KF40RF2-D15 KF63RF2-D15 KRACHT Gear Pump 25 bar 3000 rpm

Product Overview

The KF40RF2-D15 and KF63RF2-D15 gear pumps, along with the KP0, KP1, KP2, KP3, and KP5 series, originate from Germany’s KRACHT gear pump technology platform. KRACHT is a family-owned enterprise founded in 1911, headquartered in Werdohl, Germany, and a world-renowned specialist in fluid control.

The KF Series features helical transfer pumps with a modular standard design. The KF40RF2-D15 has a displacement of 40 cm³/rev, and the KF63RF2-D15 has a displacement of 63 cm³/rev, with a standard operating pressure of 25 bar and peak pressure of 40 bar. Housings are manufactured from EN-GJL-250 (GG 25) grey cast iron or EN-GJS-400-15 (GGG 40) ductile cast iron. The D15 suffix indicates an integral relief valve for overload protection.

The KP Series features high-pressure gear pumps with hydraulic axial clearance compensation, with maximum operating pressures up to 300 bar. The KP Series comprises five sub-series – KP0, KP1, KP2, KP3, and KP5 – with displacements covering 1.4 to 300 cm³/rev. The KP1 is available in an aluminum version, while the KP2/KP3/KP5 are cast iron versions.

Key Interchangeability Advantage: Our KF/KP series gear pumps are manufactured to strict German KRACHT original design specifications, ensuring 100% direct interchangeability with original units. All mounting interfaces, flange dimensions, shaft configurations, and port positions are identical to the original product – no modifications required. Every pump undergoes 100% factory performance testing under simulated operating conditions (covering rated pressure, peak pressure, and full speed range performance curves), guaranteeing plug-and-play reliability with zero performance deviation.

Model Code Breakdown (based on KRACHT KF/KP Series designation rules):

• KF = Series: Helical Transfer Pump / KP = Series: High Pressure Gear Pump

• 40 / 63 = Nominal displacement (cm³/rev)

• RF = Mounting type: Flange mounting, parallel keyed solid shaft

• 2 = Shaft type / gear precision code

• D15 = Integral relief valve

• KP0 / KP1 / KP2 / KP3 / KP5 = High-pressure gear pump series and size codes

Technical Specifications 

KF40RF2-D15

• Product Series: KRACHT KF Series Helical Transfer Pump

• Brand: KRACHT (Germany)

• Pump Type: Helical external gear pump with integral relief valve

• Displacement: 40 cm³/rev

• Rated Operating Pressure: 25 bar

• Maximum Short-Term Pressure: 40 bar (peak)

• Operating Pressure (Relief Valve Setting): 15 bar

• Operating Speed: 1200 – 4000 r/min

• Media Viscosity Range: 12 – 20,000 mm²/s

• Media Temperature Range: -40°C to +150°C

• Housing Material: Grey cast iron EN-GJL-250 (GG 25)

• Gear Material: High-strength surface-hardened steel

• Gear Type: Helical gear with special gear geometry

• Bearings: Special composite plain bearings

• Seals: FKM (fluororubber)

• Mounting: Flange mounting

• Weight: Approx. 11.3 kg

KF63RF2-D15

• Product Series: KRACHT KF Series Helical Transfer Pump

• Brand: KRACHT (Germany)

• Pump Type: Helical external gear pump with integral relief valve

• Displacement: 63 cm³/rev

• Rated Operating Pressure: 25 bar

• Maximum Short-Term Pressure: 30 – 40 bar (peak)

• Inlet Pressure Range: 0.5 – 2 bar

• Maximum Speed: 3000 rpm

• Minimum Speed: 100 – 200 rpm

• Rated Flow (@1500 rpm): 94.5 L/min

• Volumetric Efficiency: ≥ 95%

• Flow Pulsation: ≤ 1%

• Media Viscosity Range: 2 – 1000 cSt (recommended 10 – 300 cSt)

• Media Temperature Range: -20°C to +120°C

• Ambient Temperature Range: -20°C to +60°C

• Housing Material: Grey cast iron GG 25

• Gear Material: 15CrNi6 case-hardened steel (surface hardness HRC 58–62)

• Gear Precision: Tooth profile accuracy IT5, backlash ≤ 0.03 mm

• Bearings: SKF single-row tapered roller bearings (rated life ≥ 10,000 hours)

• Shaft Type: Parallel keyed solid shaft

• Seal Type: NBR

• Mounting: Flange mounting

• Port Sizes: Inlet G2″, Outlet G1½”

• Weight: Approx. 17 kg

KP Series – General Specifications

• Product Series: KRACHT KP Series High-Pressure External Gear Pump

• Pump Type: External gear pump with hydraulic axial clearance compensation

• Operating Principle: Positive displacement

• Maximum Operating Pressure: 300 bar

• Direction of Rotation: Clockwise or counter-clockwise

• Mounting: Flange type

• Port Connections: Flange type

• Mounting Position: Optional

• Ambient Temperature Range: -20°C to +60°C

KP0 Series

• Displacement Options: 1.4 – 8.0 cm³/rev (KP0/1 – KP0/8)

• Maximum Operating Pressure: 280 bar

• Maximum Speed: 4000 rpm

KP1 Series

• Displacement Range: 1.5 – 22 cm³/rev

• Housing Material: High-strength extruded aluminum (KP1 aluminum) / Grey cast iron (KP1 cast iron)

• Gear Material: Case-hardened steel, ground tooth flanks

• Gear Teeth: z = 13, special tooth shape

• Operating Temperature: Seal-dependent (NBR ≤ 90°C / FKM ≤ 150°C)

KP2 Series

• Displacement Range: 20 – 62 cm³/rev

• Housing Material: Grey cast iron

• Gear Teeth: z = 14, special tooth shape

• Maximum Operating Pressure: 300 bar

• Operating Temperature: Seal-dependent (NBR ≤ 90°C / FKM ≤ 150°C)

KP3 Series

• Displacement Range: 58 – 125 cm³/rev

• Housing Material: Grey cast iron

• Gear Teeth: z = 14, special tooth shape

KP5 Series

• Displacement Range: 160 – 300 cm³/rev

Key Technical Advantages

1. Helical Gear Design for Ultra-Low Noise and Low Pulsation (KF Series)

All KF Series sizes feature helical gearing combined with a special gear geometry, effectively reducing displacement fluctuation and pressure pulsation. The KF63RF2-D15 achieves operating noise of ≤ 75 dB (measured at 1 meter), outperforming comparable products by an average of 5–8 dB. Flow pulsation is ≤ 1%, ensuring stable conveying.

2. Hydraulic Axial Clearance Compensation for High Efficiency Across All Pressures (KP Series)

The KP Series features hydraulic axial clearance compensation. Sliding plates located on the sides of the gears feature hydraulic pressure fields that automatically compensate for axial clearance at any operating pressure, with compensation independent of viscosity. This ensures high volumetric and mechanical efficiency at every operating point.

3. High-Strength Materials for Long Service Life and High Reliability

KF Series housings are manufactured from EN-GJL-250 (GG 25) grey cast iron, with gears made from 15CrNi6 case-hardened steel (surface hardness HRC 58–62) and SKF single-row tapered roller bearings (rated life ≥ 10,000 hours). KP2/KP3 Series housings and flange covers are both made of grey cast iron with high dynamic load capabilities, making them insensitive to pressure peaks and permanent oscillations.

4. Modular Design for Flexible Configuration

The KF Series features a modular standard design with optional integral relief valve, ATEX explosion-proof version, and noise-optimized version. The KP Series supports multiple pump combinations of the same or different sizes, with optional directly flange-mounted pressure relief valves or special valve assemblies. Depending on operating temperature and media, NBR or FKM sealing gaskets can be used to meet diverse application requirements.

5. Wide Media and Temperature Adaptability

The KF Series offers a media temperature range of -40°C to +150°C with broad viscosity adaptability (12 – 20,000 mm²/s). The KP Series is suitable for hydraulic oil, engine oil, HEES bio-oils, and flame-retardant liquids.

Application Areas

KF Series (Transfer Pumps)

• Equipment Forced Lubrication: Lubricating oil supply for marine gearboxes, wind turbines, and compressors

• Diesel Engines: Pre-lubrication and main lubrication

• Filtration Systems: Oil transfer and circulation

• Fuel Delivery: Fuel supply systems

• Petrochemical Industry: Crude oil gathering pipeline boosting

• Food Processing: Food-grade liquid transfer

• Automotive Manufacturing: Hydraulic power unit supply for stamping lines, gearbox assembly line oiling

KP Series (High-Pressure Pumps)

• Mobile and Stationary Hydraulic Systems

• Construction and Agricultural Machinery

• Municipal and Special Vehicles

• Industrial Hydraulic Systems

• Polyurethane and Chemical Industry

Expert Maintenance Tips

1. Model Confirmation and Selection

• The KF40RF2-D15 and KF63RF2-D15 are low-pressure transfer pumps (25 bar), while the KP Series are high-pressure gear pumps (up to 300 bar) – verify system operating pressure requirements during selection.

• The D15 suffix indicates an integral relief valve – this valve is for overload protection only and must not be operated in continuous relief mode.

• KP Series displacement ranges: KP0 (1.4–8 cm³/rev), KP1 (1.5–22), KP2 (20–62), KP3 (58–125), KP5 (160–300).

2. Pre-Installation Checks

• KF/KP Series pumps have a fixed rotation direction (clockwise or counter-clockwise) – verify matches system drive direction before installation.

• Confirm mounting flange type (flange type) and drive shaft specification (parallel keyed solid shaft) precisely match system interface.

• Never use hammer-driven installation – always use proper tools.

• Inlet pressure must be maintained within 0.5 – 2 bar.

3. First Start-Up & Media Priming

• Prime the pump housing with clean media before first start-up; ensure suction line is fully filled – never run dry.

• KF Series media temperature: -40°C to +150°C; KP Series ambient temperature: -20°C to +60°C.

• KF Series speed range: 1200 – 4000 r/min.

4. Filtration Requirements

• KF63RF2-D15 volumetric efficiency: ≥ 95%. Ensure media contains no large solid particles to prevent gear and bearing wear.

• Regularly monitor fluid cleanliness to prevent contaminants from accelerating gear and plain bearing wear.

5. Operating Monitoring

• KF Series continuous operating pressure must not exceed 25 bar; peak pressure must not exceed 40 bar.

• KP Series maximum operating pressure must not exceed 300 bar.

• For models with integral relief valves (D15), do not operate continuously in relief mode.

• Regularly check torque on pump and piping connection bolts to prevent loosening from vibration.