Oil and gas
Oil and gas
The failure mode
Wet hydrogen sulphide cracks hard steel. A B7 stud at 32 HRC can fail in service without any warning and without any loss of section — the crack simply runs through it.
What we supply
Hardness-controlled B7M or L7M below 22 HRC, with 2HM or 7M nuts, every piece hardness tested and the reading printed on the certificate.
Grades used here
B7M-48 … 427 °C
ASTM A193 Grade B7M
Chromium-molybdenum alloy steel (AISI 4140 / 4142 / 4145)
690MPa min
L7M-101 … 427 °C
ASTM A320 Grade L7M
Chromium-molybdenum alloy steel (AISI 4140 / 4142 / 4145)
690MPa min
2HM-48 … 427 °C
ASTM A194 Grade 2HM
Medium carbon steel
—MPa min
Gr 7M-101 … 427 °C
ASTM A194 Grade 7M
Chromium-molybdenum alloy steel (AISI 4140)
—MPa min
Recommended coatings
Need a quotation?
Send us the grade, size and quantity. We reply within one working day with price, lead time and the certificate package included.