AISC has a whole specification for stainless structures.
304 stainless bolts are not particularly high strength and probably should not be pretensioned. There are a number of high-strength stainless alloys which can be pretensioned when used as bolts.
What is your bolt spec and how are your bolts loaded?
@JLNJ I using M12x40 A2/A4-70 bolt to fasten a SS sheet and SS channel, with washer broad A2/A4 HV200 and two nuts M12 A2/A4-70. The first mounting nut is torqued 8Nm and second (jam) nut is torqued 48Nm. I want to find out if the torques applied to both the nuts will pretension the bolt or the bolt will remain in snug-tight situation. Can you help me how to find this out?
And if it is pre-tensioned, how do I design the bolt for pre-tension load.