Moog D951-2007 RKP-II Radial Piston Pump

Moog D951-2007 Hydraulic Pump (HP-R18A1-RKP019SM28J1Z00)

The Moog D951-2007 (HP-R18A1-RKP019SM28J1Z00) is a high-performance second-generation (RKP-II) variable displacement radial piston pump, built to satisfy the rigorous demands of industrial, maritime and high-performance motion control applications. The unit has a 9-piston rotary assembly that significantly reduces the piston clearance volumes, providing the industry’s lowest pressure ripples and exceptionally quiet sound. Its ferrous metal contact surfaces are hardened and wear resistant, ensuring a long service life even under continuous high load cycles.

Key Features

1. Advanced 9-Piston Architecture: Eliminates high-frequency flow pulsations, providing ultra-smooth fluid delivery and significantly lower decibel generation compared to legacy 7-piston designs.
2. Sliding Stroke Ring Mechanism: Offers rapid, dynamic displacement adaptation with precise flow and pressure compensation capabilities.
3. Robust Ferrous Construction: Internal components utilize strictly hardened steel elements, ensuring maximal resistance against particle contamination and mechanical fatigue.
4. High Power-to-Weight Ratio: Delivers up to 280 bar continuous pressure capability packed into a compact footprint weighing only 23 kg.
5. Modular Versatility: Fully compatible with diverse industrial fluid mediums and various multi-pump tandem configurations (SAE mounting interfaces).

Moog D951-2007 Radial Piston Pump Specifications

Compatibility

Compatible Equipment & Systems: Moog RKP-II control blocks, industrial servo-hydraulic power units, injection molding machinery rigs, metal forming presses, high-accuracy test and simulation benches.

Interchangeable / Legacy Cross-References: Direct historical substitute for legacy Bosch / Moog part configurations bearing reference code 0 514 400 007 and associated D951 series base variants.

Applications

• Marine and offshore deck machinery servo systems
• Industrial metal forming and stamping presses
• Plastics injection molding and extrusion units
• High-response multi-axis test rigs and structural simulation shakers
• Steel mill heavy-duty auxiliary hydraulic power packs

Marine Engineer Expert’s Guide

• Filtration Strictness: Because radial piston designs feature tight tolerances across the 9-piston sliding block interface, maintain a fluid cleanliness level of at least ISO 4406 18/16/13 (or better). Install high-efficiency pressure and return-line filters to prevent catastrophic scoring of the stroke ring.
• Initial Commissioning / Dry-Start Prevention: Never dry-start the D951-2007. Ensure the pump case is completely filled with clean operating fluid through the uppermost case drain port before initial motor engagement. Air pockets trapped within the housing will wipe out journal lubrication within seconds.
• Case Drain Piping Layout: Route the case drain line directly back to the hydraulic reservoir independently of other return lines. Ensure the termination point sits well below the minimum fluid level to minimize aeration, and verify that continuous backpressure on the drain port does not exceed 0.5 bar, preventing shaft seal blowout.

Frequently Asked Questions

What is the primary operational advantage of the Moog D951-2007 over older 7-piston pumps?

The D951-2007 incorporates an upgraded 9-piston rotary configuration together with a modified sliding stroke ring. This cuts fluid pulsation down significantly, ensuring drastically reduced vibration signatures and lower acoustic noise emissions that satisfy strict environmental noise guidelines.

Can this pump handle synthetic or water-glycol fire-resistant fluids?

Yes, while standard models optimize for mineral-grade hydraulic oils (HLP), specific variants within the RKP platform are structurally equipped with alternative seal configurations and metallurgy to safely process HFC and specialized synthetic fire-resistant fluids. Always confirm your exact service fluid compatibility against the specification key.

What causes premature wear in Moog RKP radial piston units?

The leading root causes of premature failure are fluid contamination, running the pump below fluid viscosity thresholds, or operating with a starved suction line leading to internal cavitation. Maintaining proper oil temperature control and clean inlet conditions maximizes longevity.