Aerospace Bearings

Airframe Control Bearings

Airframe Control Bearings are the broadest category of products that NPB offers. This Ball Bearing product is really the go-to part for oscillation in the bearing world. Due to their versatility and variety they are used for inserts for larger assemblies & pulleys, slight mis-alignment, or any application requiring slow rotation or oscillating motion. They are utilized across many non-aircraft industries due to their precision, radial and axial positioning, and excellence in oscillatory motion.

The most common industry standard for the airframe control bearings is the Society of Automotive Engineers (SAE) AS7949. This was formerly Mil-B-7949.

Some examples of airframe control bearing basic part numbers are(:)
MS27640 ..... KP_ ..................... Heavy Duty Ball Bearing
MS27641 ..... KP_A .................. Intermediate Duty Ball Bearing
MS27645 ..... KSP_, KSP_A ... Light & Heavy Duty Self Aligning Ball Bearing
MS27646 ..... B5__DD ............. Light Duty Torque Tube
MS21428 ..... MB5_DD ............ Extra Light Duty Precision Torque Tube
MS27644 ..... DPP_ .................. Double Row Ball Bearing
MS27647 ..... DW_ ................... Medium Duty Extra Wide Double Row Ball Bearing

Most of this product is produced in SAE 52100 chrome steel with cadmium or zinc plating with MILPRF- 81322 grease. Alternatively, 440C stainless steel and Mil-Prf-23827 grease is also available for this product.

For more information on Airframe control Bearings and your specific needs please contact us.

Heavy Duty Ball Bearing
Governing Spec AS7949
MS Part No. Part No. Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
MS27640-3A KP3L .1900 .6250 .2450 .2030
MS27640-3 KP3 .1900 .7774 .2970 .2700
MS27640-4 KP4 .2500 .9014 .4840 .3350
MS27640-5 KP5 .3125 1.2500 .5580 .3750
MS27640-6 KP6 .3750 1.4375 .6200 .4690
MS27640-8 KP8 .5000 1.6875 .6200 .5000
MS27640-10 KP10 .6250 1.9375 .6200 .5000
Intermediate Duty Ball Bearing
Governing Spec AS7949
MS Part No. Part No. Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
KP3AL .1900 .5000 .2370 .1960
MS27641-3 KP3A .1900 .6250 .2970 .2340
MS27641-4 KP4A .2500 .7500 .2810 .2190
MS27641-5 KP5A .3125 .8125 .2970 .2340
MS27641-6 KP6A .3750 .8750 .3130 .2500
MS27641-8 KP8A .5000 1.1250 .3750 .3130
MS27641-10 KP10A .6250 1.3750 .4060 .3440
MS27641-12 KP12A .7500 1.6250 .4370 .3750
MS27641-16 KP16A 1.0000 2.0000 .5000 .4380
MS27641-20 KP20A 1.2500 2.2500 .5000 .4380
Torque Tubes
Governing Spec AS7949
MS Part No. Part No. Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
  B538 .6250 1.0625 .2810 .2500
  B539 .7500 1.1875 .2810 .2500
  B540 .8750 1.3125 .2810 .2500
  B541 1.0625 1.5000 .2810 .2500
  B542 1.3125 1.7500 .2810 .2500
  B543 1.5625 2.0000 .2810 .2500
  B544 1.8125* 2.2500* .2810 .2500
  B545 2.0625* 2.6250* .2810 .2500
  B546 2.3125* 2.8750* .2810 .2500

* Bore inner diameter tolerance +.0010/-.0010
* Outer diameter tolerance: +0.0/-0.0015

Light Duty Torque Tube
Governing Spec AS7949
MS Part No. Part No. Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
MS27646-38 B538DD .6250 1.0625 .2810 .2500
MS27646-39 B539DD .7500 1.1875 .2810 .2500
MS27646-40 B540DD .8750 1.3125 .2810 .2500
MS27646-41 B541DD 1.0625 1.5000 .2810 .2500
MS27646-42 B542DD 1.3125 1.7500 .2810 .2500
MS27646-43 B543DD 1.5625 2.0000 .2810 .2500
MS27646-44 B544DD 1.8125* 2.2500* .2810 .2500
MS27646-45 B545DD 2.0625* 2.6250* .2810 .2500
MS27646-46 B546DD 2.3125* 2.8750* .2810 .2500

* Bore inner diameter tolerance +.0010/-.0010
* Outer diameter tolerance: +0.0/-0.0015

Extra Light Duty Precision Torque Tube
Governing Spec AS7949
MS Part No. Part No. Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
MS21428-38 MB538 .6250 1.0625 .2810 .2500
MS21428-39 MB539 .7500 1.1875 .2810 .2500
MS21428-40 MB540 .8750 1.3125 .2810 .2500
MS21428-41 MB541 1.0625 1.5000 .2810 .2500
MS21428-42 MB542 1.3125 1.7500 .2810 .2500
MS21428-43 MB543 1.5625 2.0000 .2810 .2500
MS21428-44 MB544 1.8125 2.2500 .2810 .2500
MS21428-45 MB545 2.0625 2.6250 .2810 .2500
MS21428-46 MB546 2.3125 2.8750 .2810 .2500
Light & Heavy Duty Self Aligning Ball Bearing
Governing Spec AS7949
MS Part No. Part No. Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width Inner Ring Shoulder Diameter Mis-Alignment
Angle
+.0000/-.0005 +.000/-.005 Approx. Degrees in Either Direction
MS27645-3A KSP3L .1900 .6250 .2450 .2030 .2560 ±10
MS27645-4A KSP4A .2500 .7500 .2810 .2190 .3280 ±8
MS27645-5A KSP5A .3125 .8125 .2970 .2340 .3890 ±8
MS27645-6A KSP6A .3750 .8750 .3130 .2500 .4620 ±8
MS27645-3 KSP3 .1900 .7774 .2970 .2700 .2970 ±10
MS27645-4 KSP4 .2500 .9014 .4840 .3350 .3960 ±10
MS27645-5 KSP5 .3125 1.2500 .5580 .3750 .5670 ±10
MS27645-6 KSP6 .3750 1.4375 .6200 .4690 .6120 ±10
MS27645-8 KSP8 .5000 1.6875 .6200 .5000 .7960 ±10
MS27645-10 KSP10 .6250 1.9375 .8130 .6250 .9220 ±10
Medium Duty Extra Wide Double Row Ball Bearing
Governing Spec AS7949
MS Part No. Part No. Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
MS27647-4A DW4K2 .2500 .6250 .5620 .5000
MS27647-4 DW4K .2500 .7500 .8750 .7500
DW4 .2500 .7500 .8750 .7500
MS27647-5 DW5 .3125 .8750 .9380 .8130
MS27647-6 DW6 .3750 1.0625 1.1880 1.0630
MS27647-8 DW8 .5000 1.4375 1.5000 1.3750
* Dimensions and Values provided are for reference only. A full specification can be obtained at the Society of Automotive Engineering website