In addition, most metric bolts are identified by a number stamped on the bolt head, such as 4.6, 5.8 or 10.9. The number has nothing to do with the size, but does indicate the relative strength of the bolt. The higher the number, the stronger the bolt. … A metric fastener could be designated M12 x 2, for example.

What do the numbers mean on metric bolts?

In addition, most metric bolts are identified by a number stamped on the bolt head, such as 4.6, 5.8 or 10.9. The number has nothing to do with the size, but does indicate the relative strength of the bolt. The higher the number, the stronger the bolt. … A metric fastener could be designated M12 x 2, for example.

What does M8 20 mean?

Here’s what the description means… M = Metric thread designation. 8 = Nominal diameter, in millimeters. 1.0 = Pitch (distance from thread to thread), in millimeters. 20 = Length, in millimeters (see below)

Does M10 mean 10mm?

Those are metric screw dimensions. M10 means a 10 millimeter outer diameter for the bolt or whatever piece it is; M12 means 12 millimeters. The part after the ‘x’ is the pitch — how many mm a thread is wide.

Which is bigger M8 or 5 16?

Well, quick answer is no. They are not the same and they are not interchangeable, although they can work under certain circumstances. The most important part is understanding the meaning of M8 and 5/16 to refer to the size of a metric screw or bolt, so then we can see why they aren’t the same thing!

How do you identify metric threads?

Metric threads are measured by their pitch. That is the distance from the crest of one thread to the crest of the next measured in millimetres. The pitch of a metric thread can be checked by direct measurement with a metric rule. Imperial threads have their pitch measured indirectly as a given number of teeth per inch.

How do you read metric bolt grades?

Strength Grades for metric fasteners are designated by a symbol comprised of 2 numbers, separated by a decimal. For example, 4.6 and 8.8. The first number represents 1/100 of the nominal tensile strength in N/mm^2.

What is M12 thread?

The first half (M12), is the size measurement (metric) taken across the outside diameter of the thread (which in this case is 12mm). The second half is the thread pitch, which is the measurement of threads/inch (which in this case is 1.75).

Whats bigger 10mm or 3 8?

10mm = just over 3/8 inch. 11mm = almost 7/16 inch. … 20mm = 25/32 inch. 21mm = just over 13/16 inch.

What does 8.8 mean on a bolt?

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.

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What does M16 bolt mean?

Metric bolts are made fractionally under their stated size, for instance an M16 bolt will have a shank diameter of typically 15.97mm. This means that a 16mm bolt will fit through a 16mm hole but to allow for misalignment between parts it is common practice to drill bolt holes slightly larger.

What size bolt has a 17mm head?

Bolt sizeSizeToleranceM1017mm17.407/16″UNF11/16″17.8618mm18.403/8″BSW18.43

What is M10 bolt size?

NOMINAL SIZE (D)BODY DIAMETERACROSS THE FLATSm1010.0015.73m1212.0017.73m1414.0020.67m1616.0023.67

What is the metric conversion for 5 16?

SAEMetricInch6.5mm0.2567mm0.2769/32″0.2815/16″0.313

What is the same size as 8mm?

MMApproximate Size In InchesExact Size In Inches8mm5/16 Inch0.31496 Inches9mmJust short of 3/8 Inch0.35433 Inches10mmLittle over 3/8 Inch0.39370 Inches11mm7/16 Inch0.43307 Inches

What does M8 mean on a bolt?

The defined diameter of metric bolts is actually slightly larger than the actual diameter of the bolt shaft. So an M8 bolt would have a shaft diameter that’s slightly under 8mm which means that the bolt should fit through an 8mm hole.

How do you tell the grade of a metric bolt?

Metric Bolt Grades—Metric grades are set according to rules set by the ISO (International Standards Organization). The grades consist of two numbers separated by a dot. The property class is expressed in raised or depressed numerals on top or on the side of the bolt head.

How can you tell the difference between standard and metric threads?

Metric fasteners are measured by length and pitch, or the distance between threads. So the systems are opposite in a way: The higher the TPI in a standard bolt, the finer the threads because there’s more squeezed into a set space. The greater the pitch on metric fasteners, the more distance between threads.

Is G thread same as BSP?

Is G thread the same as BSPP? The two types of thread are the same parallel straight. BSPP is the British Standard Pipe Parallel thread and it is also denoted by the letter G (ISO standard). Therefore, BSPP is the same as G.

Is a 3/8 the same as a 10mm?

It’s the same size. 3/8 is in inch and and its 10mm.

What size is a 3/8 bolt in metric?

Bolt DiameterMetricStandard3/8″14mm9/16″7/16″16mm5/8″1/2″19mm3/4″9/16″21mm13/16″

Is there a 10mm socket?

In fact, the 10mm socket is one of the most commonly used metric size sockets of all. It’s no secret that the majority of parts under the hood and in the car require a 10mm. The applications may vary from car to car, but the 10mm is absolutely vital to complete a project.

What is M2 screw?

M2 screws are typically used in the manufacture of small items of electrical equipment, laptops, cameras and mobile phones. The “M” designation for metric screws indicates the outer diameter of the screw in millimetres, so for an M2 screw, the outer diameter is 2mm.

How can you tell if a bolt is metric?

The metric screw thread is identified by the capital letter M, followed by the nominal diameter. Metric threads are measured by the distance between two adjacent threads in millimeters (pitch). Threads on a standard (inch based) fastener are measured by counting the number of threads per inch.

What does M10x1 25 mean?

Understanding Inch & Metric Thread Callouts For example, an M10x1. 5 (coarse) thread has a 1.5mm pitch, while an M10x1. 25 (fine) thread has a 1.25mm pitch. … For example, the thread “M10” automatically means a coarse pitch, while any added pitch callout, such as M10x1. 25, specifies a non-coarse pitch.

How strong is 8.8 bolt?

Grade and MaterialMechanical PropertiesMin. Tensile Strength (psi)Class 8.8 Medium carbon steel, quenched and tempered800830Class 10.9 Alloy steel, quenched and tempered1040

What does 4.6 bolt mean?

In 4.6, The first number 4 indicates 1/100 of nominal tensile strength . Hence the tensile strength = 400 Mpa. The second number indicates 10 times the ratio between lower stress(proof stress) and nominal tensile strength(yield stress ratio) means, 10 times the yield stress = 10 x 240/400 = 2400/400 = 6.

What size is a 9.8 bolt?

Property ClassSize Range (mm)Minimum Tensile Strength (106 Pa)4.8M1.6 – M164205.8M5 – M245208.8M1.6 – M368309.8M1.6 – M16900

What does m20 bolt mean?

M10-1.0 x 20 M = This designates the fastener is a metric size. 10 = The nominal diameter in millimeters. 1.0 = The thread pitch, or distance between threads, in millimeters. 20 = The fastener’s length, in millimeters.

How do I know what size bolt I need?

To measure the diameter of screws and bolts, you measure the distance from the outer thread on one side to the outer thread on the other side. This is called the major diameter and will usually be the proper size of the bolt.

What size head does an M12 bolt have?

SizeHead DiameterHexagon Socket SizeM8-1.2517.925.00M10-1.5022.406.00M12-1.7526.888.00M16-2.0033.6010.00