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

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
Part Number Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
MS27640-3A 0.190 0.625 0.245 0.203
MS27640-3 0.190 0.777 0.297 0.270
MS27640-4 0.250 0.901 0.484 0.335
MS27640-5 0.313 1.250 0.558 0.375
MS27640-6 0.375 1.438 0.620 0.469
MS27640-8 0.500 1.688 0.620 0.500
MS27640-10 0.625 1.938 0.620 0.500
Intermediate Duty Ball Bearing
Governing Spec AS7949
Part Number Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
KP3AL 0.190 0.500 0.237 0.196
MS27641-3 0.190 0.625 0.297 0.234
MS27641-4 0.250 0.750 0.281 0.219
MS27641-5 0.313 0.813 0.297 0.234
MS27641-6 0.375 0.875 0.313 0.250
MS27641-8 0.500 1.125 0.375 0.313
MS27641-10 0.625 1.375 0.406 0.344
MS27641-12 0.750 1.625 0.437 0.375
MS27641-16 1.000 2.000 0.500 0.438
MS27641-20 1.250 2.250 0.500 0.438
Torque Tubes
Governing Spec AS7949
Part Number Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
B538 0.625 1.063 0.281 0.250
B539 0.750 1.188 0.281 0.250
B540 0.875 1.313 0.281 0.250
B541 1.063 1.500 0.281 0.250
B542 1.313 1.750 0.281 0.250
B543 1.563 2.000 0.281 0.250
B544 1.813 2.250 0.281 0.250
B545 2.063 2.625 0.281 0.250
B546 2.313 2.875 0.281 0.250
Light Duty Torque Tube
Governing Spec AS7949
Part Number Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
MS27646-38 0.625 1.063 0.281 0.250
MS27646-39 0.750 1.188 0.281 0.250
MS27646-40 0.875 1.313 0.281 0.250
MS27646-41 1.063 1.500 0.281 0.250
MS27646-42 1.313 1.750 0.281 0.250
MS27646-43 1.563 2.000 0.281 0.250
MS27646-44 1.813 2.250 0.281 0.250
MS27646-45 2.063 2.625 0.281 0.250
MS27646-46 2.313 2.875 0.281 0.250
Extra Light Duty Precision Torque Tube
Governing Spec AS7949
Part Number Bore Inner Diameter Outer Diameter Inner Ring Width Outer Ring Width
+.0000/-.0005 +.000/-.005
MS21428-38 0.625 1.063 0.281 0.250
MS21428-39 0.750 1.188 0.281 0.250
MS21428-40 0.875 1.313 0.281 0.250
MS21428-41 1.063 1.500 0.281 0.250
MS21428-42 1.313 1.750 0.281 0.250
MS21428-43 1.563 2.000 0.281 0.250
MS21428-44 1.813 2.250 0.281 0.250
MS21428-45 2.063 2.625 0.281 0.250
MS21428-46 2.313 2.875 0.281 0.250
Light & Heavy Duty Self Aligning Ball Bearing
Governing Spec AS7949
Part Number 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 0.19 0.625 0.245 0.203 0.278 ±10
MS27645-4A 0.25 0.75 0.281 0.219 0.329 ±8
MS27645-5A 0.3125 0.8125 0.297 0.234 0.388 ±8
MS27645-6A 0.375 0.875 0.313 0.25 0.463 ±8
MS27645-3 0.19 0.7774 0.297 0.27 0.314 ±10
MS27645-4 0.25 0.9014 0.484 0.335 0.399 ±10
MS27645-5 0.3125 1.25 0.558 0.375 0.569 ±10
MS27645-6 0.375 1.4375 0.62 0.469 0.614 ±10
MS27645-8 0.5 1.6875 0.62 0.5 0.811 ±10
MS27645-10 0.625 1.9375 0.813 0.625 0.925 ±10
* Dimensions and Values provided are for reference only. A full specification can be obtained at the Society of Automotive Engineering website