The Grade B8 Alloy-Steel and Stainless Steel Bolting Materials for High Temperature or High Pressure Service and Other Special Purpose Applications

This Grade B8 is heavily utilized in Wind farms, Sewage treatment, ships and chemical construction applications. The ASTM standard covers alloy steel and stainless steel bolting materials for high temperature or high-pressure service. This specification includes fasteners intended for use in pressure vessels, valves, flanges, and fittings. Although, this material is often available in national coarse (UNC) thread pitches, if being used in traditional applications, threads are specified 8 threads per inch (tpi) for diameters above one inch.

B8

Hex bolts, screws, stud bolts, double ended studs, Stud for foundation, wind energy bolts, Fasteners for wind turbines

Property class	Chemical composition
	C.	Mn.	Si.	P.	S.	Cr.	Ni.	Mo.	V.	Ti.
B8	0.08 max.	2.00 max.	1.00 max.	0.045 max.	0.030 max.	18.00-20.00	8.00-10.50	---	---	---

Class, Diameter In	Heat TreatmentB	Tensile Strength, min, ksi	Yield Strength, min, 0.2 % offset, ksi	Elongation in 4 D, min %	Reduction of Area, min %	Hardness, max
B8	carbide solution treated	75	30	30	50	223 HBC or 96 HRB

Class, Diameter mm	Heat TreatmentB	Tensile Strength, min, ksi	Yield Strength, min, 0.2 % offset, ksi	Elongation in 4 D, min %	Reduction of Area, min %	Hardness, max
B8	carbide solution treated	515	205	30	50	223 HBC or 96 HRB