ASTM A193 Grade B8MLN Specification

ASTM A193 Grade B8MLN Specification for high tensile bolts, screws, stud bolts, anchor bolts, threaded rods and other threaded fasteners, made from 316LN / UNS S31653 stainless steel.

ASTM A193 Grade B8MLN is a standard material specification for corrosion resistant 316LN fasteners such as bolts, screws, studs, threaded rods and other externally threaded parts, for use in high tensile, high temperature and special purpose applications such as pressure piping & pressure vessels bolting. Grade B8MLN is a carbide solution treated 316LN stainless steel material having classified under tensile class 1 & 1D with minimum tensile requirement of 75 ksi, yield 30 ksi and maximum hardness limit of 223 HBW or 96 HRB. This specification covers requirements for chemical composition, mechanical properties, hardness, heat-treatment and recommended nuts-washers for Grade B8MLN Fasteners.

Chemical Composition

Element Austenitic Stainless Steel
UNS S31653 / AISI 316LN / 1.4429
CompositionA, %
Carbon 0.03 max
Manganese 2.00
Phosphorus 0.045 max
Sulfur 0.030 max
Silicon 1.00 max
Chromium 16.00 - 18.00
Nickel 10.00 - 13.00
Molybdenum 2.00 - 3.00
Nitrogen 0.10 - 0.16

A: The intentional addition of Bi, Se, Te, and Pb is not permitted.

Mechanical Properties

Tensile Class Diameter, Inch Tensile Strength,
min, ksi
Yield Strength,
min, 0.2% offset,
ksi
Elongation
in 4D,
min, %
Reduction
of Area,
min, %
Hardness,
max
Class 1 & 1D All Sizes 75 30 30 50 192 HBW or 90 HRB

Heat Treatment: Carbide Solution Treated in finished condition.

Recommended Nuts & Washers

Nut Specification Washer Specification
ASTM A194 Grade 8MLN ASTM A240 UNS S31653

Fasteners

Commonly Produced B8MLN Fasteners
Hex Bolts Heavy Hex Bolts Stud Bolts Threaded Rods Anchor Bolts
Eye Bolts Socket Head Cap Screws Countersunk Screws U Bolts Square Head Bolts