ASTM A193 Grade B8CLN Specification

ASTM A193 Grade B8CLN Specification for high tensile bolts, screws, stud bolts, anchor bolts, threaded rods and other externally threaded fasteners, made from 347LN stainless steel.

ASTM A193 Grade B8CLN is a standard material specification for nitrogen enhanced corrosion resistant grade 347LN stainless steel fasteners, for use in high tensile, high temperature and special purpose applications such as pressure piping & pressure vessels bolting. Grade B8CLN is a carbide solution treated 347LN stainless steel further divided into class 1 and class 1D, having similar requirements. ASTM A193 specification covers requirements for chemical composition, mechanical properties, hardness, heat-treatment and recommended nuts-washers for Grade B8CLN Fasteners.

Tensile Class

Property Description
Class 1 Carbide Solution Treated
Class 1D Carbide Solution Treated

Chemical Composition

Element Austenitic Stainless Steel
AISI 347LN / UNS S34751
CompositionA, %
Carbon 0.005 - 0.020
Manganese 2.00
Phosphorus 0.045 max
Sulfur 0.030 max
Silicon 1.00 max
Chromium 17.00 - 19.00
Nickel 9.00 - 12.00
Columbium 15 x Carbon Content min
Nitrogen 0.06 - 0.10

AThe 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,
maxA
Class 1 All Sizes 75 30 30 50 223 HBW or 96 HRB
Class 1D All Sizes 75 30 30 50 223 HBW or 96 HRB

Heat Treatment: Carbide Solution Treated
A: For sizes 3⁄4 in. in diameter and smaller, a maximum hardness of 241 HBW (100 HRB) is permitted.

Recommended Nuts & Washers

Nut Specification Washer Specification
ASTM A194 Grade 8CLN ASTM A240 TP347

Fasteners

Commonly Produced B8CLN 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