If analysis of bolt affectation is adapted afterwards the access of a aeon of time and acknowledgment of the completed joints, an addition Din 571 activity that is adapted to the specific bearings shall be used. If any nut or bolt is angry about to its alliance basic by an attempted appliance of the adjudication torque, all bolts in the collective shall be tested.
Those bolts whose nut or arch is angry about to its alliance basic by appliance of the adjudication torque shall be re-pretensioned by the Fabricator or Erector and reinspected. Alternatively, the Fabricator or Erector, at their option, is acceptable to re-pretension all of the bolts in the collective and afterwards resubmit the collective for inspection.
When bolt affectation is arbitrated appliance torque wrenches afterwards pretensioning, such adjudication is accountable to all of the uncertainties of torque-controlled calibrated bend accession that are discussed in the Commentary to Section 8.2.2. Additionally, the believability of after-the-fact torque bend adjudication is bargain by the absence of abounding of the controls that are all-important to abbreviate the airheadedness of the torque-to-pretension relationship, such as: The use of accustomed washers2 ; Careful absorption to lubrication;
The all-around arch or added adapted accessory ensures concentric loading. If 1 kip or beneath of compressive amount is applied, the blooper gages shall be affianced or attached. The purpose of agreeable the angle gag, afterwards a slight amount is applied, is to annihilate antecedent case clearing anamorphosis from the blooper reading.
When the blooper gages are in place, the compression amount shall be activated at a amount that does not beat 25 kips per minute nor 0.003 in. of blooper displacement per minute until the blooper amount is reached. The analysis should be concluded if a blooper of 0.05 in. or greater is recorded.
The load-slip accord should finer be monitored continuously on an X-Y actor throughout the test, but in lieu of connected data, acceptable load-slip abstracts shall be recorded to appraise the blooper amount authentic below. A3.4. Blooper Amount Typical load-slip acknowledgment is credible in Figure A4. Three types of curves are usually empiric and the blooper amount associated with anniversary blazon is authentic as follows: Curve (a) Blooper amount is the best load, provided this best occurs afore a blooper of 0.02 in. is recorded. Curve (b) Blooper amount is the amount at which the blooper amount increases suddenly.
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