Johnwoo1991
Materials
Do bolts according to ISO 898-1 (En 20898-1) grade 8.8 or 10.9 and 12.9 have any drawbacks when used for pressure retaining parts of ball valves, compared to ASTM A193 B7 and B7M?
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Can 8.8 bolting be used for ball valves?
- Thread starter Johnwoo1991
- Start date
Doug Hunter
Automotive
You need to compare the yield, ultimate and fatigue strength numbers directly. Are you replacing factory-installed screws? Be careful about the possibility of hydrogen embrittlement with the grade 12.9 bolts/screws. Corrosion testing may be advisable. Consulting a bolt/screw supplier, such as Acument, who works with both materials is recommended.
TugboatEng
Marine/Ocean
I believe the most significant difference between ISO 898 and ASTM A193 are the temperature ratings.
At ambient temperatures you should be ok substituting 898 for A193 but that goes out the window above 95°F.
At ambient temperatures you should be ok substituting 898 for A193 but that goes out the window above 95°F.
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