Product Overview
MS27641-20 Intermediate Duty Airframe Ball Bearing, 1.25" Bore, Double PTFE Seals, 52100 Chrome Steel
Condition
Single unit available. Unused NOS — appears uninstalled, shows light surface grime consistent with long-term storage. Sourced from a government research facility. Evaluation: Visual inspection only. Function testing not performed. No documentation (FAA Form 8130-3 or Certificate of Conformance) is included; buyers requiring airworthiness traceability should verify documentation independently before installation in certified aircraft.
Ships same business day from Idaho. Packed carefully.
Product Overview
FAG KP20A.2TS is an intermediate duty airframe control ball bearing built to MS27641-20 / AS27641-20 standards. It provides low-friction radial support at pivot and joint points in aircraft flight control linkages, where low-speed oscillating loads and high vibration are the operating norm. The .2TS suffix identifies the double-seal variant: fiberglass-filled PTFE (Teflon) seals on both faces, offering lower friction and better chemical resistance than standard nitrile seals. Manufactured from 52100 chrome steel.
Key Features
- Bore diameter: 1.2500 in.
- Outside diameter: 2.2500 in.
- Inner ring width: 0.5000 in.
- Outer ring width: 0.4380 in.
- Seal type: 2TS — double fiberglass-filled PTFE (Teflon) seals, both faces
- Material: 52100 chrome steel
- Military standard: MS27641-20
- SAE standard: AS27641-20
- Series: Intermediate Duty Airframe Control Ball Bearing
- Pre-lubricated — grease type not confirmed for this specific unit; verify if shelf-life compliance is required
Applications
- Aircraft primary flight control pivot points: ailerons, elevators, rudders
- Secondary control mechanisms: flaps, trim tabs
- Airframe linkage joints subject to oscillating loads and high vibration
- Aerospace MRO replacement for MS27641-20 cross-reference applications
Frequently Asked Questions
What shaft and housing dimensions does this bearing require?
Shaft diameter: 1.2500 in. Housing bore: 2.2500 in. These are confirmed dimensions per the MS27641-20 standard.
How does the KP20A.2TS differ from the standard KP20A?
The .2TS suffix identifies double PTFE (Teflon) seals on both faces. The standard KP20A uses an open or metal-shielded configuration. PTFE seals reduce friction and improve resistance to aviation fluids and lubricants.
Is this bearing suitable for high-speed or continuous-rotation applications?
No. Airframe control bearings are designed for low-speed oscillating loads, not continuous high-RPM rotation. Using this in a motor or similar application will cause premature failure.
Does this unit include an FAA Form 8130-3 or Certificate of Conformance?
No documentation is included. Buyers installing this part in a certified airworthy aircraft must obtain the required traceability documentation independently before use.
What grease is this bearing pre-filled with?
MS27641-20 bearings are typically pre-lubricated with MIL-G-81322 grease (e.g., AeroShell 22 or Mobil 28). Grease type is not confirmed for this specific unit — verify against your maintenance requirements if shelf-life compliance matters.
Cross-references: MS27641-20, AS27641-20. Compatible with FAG, RBC, Schatz, and other MS27641-20 interchangeable sources. Verify fit and documentation requirements before installation.
