CAT 258-8917 80.00mm Internal Diameter Straight Sleeve Hose

CAT 258-8917 is a large-diameter straight sleeve hose assembly for Caterpillar heavy-duty hydraulic systems. It has an inner diameter of 80.00mm (3.15in) and is suitable for the main oil circuit/return oil circuit of mining excavators, wheel loaders, and other equipment. It is used for high-pressure hydraulic oil delivery and features high pressure resistance, wear resistance, and anti-aging properties. The following are the core information:

Core Parameters
Item Details
Basic Attributes
Model 258-8917, straight sleeve hose assembly without bends, suitable for the main oil circuit/return oil circuit of high-flow hydraulic systems, equipped with straight sleeve crimp connectors at both ends, no angular deviation, used for high-pressure fluid delivery, suitable for medium-to-high-speed fluid conditions (flow rate ≤10m/s)

Compatible Models
Caterpillar 336/349 series excavators, 980/982 series wheel loaders, and other heavy-duty equipment, suitable for high-flow hydraulic circuits such as hydraulic pump outlet, main control valve inlet, and return oil filter assembly.

Material and Process Inner rubber layer: Oil-resistant synthetic rubber (NBR), resistant to hydraulic oil and mineral oil; Reinforcing layer: Multi-layer high-strength steel wire braid (4 layers), pressure resistance up to 42MPa; Outer rubber layer: Abrasion-resistant neoprene rubber (CR), UV resistant, aging resistant, and protected against mechanical damage, operating temperature -40℃ to +120℃

Key Dimensions: Inner diameter 80.00mm (3.15in), outer diameter 102.00mm (4.02in), standard lengths are commonly 1000mm/1500mm/2000mm (customizable), connector thread: 3″ SAE J518 Code 61 flange, compatible flange mounting hole diameter 102mm, weight approx. 5.2kg/m

Functional Parameters: Rated operating pressure 42MPa (6000psi), burst pressure 168MPa (24000psi), applicable media are mineral oil-based hydraulic oil and phosphate ester hydraulic oil, fluid temperature range -40℃ to + 120℃, volume expansion rate ≤2% (20℃, 42MPa)

Matching Components: Compatible with 3″ SAE J518 Code 61 flange fittings, matching sealing ring 156-7234. Installation requires dedicated crimping equipment (Cat Gold level crimping machine, crimping capacity up to 4″).

Installation and Maintenance Points:

Preparation before installation: Clean the fitting and hose ends to remove oil and impurities; check the hose for bulges, scratches, and aging; use a Cat Gold level crimping machine and dedicated molds, strictly following Caterpillar crimping specifications for crimping parameters; after crimping, a pressure test is required (42MPa pressure holding for 5 minutes with no leakage).

Installation Steps: Align the hose fittings at both ends with the equipment flanges, ensuring no twisting (torsion angle ≤5°); tighten the flanges with bolts, torque conforming to SAE J518 standard (approximately 800N・m for a 3″ flange); after installation, flush the system to remove pipeline impurities and prevent valve blockage.

Maintenance and Replacement: Check the appearance of the hose and the sealing of the joints every 1000 hours. Replace the hose immediately if cracks, bulges, or leaks appear in the outer rubber layer or at the joints. Avoid contact between the hose and sharp objects to prevent damage to the outer rubber layer and extend its service life.