A Retrospect to the Standard Screw Sizes
The use of fasteners has grown extensively worldwide, increasing the need of coming up with standard screw sizes. Standardization prevents the use of improper screws, and ensures screws are compatible with the materials being used and are appropriate for the project at hand. Screw dimensions include the driver type — such as flat, Phillips or hex — length, shank diameter and threads per inch.
The demand for fasteners has extensively grown globally, especially in the world of online marketing. This growing demand has simultaneously increased the requirement for standard sizing of these hardware supplies.
By classification, the hassle of each time landing up with screws with different patterns and lengths can be greatly avoided. This even ensures that these rivets become comme il faut with the materials, being used in the construction or any build-up project. The various dimensions of these fasteners demand ofr use of various type of screwdrives, such as hex, Phillips, flat determining the shank diameter, length and threads per inch.
Screw’s numbering system
when standardization was done, the screws were put into 2 distinct numbering systems; the metric and U.S numbering systems. The metric measuring system lists out the diameter of these rivets in millimeters first and then secondly in thread pitch. The examples for this category include 6 mm x 1.0, 4 mm x 0.7, 5 mm x 0.8 etc. The U.S stadnard measurement system inlcudes screw with diameter sizes as 0, 1, 2 ,3, 4, 5, 6, 7, 8, 9, 10, 12, 14 and 16 and even in fractional sizes ranging from 1/4″ to 2″ in 1/16″. This is followed by threads and dash per inch falling between 6 and 80.
Diameter of screws
The first number metioned in the size charts for diameter must match the inner diamter of the washers ad nuts applied to them. The diameter of the rivet is measured at the shaft, just below the screw head. The diamter size ranging from 0 to 16 is declared by the American Society of Mechanical Engineers, thereby enabling the hardware sizing system to be extensively adopted worldwide. This kind of measurement made in standard U.S fractions was recently added and countries outside of America are also seen following this standardization.
Length of screws
While the pan head screw’s length is measured from the flat end of its round head to its tip, the length of the flat head screws measure from the top of the head to the tip of the rivet.
The length is the third item typically listed in the size chart and is identified by an ‘x’ symbol. For instance, a #8-20 x 3/4″ screw features 20 threads per inch and a shaft measuring 3/4″ in length and a 5/8-24 x 1″ screw has a diameter of 5/8″, 24 threads per inch and has a 1″ shaft.
There are some fasteners, which are measured as per the threads per inch sizing, execpt for their length and diameter such as 5/16 x 1/2″ and #10 x 1″
Threading of screws
This kind of measurement is at number 2 in the chart of standard screw sizes. The hyphen refers to the number of threads of screw shaft per inch. For e.g. a 1/4-28 sized screw has diameter of 1/4″ along-with 28 threads per inch and a #6-32 screw has 32 threads per inch on its shaft.
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