12.9 Bolts. A 12.9 bolt is one of the highest grade of bolts produced. Known for their high tensile strength, they are built with both hex and Torx heads and are available in zinc or chrome finishes. … 12.9 Shear Strength. The minimum tensile strength of a 12.9 bolt is 1220 MPa.

Is Grade 8 or 10.9 stronger?

Class 10.9 is stronger than class 8.8. It is commonly found in high strength automotive applications. Class 10.9 is similar to grade 8. A low carbon steel for general use.

Is Grade 8 or 8.8 Stronger?

In terms of strength, 8.8 is equivalent to Grade 5, 10.9 is equivalent to grade 8. There are also 12.9 metric bolts, which are a little stronger than 10.9, and are a higher alloy steel.

What is the shear strength of a Grade 8 bolt?

Shear strength of a grade 8 bolt in good condition is 91,000 psi.

Which is stronger 8.8 or Grade 5?

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.

What grade is a 8.8 bolt?

Grade 8.8 Bolts belong to the DIN 933 grade 8.8 standard. This is a structural grade for bolts. This is a medium carbon steel bolt specification. These bolts are heat treated by quenched and tempered methods.

Is there a Grade 9 bolt?

Grade 9 Bolts Grade 9 structural bolts, also known as grade 9 hex cap screws, are one the strongest structural bolts that can be used today. While the typical grade 8 bolt has a tensile strength of 150,000 PSI, a grade 9 bolt has a tensile strength of 180,000PSI.

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.

What is 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.

Is a Grade 8 bolt strong?

Commercial-grade 8 bolts are the strongest option available. They’re made from medium carbon alloy steel and have markings that include six raised dashes. The psi of the bolt is 150,000, meaning that it can withstand great deals of pressure because of the way it was quenched and tempered.

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What does 8.8 mean on the head of a bolt?

So, in English, a PC 8.8 bolt is a bolt with a nominal tensile strength of 800 MPa and a nominal yield strength that is 80% of the bolt’s nominal tensile strength, or 640 MPa.

How much weight can a 8.8 bolt hold?

In round terms it is in 10’s of kg per square millimeter of the bolt. For example, a grade 12.9 bolt will not snap until every square millimetre of the bolt cross section is carrying a load of at least 120 kg. Similarly a grade 8.8 bolt will not snap until it is carrying a load of 80kg per square millimetre.

What is the shear strength of a Grade 5 bolt?

For example, an SAE grade 5 hex cap screw has a specified minimum tensile strength of 120,000 psi. Therefore, for design purposes, its shear strength could be reasonably assumed to be 70,000 psi.”

What is the strongest metal for bolts?

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.

Are stainless steel screws stronger than zinc?

Though some Zinc alloys can be very strong, overall stainless steel is stronger. However, zinc is a heavy element, and when alloyed with other metals it provides better corrosion resistance, stability, dimensional strength and impact strength.

Will Grade 5 bolts rust?

Many other grades exist but are used far less often. Grade 2, 5, and 8 are usually plated with a slightly blue-ish or yellow zinc coating, or are galvanized, to resist corrosion.

What steel is used for Grade 8 bolts?

Grade 8 bolts are specified for high strength applications and are commonly used in heavy manufacturing, such as tractor and truck fabrication for instance. The bolts are typically made of a medium carbon alloy steel that is plated in zinc for extra resilience.

Can you weld a Grade 8 bolt?

avoid welding grade 8 bolts. The grade 8 alloy is heat treatable and welding will likely seriously affect the base materials.

Is there a grade 12 bolt?

Do Grade 12 bolts exist? No SAE Grade 12 exists. On the metric side, there are no grades, only property classes. The highest strength property class is 12.9 which requires a tensile strength of approximately 1200 MPa and a yield strength of about 1080 MPa.

What grade is a shear bolt?

Registered. Normally shear bolts are Grade 2 and there is no soft grade #5 as it is either a grade #5 or not.

How strong is a Class 10.9 bolt?

Used in automotive applications and for bolting large and forged parts, metric 10.9 bolts exhibit high tensile strength and good wear resistance. Our metric grade 10.9 bolts meet ASTM A324 grade BD and SAE J429, grade 8 standards. The yield strength of the bolts is 940 and the tensile strength is 1040 MPa.

How strong is an 8.8 Bolt?

Property ClassNominal Size Range (mm)Tensile Strength, min(MPa)8.8Under 16 (incl.)8008.817-728309.81.6-1690010.95-1001040

Is a Grade 10 bolt stronger than a Grade 8 bolt?

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.

What is the shear strength of a bolt?

The shear strength of a bolt is a measurement of the minimum amount of force needed to break the bolt into two pieces. The shear strength of a metal bolt is approximately 0.6 times its tensile strength. A bolt commonly shears where its head meets the threads.

How strong is a Grade A bolt?

Bolt Grade Markings & Strength Chart – Metric Steel BoltsHead MarkingGrade/SpecificationTensile Strength min (MPa)Class 10.91040 (150,000 psi)Class 12.91220 (176,000 psi)Usually stamped A-2 or A-4A2 & A4 Stainless500 Min 700 Typical

Are titanium bolts stronger than steel?

The strength and low weight of Titanium make it exceptionally unique, and some grades of Titanium can be anywhere from two to four times stronger than some grades of Stainless Steel.

Are galvanized bolts stronger than stainless steel?

The more complex the alloy, generally the greater the strength, the higher the price, and the greater the labor costs. In general, galvanized steel is more ductile, and easier to work than stainless steel. Stainless steel is stronger and more corrosion-resistant than galvanized steel.

Are stainless steel bolts stronger than high tensile?

Stainless steel fasteners available on the Australian market in the main are equal to or higher in tensile strength than the carbon and low alloy steel fasteners commercially used, and are higher strength than most other corrosion resistant fasteners.

How hard is it to break a Grade 8 bolt?

The tensile strength of a grade 8 bolt is 150,000 pounds per square inch. A properly designed bolted connection will be able to withstand far more than the expected maximum stress to which it will be subjected while it is in service. …

How strong is a grade 12.9 bolt?

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.

Can Grade 8 bolts rust?

Grade 8 Steel Bolts 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.