Quick Answer: What Is The Difference Between 8.8 And 12.9 Grade Bolts?

What is the meaning of 8.8 grade in a bolt?

8.8- This type of grade is often referred to as the structural grade for bolts.

When a bolt has a grading of S, it means that it can withstand a stress of 45 to 49.9 metric tonnes per 6.45 cm².

This grading, which is typically stamped on the head of the bolt, has the same tensile strength as a grade 8.8 bolt..

How can you tell if a bolt is Grade 5?

Grade 5 bolts are case hardened, meaning the bolt has been heated enough to hardened the outside of the bolt but not enough to harden the inside portion. Grade 5 bolts are identified by 3 evenly spaced radial lines on the head.

What is class 12.9 Steel?

Grade 12.9 Bolt is a high tensile bolt that has a diameter of 12.9 mm and the lengths vary from 20mm to 200mm based on the application requirement. … There are studs, hex bolts, U bolts, T bolts and many other types in this grade.

What Bolt is stronger than Grade 8?

Grade 8 / Grade G 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. Grade G nuts are used with Grade 8 bolts.

What is the difference between grades of bolts?

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 the number means the stronger the bolt.

What is the strongest bolt grade?

grade 8The 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.

Are stainless bolts stronger than Grade 8?

Stainless steel bolts are rated for corrosion resistance. Bolt strength is rated in PSI (pounds per square inch). A stainless steel bolt has the same PSI rating as a grade 5 bolt (125,000 PSI). A grade 8 bolt has a stronger rating with a PSI of 150,000.

How strong is a grade 8.8 bolt?

Mechanical propertiesGrade, material & conditionNominal thread diameter size range [mm]Tensile strength (min) [MPa]Class 5.8 Low or medium carbon steel; cold worked5–24520Class 8.8 Medium carbon steel; quench and temperedUnder 16 (inc.)80017–72830Class 8.8 low carbon Low carbon boron steel; quench and tempered9 more rows

What is the hardest bolt you can buy?

BUMAX® Ultra has proven itself as the world’s strongest bolt – in various highly-demanding critical fastener applications around the world where standard fasteners are simply inadequate.

How much force can a bolt take?

Steel bolts are graded according to newtons per millimeter squared for bolt tensile strength as compared to yield strength. For example, a steel bolt with a rating of 5.5 will provide roughly 500 newtons/mm2 of bolt tensile strength and approximately 400 newtons/mm2 of yield strength.

What is a 12.9 grade bolts?

The minimum ultimate tensile strength of the Grade 12.9 Metric Hex Head Bolts is about 1242 Mpa or 180,000 PSI, making them the highest grade of bolts produced.In fact, the Grade 12.9 Nuts is known for their high tensile strength.

How hard is a 12.9 bolt?

So 12.9 = 12x9x10 = 12×90 = 1080MPa. So, and applied tensile force of 1080 MPA will cause a permanent plastic deformation of 0.2% in the length of the screw (if it’s 1” long, it will be 1.002″ long after.) Note that this is only on hex head capscrews, and only on regular carbon steel.

Are higher grade bolts more brittle?

One common misconception about bolts is that a higher rated bolt is stronger, yet more brittle, and therefore lower grades should be used in places like in suspension systems so they can deform rather then break. This is wrong! There are two types of forces a bolt experiences, tension and shear.

What grade are ARP bolts?

Explains how ARP polished stainless steel and black oxide finished 8740 bolts are stronger than SAE Grade 5 or Grade 8 fasteners, as well as ISO 8.8 and 10.9 rated metric bolts. ARP accessory bolts are nominally rated at 170,000 psi tensile strength, far superior to the 120,000 of Grade 5 and 150,000 Grade 8 ratings.

What are 12.9 bolts made of?

The standard was withdrawn in 2012. The 12.9 is the Class head marking under ASTM F568M standard for Bolts of a high grade (1220 MPa), being Alloy steel, quenched and tempered. ASTM F568M is an ASTM International standard for metric bolts, screws and studs that are used in general engineering applications.

Is a 12.9 Bolt stronger than Grade 8?

Many fasteners (screws, etc.), especially smaller sizes, are typically not graded—their strength isn’t specified….Table 1.Grade/ClassStrengthMetric Class 8.8Similar to Grade 5.Metric Class 10.9Similar to Grade 8.Metric Class 12.9The highest metric class for strength, it exceeds Grade 8.11 more rows

Can Grade 8 bolts be reused?

Mechanically, bolts may be reused provided the bolt never exceeded its yield point: a simple enough definition, but one that is more complicated than it may appear. This is because it is nearly impossible to verify if a bolt has ever been tensioned past the yield point.

What grade bolt has the highest shear strength?

They are commonly used at high stress points in connecting devices.12.9 Bolts. A 12.9 bolt is one of the highest grade of bolts produced. … 12.9 Shear Strength. The minimum tensile strength of a 12.9 bolt is 1220 MPa.

Will Grade 8 bolts rust?

Grade 8 bolts have 6 evenly spaced radial lines on the head.” Unlike stainless steel, which is highly resistant to corrosion, steel, however reinforced, will oxidize over time and rust. Grade 8 bolts that are not galvanized or plated with yellow zinc, however, are cheaper.

What are Grade 5 bolts used for?

The A325 bolt strength, or SAE grade 5 bolt strength, is usually used for structural bolting projects. There are three primary materials used in the making of A325 bolts, and they are: Type 1 – medium carbon steel or alloy steel, or boron steel.

Is there a grade 10 bolt?

Class 10. This is a metric nut grading similar to the SAE grade 8 classification, which is used in conjunction with Class 10.9 bolts. This strength of nut is used in automotive, and structural industries, as well as in high temp applications.