In this study, the rotation moment at the interfaces of tightly fitted parts with different tolerances for the shaft and hole system (sabil sized hole - shaft with different dimensions) was investigated. The steel part with a diameter of 15mm was drilled 0.282 "(7.163 mm fixed hole diameter) and prepared for interference fit. In order for the tightly fitted parts to be turned with a torque wrench, they must have a hex head and for this, a cylindrical insert piece was obtained by turning M8 bolts. Cylindrical parts were machined in different diameters (Ø 7.17-7.18-7.19) with different tolerances. Afterwards, the parts (hole-shaft) were tightly inserted in the press. Press pressure was measured and thrust force was calculated during the interference fit. One side of the parts joined by tight fit is fixed and turned with a torque meter until the interface slips. After the process, the thrust force and torque were examined for each tolerance value. At the specimen with a diameter of 7.17 mm, the press pressure could not be determined, but it was provided a tight fit and when a torque of 4.8 Nm was applied, the interface slipped. It was determined that the part with a diameter of 7.18 mm could be passed tightly with a force of 3460 N and the sliding at the interface was 11.59 Nm. Finally, it was founded that the part machined with a tolerance of 7.19 mm was pressed with a force of 6530 N and when the torque of 25.29 Nm was reached, it was found that slipping occurred.
Anahtar Kelimeler: Press fit, torque, tolerance
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