Specifications & Standards

ASTM Standards

Standard	Description	Application
ASTM A193	Alloy Steel and Stainless Steel Bolting	High Temperature Service
ASTM A320	Alloy Steel Bolting Materials	Low Temperature Service
ASTM A453	High Temperature Bolting	Grade 660 Applications
ASTM A194	Carbon and Alloy Steel Nuts	High Pressure & Temperature
ASTM A540	Alloy Steel Bolting	Special Applications

ISO Standards

Standard	Description
ISO 898-1	Mechanical Properties of Fasteners - Bolts, Screws and Studs
ISO 3506-1	Stainless Steel Fasteners - Bolts, Screws and Studs
ISO 15156	Materials for Use in H2S-containing Environments

Thread Specifications

Thread Type	Standard	Common Sizes
UNC - Unified Coarse	ASME B1.1	1/4" to 4"
UNF - Unified Fine	ASME B1.1	1/4" to 1-1/2"
Metric Coarse	ISO 724	M6 to M100
Metric Fine	ISO 724	M8 to M64
BSW - British Standard Whitworth	BS 84	1/4" to 6"

Material Grades