Question: How are bolt strengths measured?

A bolt’s overall mechanical strength can be measured by the degree of strain at which it finally breaks, while its yield strength designates the level at which it bends or deforms. … Steel bolts are graded according to newtons per millimeter squared for bolt tensile strength as compared to yield strength.

How is the strength of a standard bolt determined?

The tensile load a fastener can withstand is determined by the formula P = St x As. To find the tensile strength of a particular bolt, you will need to refer to Mechanical Properties of Externally Threaded Fasteners chart in the Fastenal Technical Reference Guide.

What does 9.8 mean on a bolt?

A metric bolt designated as ISO class 6.8 roughly corresponds in strength to an SAE Grade 2 bolt. Bolts of ISO class 8.8 and the slightly stronger class 9.8 roughly correspond to an SAE Grade 5 bolt. An ISO Class 10.9 bolt roughly corresponds to an SAE Grade 8 bolt.

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.

IT IS INTERESTING:  How long does the bolt recall take?

Is Grade 8 the strongest bolt?

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.

Is Grade 8 or 12.9 stronger?

Special markings on screw heads and nuts identify the fastener’s grade. Replace a graded fastener with same or higher grade (don’t replace a Grade 8 fastener with a Grade 5 or 2).

Table 1.

Grade/Class Strength
Metric Class 12.9 The highest metric class for strength, it exceeds Grade 8.

How strong is a Grade A bolt?

Grades of Bolts – Bolt Grade Markings & Bolt Strength Chart

Bolt Grade Markings & Strength Chart – Metric Steel Bolts
Head Marking Grade/Specification Tensile Strength min (MPa)
Class 10.9 1040 (150,000 psi)
Class 12.9 1220 (176,000 psi)
Usually stamped A-2 or A-4 A2 & A4 Stainless 500 Min 700 Typical

What does 8.8 on a bolt mean?

A property class (PC) is the metric equivalent of a grade in inch series terminology. … 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.

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.

IT IS INTERESTING:  What is dowel bar?

What does JDF mean on a bolt?

This is a great 8 bolt. Again you see JDF on that bolt on the top. Those initials again are manufacturers marking to indicate that this is their bolt and then you see 1, 2, 3, 4, 5, 6 slashes indicating it’s a grade 8.

Is there a harder bolt than Grade 8?

Grade 9 bolts are ideal for heavy-duty applications and are also often used in heavy machinery such as bulldozers. Not only are these bolts considerably stronger than they’re grade 8 counterparts, but they are also considerably more resistant to corrosive elements as they are made with yellow zinc chromate.

What does 12.9 on a bolt head mean?

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.

What grade is an 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.

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.

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.

IT IS INTERESTING:  Quick Answer: What size pilot hole do I need for a 3/8 lag bolt?

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.