Adjustable Bushing

Fasten in Three Dimensions

Monogram’s Adjustable Bushing fasteners operate by radial expansion, not through clamp-up or compression, the methods used by conventional fasteners.

This radial compression is provided by a series of alternately tapered segments which are allowed free axial movement on a supporting core shaft. When an axial load is applied, the outer “female” segments expand into the inner diameter of the hole while the outer “male” segments contract against the core shaft. All clearance between the hole and the fastener is thereby removed, providing an extremely rigid joint. 


What Adjustable Diameter Fasteners Do Best

  • Remove or reduce fretting or wear due to vibration or movement
  • Provide high shear strengths
  • Remove play and reduce structural vibration
  • Provide near-perfect alignment
  • Allow completely blind fastening
  • Provide interference-fit capability while requiring only commercial hole tolerances
  • Permit quick-release fastening
  • Provide an extremely rigid joint
  • Install easily with no special tools or training

Adjustable Diameter Fasteners, with their benefits and ease of installation, excel in these typical applications –

RIGID_STRUCTURAL_JOINTS_0                                ROD_END_BEARING_PINS_0

Rigid Structural Joints                                       Rod End Bearing Pins

Adjustable diameter fasteners                                Adjustable diameter fasteners
provide extremely tight radial                                remove all clearance between
fitsyet allow clearances for easy                             the pin and the inner race as well
installation and removal with no                             as between the pin and the yoke,
special tools or special training.                              eliminating backlash and assuring
                                                                           proper bearing rotation thereby   
                                                                           eliminating the troublesome
                                                                           problem of the inner race rotating.



Adjustable Clearance Fits                                  Taper Pin Replacement 

Adjustable diameter fasteners                                 Test verify that adjustable diameter
provide an adjustable clearance                              fasteners make structural or linkage
fit in everyday drill tolerance holes.                         joints more rigid or truly elastic
By simply torquing the nut the                                (zero hysteresis) than do press fit
desired radial tightness can be                                pins or taper pins. Use of adjustable
obtained. The assembly can be                               fasteners greatly simplifies
repeatedly adjusted to  compensate                        fabrication since only normal drill
for wear or to vary the fit as desired.                      hole tolerances are required.                                                                                           Interchangeability is maintained
                                                                           and costly taper reaming on            
                                                                           assembly is eliminated.


Adjustable Diameter Fasteners are available from Monogram Aerospace in the following configurations:




Series AFB


Series AFBB

Series EGP

Series DPB

Additional information on this product will be available soon.

Please contact us with any questions or to request a complete catalog.