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[MW:4475] Test Specimen Heat Treatment

By Materials & Welding
3.4.3 Test Specimen Heat Treatment
3.4.3.1 Two sets of tension specimens and one set of Charpy impact
specimens shall be tested. One set each of the tension specimens shall
be exposed to heat treatment condition A. The second set of tension
specimens and the set of Charpy specimens shall be exposed to heat
treatment Condition B.
a) Condition A – ....... Time at temperature shall be no less than 80%
of the actual holding time of the vessel portion exposed to the
maximum vessel-portion temperature.
b) Condition B – ....... Time at temperature shall be no more than
120% of the actual hold time of the vessel portion exposed to the
minimum vessel-portion temperature

Can anybody explain this 80% & 120% with simple example?

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