Table of Contents
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″. Bolts of this grade are heavy duty bolts that are strong and highly durable, and thus are used in a variety of heavy duty applications.
How can you tell if a bolt is grade 8?
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.
What is stronger Grade 8 or Grade 5 bolt?
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.
Is a Grade 8 bolt strong?
A grade 8 bolt is the highest grade SAE bolt. Grade 8 bolts have a minimum tensile strength of 150,000 PSI.
Is Grade 8 or 12.9 stronger?
A head with no markings is Grade 2, one with 3 lines spaced 120 degrees is Grade 5, and 6 lines spaced at 60 degree intervals is Grade 8.Table 1. Grade/Class Strength Metric Class 10.9 Similar to Grade 8. Metric Class 12.9 The highest metric class for strength, it exceeds Grade 8.
What is a grade 8.8 bolt?
Grade 8.8 Bolts are manufactured using medium carbon steel that has been quenched and tempered. Used in railroad equipment, motors, engines and processing equipment, grade 8.8 bolts exhibit good tensile strength and perform well in most environments.
What does 8.8 mean on the head of a bolt?
In the case of a 8.8 grade bolt the first figure signifies that the Tensile Strength is at least 800MPa. The second figure signifies that the fastener will begin to yield at 80% of the Ultimate Tensile Strength, i.e. at least 640MPa.
What does a triangle on a bolt head mean?
CoryPad (Materials) 26 Mar 07 15:58. The triangle is the manufacturers identification.
What does 10.8 mean on a bolt?
This number is 10% of the minimum tensile strength of the bolt (10% of proof strength for nuts). Thus, multiplying this number by 10 will produce the minimum tensile strength of the fastener in MPa.
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.
Do Grade 8 bolts bend or break?
Stronger tensile strength and more brittle is pretty much standard as you make harder steel alloys. Yes, from the point a Grade 8 bolt starts to bend to the point it fails will be less than a Grade 5.
Can you weld a Grade 8 bolt?
If you weld a Grade 8 bolt, you could soften it to the strength that Grade 5 possesses. No matter how little heat you use, heating the bolt in uncontrolled conditions will weaken it.
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.
Is a Grade 8 bolt stronger than stainless steel?
A common question is whether stainless steel is stronger that a grade 5 or grade 8 bolt. 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 are Grade 8 bolts used for on a car?
SAE Grade 8, Metric 10.9 They feature 6 radial lines on the head and are made from medium carbon alloy steel which has been quenched and tempered. Metric bolts have the grade number formed on the head face. Common uses for Grade 8 bolts – suspension, steering, brakes, motor/transmission mounts, high-stress items.
What is the strongest bolt head type?
Metric Grade 12.9 Hex Cap Screws Used in high stress environments, grade 12.9 fasteners are the highest class of metric cap screws. Where Grade 8 fasteners have a 150,000 psi tensile strength, 12.9 fasteners have a 180,000 psi tensile strength, making them more durable than the grade 5.
What is a grade C nut?
C. This nut grade denotation is for nuts that are used in heavy construction. They are marked with three curved lines around the central hole. This grade meets ASTM A563 specifications and is commonly used with ASTM A325 and ASTM A354 bolts.
Are grade 8.8 bolts Galvanised?
General grade high strength bolts (ISO grade 8.8) to BS 4395 Part 1, (equivalent to ASTM A325) can be galvanized without difficulty.
Is 8.8 bolt stainless steel?
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.
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.
