Workgroup Contents

Lecture 11.3.3 : Particular Aspects in Bolted Connections

1. GENERAL CONSIDERATIONS

2. OVERSIZE AND SLOTTED HOLES

3. FIT OF CONTACT SURFACES

4. DETERMINATION OF THE SLIP FACTOR

5. FITTED AND INJECTION BOLTS

6. TC BOLTS - LOAD INDICATOR WASHERS

6.1 A "Tension Control" (TC) bolt has a torque control groove and a torque control spline at the end of the threaded part as shown in Figure 6. When the torque reaches a definite value determined by the groove, the end of the screw breaks and the tightening is stopped.

6.2 A Load Indicator washer is a specially hardened washer with protrusions on one face, illustrated in Figure 7. The protrusions bear against the underside of the bolt head leaving a gap. As the bolt is tightened the protrusions are flattened and the gap reduced. At a specified average gap, measured by feeler gauge, the induced shank tension will not be less than the minimum required by Standards. Figure 8 shows a standard assembly in place before and after tightening the bolt.

7. PLATES PROTECTED AGAINST CORROSION

8. PROTECTED BOLTS

9. HYDROGEN EMBRITTLEMENT - STRESS CORROSION

10. CONCLUDING SUMMARY