What are the grades of screw strength?

There are several grades of bolts but the three common grades for SAE are 2, 5 and 8. The common class (grades) for metric are 5.8, 8.8, 10.9 and 12.9. Each grade has a specific bolt strength. No matter the system used to grade the bolts, the higher number means the stronger the bolt.

What grade of screw is the strongest?

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 a grade 5 bolt?

Grade 5. Manufactured from medium carbon steel and hardened for greater strength and durability, a grade 5 bolt is distinguished by 3 radial lines and promises tensile strengths between 105,000 and 120,000 psi. They are most commonly found in automotive applications or those that require medium strength.

What is meant by 8.8 grade bolt?

Grade 8.8 Bolts are manufactured using medium carbon steel that has been quenched and tempered. Used in railroad equipment, motors, engines and processing equipment, grade 8.8 bolts exhibit good tensile strength and perform well in most environments.

Are socket head cap screws stronger than Grade 8?

Socket head cap screws are not grade designated as are hex head cap screws. A standard inch series socket head cap screw is 20% stronger than a Grade 8 hex head cap screw and 50% stronger than a Grade 5 hex cap screw. The tensile strength is a minimum 180,000 psi for sizes 1?

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.

What are the grades of metric bolts and screws?

Metric bolt grades and strength calculator to show proof strength, tensile strength, Vickers / Brinell hardness, minimum breaking torque and stress area of metric bolts and screws made of carbon steel and alloy steel with designations 4.6, 4.8, 5.8, 8.8, 9.8, 10.9 and 12.9. Some notes from ISO 898 metric screw threads standards:

What grade of bolt strength do I Need?

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. This bolt is an ASTM specification bolt that’s readily available in many home improvement and automotive stores.

What is the tensile strength of a bolt?

Tensile strength is the amount of pull the bolt can withstand before breaking. The method used for tightening the bolt is also dependent upon the grade of the bolt. The grades are indicated on top of the bolts as raised numbers or dashes.

What grade of bolts does Home Depot sell?

It’s virtually identical in terms of chemical and physical strengths and properties as an SAE Grade 5 bolt. Class 8.8: Class 10.9: Class 12.9: No matter the types of bolts you need for your home or mechanical project, The Home Depot has the bolts, washers and nuts you need for a secure fit.