G5 GM5 Series Hydraulic Gear Pump | G5-16 GM5-20 GM5-25 | High Pressure External Gear Pump

Chengyuan Hydraulic presents the G5 and GM5 Series external gear pumps, designed as high-reliability power components for industrial and mobile hydraulic systems. This range covers displacements from 6cc to 25cc, including core models such as GM5-20-AF13R, GM5-25-AF13S, and G5-16-1F13S.

As the “heart” of the hydraulic circuit, Chengyuan ensures that the G5/GM5 series provides 100% Drop-in Interchangeability regarding mounting flanges (SAE or standard), shaft extensions, and port sizes. Constructed with high-strength extruded aluminum housings and precision-ground gears, and validated through 100% Simulation Load Testing, each pump delivers exceptional volumetric efficiency and long-term durability under rated pressures—making them the ideal alternative to high-priced OEM components.

Technical Specifications 

• Series Models: G5 / GM5 (High-Pressure Version)

• Displacement Range: 6.0 $cm^3$/rev – 25.0 $cm^3$/rev

• Rated Pressure: 20 MPa (200 bar)

• Max Pressure: 25 MPa (250 bar)

• Rated Speed: 2000 – 3000 rpm

• Max Speed: 3500 rpm (subject to displacement size)

• Shaft Types: A15R (Straight Key), F13S (Spline), etc.

• Mounting Flange: AF (2-Bolt Rhombus) or Standard F Flange

• Drive Method: Direct drive (Flexible coupling recommended)

• Working Medium: Mineral-based hydraulic oil

Key Technical Advantages:

• High-Strength Aluminum Housing: The body is manufactured using a specialized extrusion process, providing superior tensile strength and toughness. This prevents housing distortion under continuous 20MPa pressure, maintaining precise internal clearances.

• Precision-Lapped Gear Sets: Gears are made from high-quality alloy steel, carbonized, quenched, and precision-ground to micron-level accuracy. This significantly reduces flow pulsation and mechanical noise during operation.

• Floating Side Plate Pressure Compensation: The internal floating bush/side plate structure uses system pressure to automatically compensate for end-face clearances. This design ensures over 90% volumetric efficiency across various speed ranges.

• High-Load DU Bearings: Equipped with high-performance DU composite bearings, the pump features excellent load-bearing and anti-impact properties, protecting rotating parts even under frequent start-stop or heavy-load cycles.

Application Areas:

• Material Handling: Forklift lifting systems and small stacker hydraulic controls.

• Agricultural Machinery: Tractor hitch systems and auxiliary circuits for harvesters.

• Construction Equipment: Pilot pumps and auxiliary power for mini-excavators and road rollers.

• Industrial Power Units: Compact hydraulic power packs and machine tool clamping circuits.

Expert Maintenance Tips:

• Initial Start-up: Before the first start-up after installation, the pump must be primed with hydraulic oil through the outlet port to prevent dry-running damage to the side plates.

• Suction Environment: Ensure the suction line is perfectly sealed to avoid aeration and cavitation. Suction resistance should not exceed -0.03MPa.

• Fluid Filtration: To protect the precision gears, the system must be equipped with filters of at least 20μm. Oil cleanliness should be maintained at NAS Class 10 or better.