ASTM B7M Custom Bolts
ASTM A193 Grade B7M bolting is designned for sour gas service where there is high concertration of Hydrogen Sulfide gases present in prodcution situation. Per the specification at Sigma Fasteners we have our own heat treating furnace and hardness testing equipmet for onsite B7M modification and hardness testing. All B7M bolts require 100% hardness testing and at Sigma we keep it in house for complete control over the quality your products demand.