High Strength Bolts For Structural Bolting Bolts are fasteners with external threads designed for driving through holes in assembled parts. These fasteners are tightened or released through torqueing a nut. High strength bolts are made from high-strength carbon steel or from tempered alloy steel.

What are high strength bolts?

High Strength Bolts For Structural Bolting Bolts are fasteners with external threads designed for driving through holes in assembled parts. These fasteners are tightened or released through torqueing a nut. High strength bolts are made from high-strength carbon steel or from tempered alloy steel.

What is the strongest grade of bolt?

The strongest commercial-quality bolt is grade 8, marked by six raised dashes; its medium-carbon alloy steel has been quenched and tempered to achieve a tensile strength of 150,000 psi.

What is the difference between a common bolt and a high strength bolt?

Ordinary bolts are generally made of ordinary steel (Q235) and only need to be tightened. Ordinary bolts are generally 4.4, 4.8, 5.6 and 8.8 class. High-strength bolts are generally 8.8 and 10.9 class, of which 10.9 class are mostly. The screw holes of ordinary bolts are not necessarily larger than high-strength bolts.

How are high strength bolts identified?

The higher the grade, the stronger the bolt. English bolts have radial lines on their head to identify the grade, or strength class. The number of lines on the bolt head is 2 less than the actual grade. So, for example, a grade 5 bolt will only have 3 radial lines on its head.

Is Grade 8 or Grade 5 stronger?

Grade 8 bolts have been hardened more than grade 5 bolts. Thus they are stronger and are used in demanding applications such as automotive suspensions. Grade 8 bolts have 6 evenly spaced radial lines on the head. Grade G is roughly equivalent to Grade 8.

Should I use Grade 5 or Grade 8 bolts?

Grade 8 bolts have been hardened more than grade 5 bolts. Thus they are stronger and are used in demanding applications such as automotive suspensions.

Are Grade 8 bolts stronger than Grade 5?

Are Grade 8 bolts the strongest?

These grades start at grade 2 and go up to grade 8, which is the strongest SAE American Grade bolt available. A grade 2 bolt is distinguished through its complete lack of markings and will usually have a tensile strength of between 60,000 and 74,000 psi.

Whats stronger Grade 8 or Grade 5 bolt?

What grade bolt should I use?

Bolt Grade Markings Each grade has a specific bolt strength. No matter the system used to grade the bolts, the higher number means the stronger the bolt. For most home and automotive applications, you won’t need anything more than a grade 8 bolt strength or metric class 10.9.