Are Grade 8 bolts or Grade 5 shear easier?
There exists an often quoted myth, that Grade 5 bolts are better in shear than Grade 8 since they will bend before breaking. Not true. Shear strength of alloy steel is approximately 60% of its ultimate tensile strength.
How much stronger is a Grade 8 bolt than a Grade 5?
A grade 8 bolt is the highest grade SAE bolt. Grade 8 bolts have a minimum tensile strength of 150,000 PSI. As a comparison, the ASTM A325 bolt is roughly equivalent to the SAE grade 5. A grade 8 bolt would be one that meets ASTM A490 standards.
Can you use a Grade 5 Nut with a grade 8 bolt?
Grade 8 bolts are stronger than Grade 5 bolts. No problem using them in the dif cover or crossmember. Yes they are stronger (higher tensile strength), but are more brittle (as you noted), and more prone to fracture.
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.
Are Grade 5 bolts OK for suspension?
Grade 5 works better in shear situations. Grade 8 works better in pull situations. The 5 will bend in shear before it breaks, 8 in shear will snap.
What does Grade 8 mean for a bolt?
Grade 8 – Grade 8 bolts are made from medium carbon alloy steel. The bolts of this grade feature 6 radial lines. The nominal size of the grade 8 bolts can be from 1/4″ to 1 1/2″. The minimum yield strength of this grade bolt is 130,000 psi.
What are Grade 5 bolts used for?
These bolts are generally used for non-critical joints and applications. A grade 5 bolt is distinguished by 3 radial lines and promises tensile strengths between 105,000 and 120,000 psi. They are most commonly found in automotive applications. This sought-after grade 8 bolt can be distinguished by six raised dashes.
Should nuts and bolts be the same grade?
What’s the answer? No, you should not use a mild steel tensile nut with a high tensile bolt. Match the bolt and nut grade or opt for a nut of a higher grade than the bolt.
Is stainless or grade 5 stronger?
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.
Can you use Grade 8 bolts for control arms?
Stick your head under any vehicle made and count the markings on the heads of all the hardware. You will find the charicteristic six hash marks indicating grade 8 on nearly everything even specialty hardware like upper control arm attachement bolts.
What are Grade 8 bolts?
Grade 8 bolts have a strength rating of 800,000 pounds per square inch. Grade 8 bolts are made from manganese steel and coated in zinc or yellow chromate. This coating gives the bolt a yellow color and prevents it from rusting. In general, grade 8 bolts can be used when high strength is required.
What is the strength of a Grade 5 bolt?
They have a proof load of 55000 psi, minimum yield strength of 57000 psi, and a minimum tensile strength of 74000 psi. Grade 5 bolts offer more strength and corrosion resistance than the grade 2 bolts and tend to see more use even though they cost a bit more.
What grade of bolt is best for shearing forces?
Grade 5 bolts are great for shearing forces, but are lousy under pulling or compressing forces because they can stretch or compress. If you’re concerned about shearing forces, then I would use a grade 5.
What is a Grade 2 bolt?
Grade 2 bolts are cheap but not very strong, grade 8 bolts are the strongest and most expensive, and grade 5 bolts are the most common. Refer to the charts to find the ideal tightening torque. Bolts are graded using various systems, but in the United States, the main bolt grading system was designed by SAE, the Society of Automotive Engineers.