What is M8 on a bolt?
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. For example, an M8 bolt with a standard coarse thread pitch of 1.25mm would require a hole of 6.75mm diameter to be tapped.
What do the markings on bolts mean?
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.
What are the markings on the head of a bolt?
What do they mean? The lines on the head of a bolt indicate its grade. SAE J429 (Society of Automotive Engineers) bolts have radial lines, whereas ASTM (American Society for Testing and Materials) uses a combination of letters and numbers to indicate the grade.
What is a M8 bit?
1,856 Posts. #2 · Aug 17, 2020. M6, M8, M10 etc are the thread sizes of metric bolts/screws. Often they are marked up as M8x20, or M8x30 or M8x40 etc. This is means it’s a metric bolt 8mm thick with a 20/30/40 shank (length).
What diameter is M8?
8mm
| Tap size | Basic major dia (mm) | Basic major dia (inch) |
|---|---|---|
| M8 x 1.25 | 8mm | .3150 |
| M8 x 1 | 8mm | .3150 |
| M10 x 1.5 | 10mm | .3937 |
| M10 x 1.25 | 10mm | .3937 |
What do the numbers and letters on bolts mean?
This will vary from manufacturer to manufacturer, but is usually one, two or three characters. The markings can identify the standard to which the bolt was made. For instance, if a bolt head contains three radial lines, then it’s a Grade 5 bolt. If it contains five radial lines, then the bolt is Grade 8.
How do you read bolt numbers?
How to Read Screw Sizes
- Read the first letter of the size. This the largest diameter: the measurement of the screw on the thread.
- Read the second number.
- Read the third number, generally the one following the “x.”
How do you indicate the drawing of a thread?
To display threads in drawings according to the ANSI, ISO or JIS standard, use the thread_standard Detail option in conjunction with hlr_for_threads. To display the threads in accordance with the ANSI standard, set thread_standard Detail option to std_ansi, std_ansi_imp, or std_ansi_imp_assy.
What does the B8 X stand for on a screw?
B 8 X. Symbol for identification of grade, i.e., “B8”, applied to head. Manufacture’s identification mark, e.g., “X” (on head of bolts and screws and on one end of studs and studs-bolts).
Where do I find the ASTM B8M Class 2 mark?
Manufacturer’s identification mark, e.g., “X” ( on head of bolts and screws and on one end of studs and stud bolts). ASTM A 193 Grade B8M Class 2 (Strain Hardened Material) Regular Series and Heavy Series 67611 B 8 M X Symbol for identification of grade, i.e., “B8M”, applied to head. Line stamped under “B8M”.
What does the B8 stand for in ASTM 193?
Line stamped under “B8”. Manufacturer’s identification mark, e.g., “X” ( on head of bolts and screws and on one end of studs and stud bolts). ASTM A 193 Grade B8M Class 1 Regular Series and Heavy Series X 67610. B 8 M. Symbol for identification of grade, i.e., “B8M”, applied to head.
What are the mechanical properties of metric bolts?
Definition of standard metric bolts The standarized properties of metric bolts are specified in the international standard ISO 898-1:2009 ‘Mechanical properties of fasteners made of carbon steel and alloy steel – Part 1: Bolts, screws and studs with specified property classes – Coarse thread and fine pitch thread’.