What is the difference between grade 2 and grade 5 bolts?

Grade 2 is a standard hardware grade steel. This is the most common grade of steel fastener and is the least expensive. Except a possible manufacturer’s mark,Grade 2 bolts have no head marking. Grade 5 bolts are hardened to increase strength and are the most common bolts found in automotive applications.

Is Grade 5 bolt stronger than Grade 2?

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.

Are Grade 2 bolts strong?

A grade 2 bolt is distinguished through its complete lack of markings and will usually have a tensile strength of between 60,000 and 74,000 psi.

What are Grade 5 bolts used for?

Grade 5 is specified under the Society of Automotive Engineers and is meant to be used for those applications requiring medium strength. Equivalent to the metric class 8.8 bolts, it is important to line up the right hardware if required to move from U.S. customary units (USC) to the metric system.

What grade bolts are the best?

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 steel bolts stronger than Grade 5?

The second most common stainless steel grade, this material is stronger than grade 2, slightly weaker than grade 5,or generally as strong as medium to low carbon steel. It is on the low middle end of the grade scale.

Should I use 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.

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.”

How much weight can a grade 2 bolt hold?

Proof Load

Nom Bolt Size (in) Grade
2 8
3/8 4250 9300
7/16 5850 12800
1/2 7800 17000

How can you tell if a bolt is grade 2?

A grade 2 bolt is distinguished through its complete lack of markings and will usually have a tensile strength of between 60,000 and 74,000 psi. These bolts are generally used for non-critical joints and applications.

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.

How many marks is a Grade 5 bolt?

Bolt Grade Markings and Strength Chart

Head Marking Grade and Material Mechanical Properties
Proof Load (psi)
3 Radial Lines Grade 5 Medium carbon steel, quenched and tempered 74,000
6 Radial Lines Grade 8 Medium carbon alloy steel, quenched and tempered 120,000
Grade A325 Carbon or alloy steel with or without boron 85,000

Are Grade 5 bolts galvanized?

Grade 5 is the most common grade used in manufacturing assembly. Galvanized plating protects the bolt from corrosion, typically used in outdoor applications.

Are stainless steel bolts grade 5?

Stainless Steel Grades &amp, Strength

Stainless commonly comes in grades 18.8 (304) or T316. 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).

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.

Are stainless steel bolts stronger?

Stainless steel is considered a soft metal meaning it is not great for many high load applications that require intense strength. However, certain grades are hardened to create a stronger version. It may effect the corrosion resistance of the fastener however. A classic example of this is Grade 410 Stainless Steel.

What kind of bolts do not rust?

When it comes to rust-resistant fasteners, stainless steel screws are the absolute best option. Stainless steel screws contain certain properties that allow them to withstand harsh outdoor elements to greater effect. As a result of their rust-resistant design, stainless steel fasteners see use in many outdoor projects.

What grade bolt has the highest shear strength?

12.9 Bolt Shear Capacity

  • 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.

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.

Can you use a grade 8 nut on a Grade 5 bolt?

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).

What grade bolt should be used for suspension?

SAE Grade 8, Metric 10.9

Common uses for Grade 8 bolts – suspension, steering, brakes, motor/transmission mounts, high-stress items.

Will a Grade 5 bolt shear?

The Grade 5 bolt will therefore always fail first whether in tension or shear. The only “gotcha” with the Grade 8 bolt is that, being harder, it is more “notch sensitive.” This means it is more sensitive to build up of stress concentrations caused by notches, nicks, and gouges leading to fatigue and failure.

What is the Rockwell hardness of a Grade 5 bolt?

J429 Mechanical Properties

Grade Nominal Size, inches Core Hardness, Rockwell
5 1/4 thru 1 C25 to C34
Over 1 thru 1-1/2 C19 to C30
8 1/4 thru 1-1/2 C33 to C39
Grade 2 requirements for sizes 1/4″ thru 3/4″ apply only to bolts 6″ and shorter, and to studs of all lengths. For bolts longer than 6″, Grade 1 requirements shall apply.

Are Grade 5 bolts heat treated?

Grade 5 fasteners are made from medium carbon steel, and are heat treated in order to achieve their higher mechanical properties.

How do you tell the grade of a bolt?

Determining Bolt Grade and Head Markings – YouTube

Is tensile strength the same as yield strength?

Yield Strength is the stress a material can withstand without permanent deformation or a point at which it will no longer return to its original dimensions (by 0.2% in length). Whereas, Tensile Strength is the maximum stress that a material can withstand while being stretched or pulled before failing or breaking.

How much weight can a 3/8 grade 5 bolt hold?

How much weight can a 3/8 inch 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). This is roughly the breaking strength range of carabiners and much higher than any rope’s maximum possible impact force.

Is proof load the same as yield strength?

So to summarize, proof load is a load that can be held without permanent deformation. It is the lowest force of the three forces that we are discussing. Yield strength is the force exerted at which a fastener permanently deforms. Yield strength is a greater force than proof load.

How do you know 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.

Are Grade 5 bolts zinc plated?

Grade 5 Bolts are equivalent to Metric 8.8 bolts, so when finding the right bolt, be sure to match the grades on the bolts being used. Grade 5 bolts can often be identified by the 3 marks on the head. Each Grade 5 bolt from U-Bolt-It are available zinc plated.

Are stainless steel screws stronger than zinc?

Choosing Between Zinc Alloys and Stainless Steel

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.

What is the yellow coating on bolts?

The yellow zinc plating of the fastener refers to the colour of the chromate that is applied once the zinc has been deposited on the fixing or fastener. This chromate prevents the zinc from corroding as well as increasing overall protection.

Are titanium bolts stronger than steel?

Titanium bolts are close to steel in terms of strength, with the benefit of being 47 percent lighter.

What does 8.8 mean on the head of a bolt?

The second number indicates one-tenth of the percentage of the part’s nominal yield strength compared to the part’s nominal tensile strength. 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.

What do letters on bolts mean?

Bolt Head Markings: What do they mean? | Fasteners 101 – YouTube

Why do Grade 5 bolts have 3 marks?

The higher the grade, the stronger the 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.

Will galvanized bolts rust?

Galvanized steel is coated with a thin layer of zinc. The zinc coating protects the steel beneath it from rust. It’s used to make nuts, bolts, screws, and nails resistant to degradation when they are exposed to the weather. Galvanized steel stands up to water well — as long as it’s not salt water.

Do stainless steel bolts have a grade?

18-8 Stainless Steel:

303 and 304 Stainless are the most commonly listed grades, the standard grade for stainless fasteners.

Are galvanized bolts strong?

Strength and Rust Resistance

A galvanized screw seems very strong to begin with – every bit as strong as stainless steel, surely. The problem is that this strength might only be skin deep, so to speak. Under that thin layer of hard-wearing zinc is plain black steel that is very susceptible to rust and corrosion.

What does A2 mean on a bolt?

A2 stainless steel fixings are made from an alloy containing a mixture of two or more metals. The steel within the fixing must contain at least 10.5% chromium to be considered or called stainless, and this chromium makes the metal more corrosion resistant and less likely to stain than other steels.