CBHYG-G/F Dual External Gear Pump

CBHYG-G/F Dual External Gear Pump Full Product Introduction

 

1. Basic Product Overview

 

The CBHYG-G/F Dual External Gear Pump is a coaxially integrated two-section combined Hydraulic gear pump with different pressure grades for front and rear pump chambers, widely applied in multi-load open-loop hydraulic system of construction machinery, forklifts and agricultural equipment. Derived from mature CBHY high-pressure gear pump platform, this model adopts G/F graded configuration: the G-grade pump section delivers high pressure for heavy-duty working circuits, while the F-grade section provides medium pressure for auxiliary functional loops. Instead of installing two separate Hydraulic gear pump units, it integrates two sets of external meshing gear assemblies inside one pump housing sharing a single drive shaft, realizing one power input to supply two independent hydraulic branches. It optimizes pipeline arrangement and installation space of the whole machine, serving as standard OEM matching and aftermarket replacement pump for wheel loaders, bulk material handling vehicles and farm harvesters.

 

Model Code Explanation

 

- CBHY: Base series of high-precision external meshing hydraulic gear pump for mobile machinery

- G: High-pressure grade section, rated 25MPa

- F: Medium-high pressure grade section, rated 20MPa

- G/F: Dual pump combination with front high-pressure G section and rear medium-pressure F section

Customizable displacement pairing for two sections, optional flat key/spline shaft and clockwise/counterclockwise rotation direction.

 

2. Core Technical Parameters

 

Item Specification 

Product Type Graded-pressure Dual Combined External Meshing Hydraulic gear pump 

Rated Pressure G section: 25MPa; F section: 20MPa 

Peak Instant Pressure G section: 28MPa; F section: 25MPa 

Rotational Speed Range 600–2400rpm 

Displacement Two sections with independent customizable displacements 

Pump Body Material Nodular cast iron integral housing, carburized quenched alloy steel precision ground gears 

Core Structure Floating side plate axial clearance compensation, radial hydraulic balance structure, heavy-duty DU composite bearings 

Sealing Assembly HNBR oil-resistant seals as standard; FKM high-temperature resistant seals optional 

Applicable Medium ISO VG46, VG68 anti-wear hydraulic oil 

Operating Temperature -20℃ ~ +90℃ 

Mounting Form Standard oval flange mounting, engine PTO direct drive 

Volumetric Efficiency ≥92% for both sections 

Warranty Period 1 year 

 

3. Structure & Working Principle

 

Composed of shared main drive shaft, two groups of driving and driven gear pairs, independent segmented pump cavities, floating compensation side plates, bearings and separated oil inlet/outlet ports, this unit functions as graded power supply core for the complete hydraulic system:

 

1. External power drives the common main shaft to rotate synchronously, two gear sets run simultaneously to form negative pressure in respective suction cavities and draw hydraulic oil from the shared oil tank.

2. The G high-pressure section outputs high-pressure hydraulic oil to drive main working hydraulic cylinders or hydraulic motors for lifting, digging and loading operations in the primary loop of the hydraulic system. The F medium-pressure section supplies stable flow for hydraulic steering, pilot valve control or transmission lubrication auxiliary circuits.

3. Each pump section is equipped with floating side plate compensation mechanism identical to standalone Hydraulic gear pump, which automatically offsets axial wear clearance under working pressure to reduce internal leakage and maintain long-lasting high efficiency.

4. The two hydraulic circuits operate in parallel with isolated oil passages without cross contamination of hydraulic oil, enabling simultaneous execution of main operation and auxiliary actions. Return oil from both sections flows back to the oil tank to complete circulation.

5. Coaxial integrated structure eliminates redundant transmission brackets and couplings, cutting mechanical power loss compared to two discrete Hydraulic gear pump installations.

 

4. Core Product Advantages

 

1. G/F dual pressure graded design matches load differences of main and auxiliary circuits precisely, avoiding excessive pressure energy waste and improving overall energy utilization of the hydraulic system.

2. Integrated dual-pump structure simplifies complicated piping layout, greatly saving installation space in narrow engine compartments with no need to redesign the original hydraulic system mounting structure during replacement.

3. Adopts radial hydraulic balance and heavy-duty bearing configuration, resisting gear eccentric abrasion and tolerating minor impurities in hydraulic oil on construction and farm sites.

4. Floating side plate compensation ensures stable volumetric efficiency after long-hour continuous operation, effectively preventing system pressure drop caused by gear wear.

5. Standardized mounting dimensions support plug-and-play replacement for old dual pumps, compatible with mainstream domestic machinery assembly requirements.

6. Flexible displacement pairing options cater to customized modification of various equipment hydraulic system.

 

5. Typical Application Scenarios

 

1. Main & auxiliary dual-circuit oil supply Hydraulic gear pump for wheel loaders’ integrated hydraulic system: G section for boom/bucket actuators, F section for hydraulic steering;

2. 3–8 ton forklifts, mini engineering vehicles compound hydraulic power assembly;

3. Large agricultural harvesters, forestry machinery for harvesting mechanism and walking auxiliary loops;

4. Equipment renovation upgrading: replace scattered single pumps to streamline hydraulic layout.

 

6. Fault Replacement Instructions

 

Replace the entire CBHYG-G/F dual pump assembly if either circuit suffers pressure attenuation, insufficient flow, inter-section cross oil leakage, persistent metal grinding noise or oil seepage at shaft end and flange surface. Common faults include gear tooth surface wear, floating side plate scuffing, bearing burnout and seal aging deterioration.