751992-2 - Hamilton Sundstrand Corporation Annular Ball Bearing

751992-2 – Hamilton Sundstrand (Collins Aerospace) High-Precision Annular Ball Bearing

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Overview

The 751992-2 is a flight-critical, genuine Original Equipment Manufacturer (OEM) annular ball bearing, engineered and manufactured by Hamilton Sundstrand (now part of Collins Aerospace) for the most demanding aerospace applications. This is not a standard industrial bearing; it is a high-precision component designed to provide low-friction rotational support for shafts within complex, high-speed machinery such as Integrated Drive Generators (IDGs), Air Cycle Machines (ACMs), Constant Speed Drives (CSDs), engine starters, or fuel controls.

Manufactured to the exacting internal standards of Hamilton Sundstrand/Collins Aerospace, this bearing is constructed from specialized, ultra-clean bearing steels and is designed to operate reliably under extreme conditions of speed, temperature, and load. Its dimensional accuracy, internal clearances, and lubrication are precisely controlled to ensure optimal performance and longevity within the parent component. The reliability of critical aircraft systems depends on the integrity of bearings like the 751992-2.

Key Features

• Genuine Hamilton Sundstrand / Collins Aerospace OEM Part: Guarantees the part is fabricated to the exact material specifications, dimensional tolerances, precision grades (ABEC/ISO), and quality standards required by the original equipment designer.

• High-Precision Annular Ball Bearing: Designed for low-friction, high-speed rotational support, capable of handling both radial and thrust loads as specified by the application.

• Specialized Bearing Steel: Manufactured from premium, vacuum-remelted bearing steels (such as M50 tool steel for high-temperature applications or 440C CRES for corrosion resistance), ensuring maximum fatigue life and durability. (Specific material must be confirmed by OEM documentation).

• Engineered for Extreme Environments: Designed to withstand the high rotational speeds (tens of thousands of RPM), elevated temperatures, and significant g-loads encountered within aerospace accessory drives and environmental control systems.

• Low-Friction, High-Efficiency Operation: Precision-ground raceways and high-quality rolling elements minimize rotational torque, contributing to system efficiency.

• Flight-Critical Component: Essential for the safe and reliable operation of critical aircraft power generation, environmental control, and engine start systems.

Technical Specifications

• Part Number: 751992-2

• Component Type: Annular Ball Bearing (Deep Groove or Angular Contact - must be confirmed by OEM drawing).

• OEM Manufacturer: Hamilton Sundstrand (Collins Aerospace)

• Material: Must be confirmed by OEM documentation. Likely a high-performance bearing steel (e.g., M50, 440C CRES).

• Finish: Per OEM specification.

• Dimensions (ID, OD, Width): Per Hamilton Sundstrand / Collins Aerospace Engineering Drawing 751992. (These are specific, likely non-standard dimensions).

• Precision Class (ABEC/ISO): Per OEM specification (typically high precision, e.g., ABEC 5, 7, or 9).

• Lubrication: Per OEM specification (often specialized aerospace greases or oils).

• Seals/Shields: Per OEM specification (may be open, shielded, or sealed).

• Governing Specification: Hamilton Sundstrand / Collins Aerospace Engineering Drawing 751992.

Aircraft Compatibility

This is a component-level part used within specific Line Replaceable Units (LRUs) manufactured by Hamilton Sundstrand / Collins Aerospace. It is not directly installed on an airframe but within a component. These components are used on a vast range of aircraft.

• System Application (Typical): Integrated Drive Generators (IDGs), Air Cycle Machines (ACMs), Constant Speed Drives (CSDs), Starters, Fuel Controls.

• Representative Aircraft Platforms (Utilizing HS/Collins Components):

  • Boeing 7-Series Airliners

  • Airbus A3XX Series Airliners

  • Bombardier Global, Challenger, CRJ Series

  • Embraer E-Jets, Phenom Series

  • Gulfstream G-Series

  • Various Military Aircraft

Note: This bearing is specific to a Hamilton Sundstrand / Collins Aerospace component. Verification of applicability is the absolute responsibility of the installer. Always consult the current version of the applicable Component Maintenance Manual (CMM) or Illustrated Parts Catalog (IPC) for the higher-level assembly to confirm part number eligibility.

Applications

• Providing low-friction rotational support for high-speed shafts in IDGs, ACMs, starters, etc.

• Handling significant radial and axial loads generated by rotating machinery.

• Critical for maintaining precise shaft alignment and preventing vibration within the parent component.

Why Choose 751992-2?

Bearings used in high-speed aerospace applications operate at the limits of material science and manufacturing technology. The genuine OEM 751992-2 is the only part guaranteed to meet the specific requirements for material purity, heat treatment, internal geometry, precision tolerance (ABEC/ISO class), lubrication, and load/speed ratings defined by the component designer. Using a non-certified, industrial-grade bearing introduces an unacceptable risk of premature failure from fatigue, overheating, or seizure, which could lead to catastrophic failure of the entire IDG, ACM, or starter, potentially resulting in an in-flight emergency.

The extreme performance demands placed on a bearing like the 751992-2 often necessitate the use of advanced materials like M50 tool steel (AMS 6491). M50 is a through-hardening martensitic steel renowned for its exceptional hot hardness (resistance to softening at high temperatures) and high fatigue strength, making it ideal for bearings in turbine engine accessory drives and generators where operating temperatures can exceed 500°F (260°C). Achieving these properties requires a precisely controlled vacuum-induction melting/vacuum-arc remelting (VIM/VAR) process to minimize impurities, followed by a specific austenitizing, quenching, and multiple tempering heat treatment cycle. The manufacturing process also involves grinding the raceways to sub-micron tolerances and potentially applying specialized surface treatments or coatings (like silver plating on cages) to enhance lubrication and prevent galling at extreme speeds (DN values often exceeding 2 million). This level of material science and manufacturing precision is fundamental to the bearing's ability to survive and perform reliably in its intended application.

Note: This is a flight-critical component intended for installation within a higher-level assembly. It must only be installed by a certified repair station or technician specifically authorized and equipped to overhaul the parent component (e.g., IDG, ACM), in strict accordance with the Component Maintenance Manual (CMM). Installation requires specialized tools, controlled environments (clean room), and specific lubrication procedures. Improper handling or installation will lead to premature failure.

Documentation

All technical data, including material specifications, dimensions, tolerances, and installation procedures for the 751992-2 bearing, are proprietary to Hamilton Sundstrand / Collins Aerospace. This information is contained within the official Component Maintenance Manual (CMM) for the higher-level assembly. No public-facing documentation is available.