Product Overview
The KP30.51-05S3-LGF/GF/30.34-LGF/GF-D is a tandem pump configuration within the CASAPPA KAPPA 30 Series two-piece high-strength cast iron-bodied fixed displacement external gear pump family. CASAPPA, as Italy‘s largest manufacturer of high-pressure gear pumps and gear flow dividers, has been a global leader in hydraulic technology since its establishment in 1952.
The KAPPA 30 Series features a two-piece high-strength cast iron housing design, with a rigid and compact structure that enables the integration of multiple functions within a limited space. The series offers displacements from 21.99 to 73.82 cm³/rev, with operating pressures up to 300 bar. This model combines a 51.83 cm³/rev main pump section (KP30•51) with a 34.56 cm³/rev secondary pump section (KP30•34) in tandem configuration.
This product enables direct form-fit-function interchangeability with original CASAPPA units—no modifications to piping or mounting interfaces required. Our replacement solution strictly adheres to CASAPPA technical standards and undergoes 100% simulated in-service testing to ensure performance, reliability, and service life identical to OEM products. It is the ideal choice for hydraulic system maintenance and upgrades in excavators, wheel loaders, and other construction machinery.
Technical Specifications
Applicable Model (Primary):
Model Code Breakdown (per CASAPPA official documentation):
Product Series: KP30 — CASAPPA KAPPA 30 Cast Iron Gear Pump
First Section Displacement: 51 — 51.83 cm³/rev
Second Section Displacement: 34 — 34.56 cm³/rev
Flange/Shaft Configuration: 05S3 — Specific configuration code
Port Configuration: LGF/GF — Side inlet/outlet ports
Suffix D: Rotation direction indicator
Reference Models:
KP30.51-04S3-LGF/GF/30.38-LGF/GF D
KP30.51-04S3-67/PLP20.20 D-EL
KP30.51/30.34 S
KP30.51D0-06S8-LMD/MC-N-CSC
KP30.51D0-83E3-LED/EB-N
Series Technical Specifications (per CASAPPA official catalog):
Product Series: CASAPPA KAPPA 30 Cast Iron Gear Pump
Pump Type: Fixed Displacement External Gear Pump
Body Material: Two-Piece High-Strength Cast Iron Housing
Mounting Standards: SAE and European Standard Flanges
Fluid Compatibility: Mineral Hydraulic Oil
Seals: NBR (Standard)
Body Design: NSL / NSC
This Model Detailed Specifications:
First Section — KP30•51:
Geometric Displacement: 51.83 cm³/rev
Rated Operating Pressure (p₂): 290 bar (4,205 psi)
Peak Pressure (p₃): 310 bar (4,495 psi)
Maximum Speed: 2,500 min⁻¹
Minimum Speed: 350 min⁻¹
Theoretical Flow (@2,500 rpm): Approx. 129.6 L/min
Second Section — KP30•34:
Geometric Displacement: 34.56 cm³/rev
Rated Operating Pressure (p₂): 300 bar (4,350 psi)
Peak Pressure (p₃): 320 bar (4,640 psi)
Maximum Speed: 3,000 min⁻¹
Minimum Speed: 350 min⁻¹
Theoretical Flow (@3,000 rpm): Approx. 103.7 L/min
Tandem Pump Assembly Specifications:
Total Displacement: 51.83 + 34.56 = 86.39 cm³/rev
Total Theoretical Flow (@2,500 rpm drive speed): Approx. 233 L/min
Operating Temperature Range: -20°C to +80°C (standard seals)
Rotation Direction: D — Right-hand (clockwise, viewed from shaft end)
Key Technical Advantages
1. Two-Piece High-Strength Cast Iron Housing for Superior Durability
The KAPPA 30 Series features a two-piece high-strength cast iron housing design, providing excellent impact resistance and dimensional stability. The cast iron construction delivers outstanding rigidity and vibration resistance, with the rigid assembly ensuring reliability and high volumetric efficiency even at high operating pressures. The series is suitable for high-temperature operating environments.
2. Tandem Pump Modular Design — One Shaft, Two Circuits, Simplified System Layout
This model features a tandem pump configuration (KP30.51 / KP30.34) delivering two independent oil sources driven by a single shaft. This design significantly reduces the number of drive interfaces required, simplifies hydraulic piping layout, and is the ideal choice for complex multi-circuit hydraulic systems.
3. High Pressure Capacity for Heavy-Duty Applications
KP30•51 delivers 290 bar rated pressure and 310 bar peak pressure; KP30•34 delivers 300 bar rated pressure and 320 bar peak pressure. With continuous working pressure exceeding 250 bar and even higher peak pressure, the series is capable of handling various heavy-load operating conditions.
4. Floating Side Plate Pressure Compensation — High Volumetric Efficiency
The “three-piece” construction (two side plates and pump body) features side plates made of special materials (such as sintered bronze) that float under pressure, automatically compensating for clearance between gears and side plates. This maintains high volumetric efficiency throughout the pump‘s entire service life while reducing internal leakage.
5. Low-Noise Operation with Excellent Contamination Resistance
Optimized gear designs, such as “Phasing” noise-reducing gear technology, effectively reduce flow pulsation and operational noise. The robust cast iron construction combined with wear-resistant seal components provides excellent contamination resistance, extending service life in harsh operating environments.
Application Areas
Excavators: Hydraulic working systems for medium excavators (multi-circuit supply for boom, arm, bucket, swing)
Wheel Loaders: Hydraulic working systems and steering systems
Tractors: One circuit for steering, the other for implement lifting
Construction Equipment: Road rollers, motor graders, and other heavy equipment hydraulic systems
Material Handling Equipment: Forklift hydraulic systems, aerial work platforms
Industrial Hydraulic Systems: Machine tools, presses, conveyor systems, injection molding machines
Special Vehicles: Municipal vehicles, aerial work platforms, cleaning vehicles
Expert Maintenance Tips
1. Installation Precautions
The KAPPA 30 Series is a uni-directional rotation pump—verify that the system‘s required rotation direction matches the pump’s identification marking before installation. The suffix D indicates right-hand (clockwise) rotation.
Ensure coaxial alignment between the pump and drive shaft; flexible couplings are recommended to avoid radial loads on the pump shaft.
The suction line diameter must not be smaller than the pump inlet port; minimum speed should not fall below 350 min⁻¹ to prevent cavitation.
For this tandem pump configuration, pay special attention to the port connection orientation of both pump sections during installation.
2. Fluid Management
Use anti-wear hydraulic oils conforming to ISO VG 32 / VG 46 standards.
System fluid cleanliness must meet CASAPPA-recommended standards.
Operating temperature should be maintained within -20°C to +80°C.
Prime the pump by filling the housing with hydraulic fluid through the suction port before initial start-up. Never run the pump dry.
3. Start-Up & Commissioning
Use jog start method for initial start-up; verify correct rotation direction before continuous operation.
Allow the pump to run under no-load (low pressure) conditions for 2-3 minutes to purge air and ensure proper lubrication.
Gradually increase to operating pressure while monitoring noise, temperature, and system pressure for normal operation.
4. Routine Maintenance
The KAPPA 30 gear pump itself is maintenance-free; however, regular maintenance of the entire hydraulic system is essential for trouble-free pump operation.
Inspect system fluid cleanliness and condition every 1,000-2,000 operating hours.
Regularly replace return line filters and suction strainers to prevent contaminant ingress into the pump body.
