a Values do not apply to structural bolting.
b For structural bolting d ≥ M12.
c Nominal values are specified only for the purpose of the designation system for property classes. See Clause 5.
d In cases where the lower yield strength, ReL, cannot be determined, it is permissible to measure the stress at 0,2 % non-proportional elongation Rp0,2.
e For the property classes 4.8, 5.8 and 6.8, the values for Rpf,min are under investigation. The values at the time of publication of this part of ISO 898 are given for calculation of the proof stress ratio only. They are not test values.
f Proof loads are specified in Tables 5 and 7.
g Hardness determined at the end of a fastener shall be 250 HV, 238 HB or 99,5 HRB maximum.
h Surface hardness shall not be more than 30 Vickers points above the measured base metal hardness of the fastener when determination of both surface hardness and base metal hardness are carried out with HV 0,3 (see 9.11).
i Values are determined at a test temperature of −20 °C (see 9.14).
k Value for KV is under investigation.
l Instead of ISO 6157-1, ISO 6157-3 may apply by agreement between the manufacturer and the purchaser.