IS 3757 HSFG Bolts: Specs, Grades 8.8S & 10.9S, Sizes
IS 3757 is the Indian standard for high strength structural bolts, used as HSFG (high strength friction grip) bolts in steel buildings, bridges, towers and industrial structures. The bolts come in two structural property classes, 8.8S and 10.9S, typically in sizes...
HR vs HV Bolts: EN 14399-3 vs EN 14399-4 Explained
HR bolts (EN 14399-3) and HV bolts (EN 14399-4) are the two hexagon-head preloaded bolt systems in the EN 14399 series. Both are designed for the same minimum preload, 0.7 × fub × As, and both are tightened using the methods...
ASTM B7 vs EN 14399: Which Bolt Standard to Use?
Quick Summary ASTM A193 Grade B7 and EN 14399 are not competing alternatives — they solve different bolting problems. B7 is a material specification for chromium-molybdenum alloy steel studs used in high-temperature, high-pressure flange connections on piping, valves, and pressure vessels...
Bolt Grades Explained: How to Choose the Right Strength Class
Bolt grades, also called strength classes, indicate a fastener’s tensile and yield strength. Metric grades (e.g., 8.8, 10.9) are marked as two numbers on the bolt head — the first indicates tensile strength in MPa, the second the yield-to-tensile ratio. SAE...
