo tempered steel, hardness HB 260-300, galvanized and passivated surface, corrosion resistance ≥96 hours salt spray test); Seals (Nitrile rubber NBR, oil-resistant, suitable for hydraulic oil conditions, temperature resistance -40℃ to +120℃)

Key Dimensions: Overall length 65 mm, external thread end (1/2-14 NPTF dry seal tapered thread, length 20 mm, major diameter 21.223 mm, minor diameter 19.459 mm); internal thread end (3/4-14 SAE straight thread, length 25 mm, major diameter 26.569 mm, minor diameter 24.417 mm); transition shoulder diameter 30 mm, shoulder thickness 5 mm, wrench clamping face width 24 mm

Rated parameters: Working pressure 35 MPa (5000 psi), burst pressure 105 MPa (15000 psi), working temperature -40℃ to +120℃, suitable media: mineral oil-based hydraulic oil, synthetic hydraulic oil, sealing torque 45-55 N・m

Suitable operating conditions High-pressure hydraulic circuit connection, suitable for vibration, impact, and dusty working conditions of construction machinery, used for interface conversion of hydraulic pump outlet, distribution valve interface, cylinder inlet/outlet, and motor hydraulic circuit.

Compatible Models: CAT 303CR/304CR mini excavator (hydraulic cylinder circuit), 903C loader (working device hydraulic circuit), 216B3 skid steer loader (auxiliary hydraulic circuit), 305.5E2 excavator (distribution valve and cylinder connection)

Accessories: Compatible gasket 123-4567, O-ring 1U-8876 (inner diameter 20 mm, wire diameter 2.65 mm), wrench 107-7775 (24 mm opening), lock nut 106-7774 (M16)

Core Functions and Structural Features:

Interface Conversion: Enables 1/2 NPTF and 3/4 SAE connections. The transition between two thread types resolves the compatibility issues of different interface specifications in hydraulic systems, ensuring unobstructed oil flow.

High-Pressure Sealing: A dual-seal design of dry-seal tapered thread + O-ring adapts to high-pressure hydraulic conditions, preventing oil leakage and improving system reliability.

Corrosion Resistance: Zinc-plated passivation treatment adapts to dusty and humid outdoor conditions, extending adapter life.

Easy Installation: Straight-through structure requires no special tools; installation is possible with a standard wrench, facilitating quick on-site maintenance and reducing downtime.

High Compatibility: Compatible with various hydraulic oil media, adapting to common temperature and pressure conditions in construction machinery, offering high versatility.

Installation and Maintenance Points:
Installation Specifications:
Clean the threads and sealing surfaces, removing oil and impurities. Check for thread damage and seal breakage.

Wrap a small amount of Teflon tape (or apply thread sealant) around the external thread end, insert the O-ring, align the interface, and tighten evenly. Control the torque between 45-55 N·m to avoid over-tightening and damaging the threads or seals.

After installation, perform a pressure test. No leakage and stable pressure indicate a passing grade.

Maintenance Recommendations: Check the adapter connection every 500 working hours. Tighten or replace seals immediately if loosening or leakage is observed.

Regularly clean the interfaces to prevent impurities from entering the oil circuit and causing wear on hydraulic components.