Metric Bolt Thread Pitch

Thread pitch is the number of threads per inch.

Metric bolt thread pitch.

The smallest or largest pitch diameter that fits onto a screw or into a nut including all of the form deviations such as lead thread angle taper and roundness. Metric thread pitch table metric pitch table metric diameter pitch mm coarse standard fine standard 3mm 0 50 0 35 4mm 0 70 0 50 5mm 0 80 0 50 6mm 1 00 0 75 8mm 1 25 1 00 10mm 1 50 1 25 12mm 1 75 1 25 14mm 2 00 1 50 16mm 2 00 1 50 18mm 2 50 1 50 20mm 2 50 1 50 22mm 2 50 1 50 24mm 3 00 2 00 27mm 3 00 2 00 30mm 3 50 2 00 33mm 3 50 2 00 36mm 4 00 3. For example a thread pitch of 1 5 means that the distance between one thread and the next is 1 5mm. The thread depth is 0 614 x pitch.

Here is lightning bolt s metric bolt thread pitch chart. This bolt is one half inch in diameter has 13 threads per inch and is one inch long. 8 nominal diameter in millimeters. 1 0 pitch distance from thread to thread in millimeters.

M12 x 25 12 mm diameter coarse thread is assumed 1 75 mm 25 mm long. The rest of the dimensions are tabulated values from the asme standard. Ultimate tensile and proof loads for metric bolts according iso 898 1 mechanical properties of fasteners made of carbon steel and alloy steel part 1. As i explained at the top of the page metric bolt sizes are stated as diameter x distance between threads x length.

Bellow are iso din accepted thread pitch charts for commonly found metric fasteners. Thread pitch metric fasteners are specified with a thread pitch instead of a thread count. An example of a sae bolt size is 1 2x13x1. Bolt depot common metric thread pitches standard fine super fine jis.

The metric system s pitch is commonly viewed as the reverse of tpi in that it is the distance measured between two adjacent threads. Functional diameter is a measure of the ability to assemble the thread. The thread angle is 60 o. Bolts screws and studs with specified property classes coarse thread and fine pitch thread.

Maximum rounded form minor diameter d 3max d 2max 0 5h 2r min 1 cos 60deg arccos 1 t d2 4r min. 20 length in millimeters see below this example illustrates how a coarse threaded screw may appear. The thread pitch is the distance between threads expressed in millimeters measured along the length of the fastener. In the imperial inch system threads are commonly referred to by measuring an inch and counting how many threads are inside that measurement.

Here r min is minimum root radius t d2 is pitch diameter tolerance and h is height of sharp v thread. Metric threads coarse thread pitches 1 for metric threads pitch is the distance between threads.