Product Overview

Experience superior hydraulic performance with our high-quality 25VQ21 Hydraulic Vane Pump Cartridge Kit. Engineered for demanding applications, this replacement cartridge kit is designed to restore optimal efficiency and extend the lifespan of your hydraulic systems, especially in heavy-duty machinery like excavators. It offers a precise fit and reliable operation, making it an ideal choice for maintaining peak equipment performance.

Product Specifications

• Model Numbers: 25VQ21 (compatible with 25VQ series, including 25VQ17, 25VQ19)

• Pump Type: Hydraulic Vane Pump Cartridge Kit

• Maximum Speed: Up to 2700 RPM

• Maximum Operating Pressure: Up to 3000 PSI

• Flow Rate: Approximately 21 GPM (Gallons Per Minute)

• Geometric Displacement: Approximately 66 mL/r (4.03 in³/r)

• Components Included: Assembled rotor, vanes, cam ring, inlet/outlet plates, and seals

• Design Features: Hydraulic balancing structure, twelve-vane system for low noise, independent cartridge for easy servicing.

Key Advantages & Selling Points

• Optimized Performance: Engineered for high-pressure and high-speed operations, ensuring consistent and powerful hydraulic function.

• Extended Service Life: Features a robust design with a hydraulic balancing structure and a 12-vane system that minimizes wear and reduces flow pulsation, contributing to longer pump life.

• Reduced Downtime: The cartridge unit design allows for quick and easy replacement of wear components without disconnecting the pump from the circuit, significantly reducing maintenance time and costs.

• Quiet Operation: The twelve-vane system contributes to lower amplitude flow pulsation, resulting in quieter system performance.

• Reliable Replacement: Manufactured to meet or exceed OEM specifications, ensuring seamless compatibility and dependable operation in your equipment.

Applicable Equipment & Scenarios

This 25VQ21 Hydraulic Vane Pump Cartridge Kit is universally compatible with a wide range of heavy machinery, ensuring optimal hydraulic performance in various demanding environments.

Primary Application: Excavator CAT Pumps

Specifically designed for CAT Excavator Pumps, this cartridge kit is essential for maintaining the robust hydraulic systems of Caterpillar excavators. It ensures precise control, powerful digging, and efficient operation, critical for heavy construction and earthmoving tasks.

Case Study: Enhancing Excavator Efficiency

A construction company faced frequent breakdowns and reduced lifting capacity in their fleet of CAT excavators due to worn hydraulic pumps. By replacing the old pump cartridges with the 25VQ21 kits, they observed an immediate improvement in hydraulic responsiveness, increased lifting strength, and smoother machine operations. This not only reduced unscheduled downtime but also significantly boosted project completion rates and overall operational efficiency.

Broader Equipment Compatibility:

• Construction Machinery: Paving machines, rollers, concrete pump trucks, concrete mixers, cranes, bulldozers.

• Industrial Applications: Injection molding machines, presses, steel machinery, mining and metallurgy equipment, pharmaceutical machinery, shipbuilding machinery, forklifts.

• Specific CAT Models: Including but not limited to CAT 980G, 970F, R1600 series, 960F, 924F, 928F, 518C, 815F series, 966G series, 972G series, R1300 series, 973, 814B, 816B, 936, G936, 631C, 633D, 637, 639D, 824B, 926, 926A, 930R, G926, IT28, IT28B, D350E, D400E, D8L, D9N, 966D, 966F, 966F II, 970F, 824C, 825C, IT18B.

Related & Similar Products

Beyond the 25VQ21 series, our product line includes a variety of high-performance hydraulic pump solutions that cater to diverse industrial needs. These similar products offer reliable and efficient power transmission across different applications:

• Vickers VQ Series Cartridge Kits (e.g., 20V, 35V, 45V): These kits provide similar high-pressure and low-noise characteristics for different flow requirements, widely used in industrial power units, mobile equipment, and marine applications.

• Eaton Vickers Hydraulic Vane Pump Kits: Known for their robust design and long service life, applicable in various industrial and mobile hydraulic systems, including construction machinery and agricultural equipment.

• Parker Denison Hydraulic Vane Pumps: Offers excellent efficiency and durability, suitable for heavy-duty industrial applications such as metal forming, logging, and refuse compaction.

• Yuken Hydraulic Vane Pumps: Renowned for stable operation and energy efficiency, frequently found in injection molding machines, machine tools, and other industrial automation systems.

• Piston Pumps: Offer higher pressure capabilities and are used in applications requiring precise control and high power density, such as large excavators, mining equipment, and offshore drilling rigs.

• Gear Pumps: Economical and robust, suitable for lower pressure applications and systems where simplicity and cost-effectiveness are key, like agricultural tractors and smaller construction equipment.

Installation & Maintenance: Common Issues and Solutions

Proper installation and regular maintenance are crucial for maximizing the lifespan and performance of your hydraulic vane pump cartridge kit. Here are common issues and their effective solutions:

1. Fluid Contamination

Issue: The most prevalent cause of hydraulic pump failure. Contaminants like dirt, debris, water, or air bubbles lead to increased wear, cavitation, and overheating.

Solution: Regularly inspect hydraulic fluid for discoloration, foam, or metallic particles. Implement proper filtration (ISO code 18/15 or better) and perform timely fluid changes. Ensure the reservoir is clean and properly sealed.

2. Cavitation & Aeration (Unusual Noises)

Issue: Characterized by whining, grinding, rattling, or a "marbles in a can" sound. Caused by restricted inlet flow, low fluid levels, clogged suction strainers, or air leaks in the suction line.

Solution: Maintain adequate fluid levels. Clean or replace clogged suction strainers. Inspect and tighten all inlet line connections and seals. Bleed air from the system during startup. Use swept bends instead of 90-degree elbows in suction lines to improve flow.

3. Overheating

Issue: Excessive heat can degrade hydraulic fluid and damage pump components. Causes include low fluid levels, poor lubrication, restricted flow, internal leaks, and operating beyond design pressure.

Solution: Ensure correct fluid type and viscosity. Regularly check and top off fluid levels. Inspect and clean the cooling system (heat exchanger, airflow). Address internal leaks promptly and avoid overloading the pump.

4. Fluid Leaks (External & Internal)

Issue: Visible fluid puddles, damp spots, or reduced system pressure. Caused by worn seals, damaged hoses, loose fittings, cracked housings, or internal seal failures.

Solution: Conduct regular visual inspections for leaks. Tighten all connections and fittings. Replace worn or damaged seals and gaskets immediately. Inspect the shaft journal for scoring if shaft seal leaks occur.

5. Reduced Performance & Pressure Loss

Issue: Sluggish equipment response, difficulty lifting loads, erratic movements, or a gradual drop in pressure. Often indicates internal leakage, worn components (vanes, cam ring, rotor, pressure plates), or blockages.

Solution: Systematically diagnose for internal leaks using a pressure gauge. Inspect and replace worn internal components. Clear any blockages in hydraulic lines or filters. Ensure proper pump calibration.

6. Improper Installation

Issue: Can lead to vibrations, premature wear, and pump failure. Common errors include loose fasteners, coupling misalignment, or incorrect rotation direction.

Solution: Ensure all mounting fasteners are properly tightened. Precisely align the motor and pump shafts during installation. Verify the correct rotation direction (indicated by an arrow on the pump body). Clean the shaft and deburr connection surfaces before assembly.