QA

How Strong Are Grade 8 Bolts

A grade 8 bolt is the highest grade SAE bolt. Grade 8 bolts have a minimum tensile strength of 150,000 PSI.

How many pounds can a Grade 8 bolt hold?

The tensile strength of a grade 8 bolt is 150,000 pounds per square inch. Tensile strength is the maximum load in tension (stretching) that a part can carry without breaking.

Is a 10.9 bolt stronger than Grade 8?

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 a 12.9 bolt stronger than Grade 8?

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.

Can you break Grade 8 bolts?

Can I drill out a broken grade 8 bolt with an electric drill? No problem. Use an HSS drill bit and take it easy. Use a speed somewhat lower than you would use for mild steel.

Is Grade 8 the strongest 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.

How much torque does it take to break a Grade 8 bolt?

My book shows a standard dry torque of 119 ftlbs for 1/2 grade 8.

Are Grade 8 bolts hard?

A grade 8 bolt is the highest grade SAE bolt. Grade 8 bolts have a minimum tensile strength of 150,000 PSI.

Can I use Grade 8 bolts for head bolts?

One more comment in answer to the original question: do NOT just go down to the hardware store and pick up some grade 8 bolts thinking they will work for head bolts. Head bolts are machined with a shoulder on the shank to fit tightly with the bolt hole, whereas hardware store bolts don’t have this as a rule.

How strong is a grade 8.8 bolt?

Bolt Grade Markings and Strength Chart Grade and Material Mechanical Properties Min. Tensile Strength (psi) Class 8.8 Medium carbon steel, quenched and tempered 800 830 Class 10.9 Alloy steel, quenched and tempered 1040.

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 the hardest grade bolt?

Grade 8 is the hardest, Grade 5 is medium, and Grade 2 is the softest. This is the most common grade of steel fastener and is the least expensive. Grade 2 bolts have no head marking, although sometimes a manufacturer’s mark is present. This grade of bolt is made from low or medium carbon steel.

What are Grade 8 bolts used for?

Grade 8 fasteners are considered hi-strength / high-tensile fasteners and are used in many highly industrial applications such as machinery, valves, pumps, vessels, motors, tractors, and even tanks… Although it may seem like a bolt is a bolt, there are significant differences in how each bolt is manufactured.

What is the shear strength of a Grade 8 bolt?

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

How much weight can a 1/2 inch bolt hold?

Proof Load Nom Bolt Size (in) Grade 2 5 7/16 5850 9050 1/2 7800 12100 9/16 10000 15500.

How much weight can a bolt hold?

For example, an eye bolt with a 1/4 inch shank can typically hold up to 600 pounds at a straight pull (no angle). However, at a 15 degree angle, the maximum weight capacity drops to 480 pounds (80% of the “straight pull” weight capacity).

Will 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.

Is Grade A stronger than Grade 8?

Its medium-carbon alloy steel has been quenched and tempered, ultimately making it possible to achieve an impressive tensile strength of 150,000 psi, compared to a grade 2 bolt’s 64,000 psi. In other words, a grade 8 bolt is more than twice as strong as a grade 2 SAE American Grade bolt.

What is stronger 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.

How much weight can a 3/8 grade 8 bolt hold?

A 3/8-inch bolt of this type is rated to 7,000 pounds in 6,000 psi concrete (basically granite) and 4,000 pounds in 2,000 psi concrete (hard sandstone).

How much force does it take to snap a bolt?

Using a standard wrench on a bolt or nut, the amount at force applied one foot away from the center of the bolt can be stated as foot-pounds force. To apply 100 ft-lbs torque to a bolt with a wrench long enough to allow a grip 2 ft. from the center of the bolt, would require 50 lbs. of force.

What steel is used for Grade 8 bolts?

The bolts are typically made of a medium carbon alloy steel that is plated in zinc for extra resilience. The grade 8 bolt can be identified via the flat, hexagonal head marked by six radial lines and occupy the highest position on the bolt-rating chart.

How many lines does a Grade 8 bolt have?

SAE Grade 8 Bolts: Head Marking: 6 radial lines.

How do you tell a Grade 8 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. A grade 8 bolt will have 6 radial lines on its head.