Metric Bolt Thread Pitch

Here r min is minimum root radius t d2 is pitch diameter tolerance and h is height of sharp v thread.

Metric bolt thread pitch.

Metric threads coarse thread pitches 1 for metric threads pitch is the distance between threads. 1 0 pitch distance from thread to thread in millimeters. An example of a sae bolt size is 1 2x13x1. Thread pitch metric fasteners are specified with a thread pitch instead of a thread count.

The thread depth is 0 614 x pitch. The thread pitch is the distance between threads expressed in millimeters measured along the length of the fastener. As i explained at the top of the page metric bolt sizes are stated as diameter x distance between threads x length. 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.

The rest of the dimensions are tabulated values from the asme standard. Sae bolts will not thread perfectly into a metric nut or metric threaded hole. Thread pitch is the number of threads per inch. The thread angle is 60 o.

American or sae bolt sizes are expressed as diameter x thread pitch x length. The metric system s pitch is commonly viewed as the reverse of tpi in that it is the distance measured between two adjacent threads. 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. 20 length in millimeters see below this example illustrates how a coarse threaded screw may appear.

Bellow are iso din accepted thread pitch charts for commonly found metric fasteners. Functional diameter is a measure of the ability to assemble the thread. 8 nominal diameter in millimeters. M12 x 25 12 mm diameter coarse thread is assumed 1 75 mm 25 mm long.

Bolt depot common metric thread pitches standard fine super fine jis. Maximum rounded form minor diameter d 3max d 2max 0 5h 2r min 1 cos 60deg arccos 1 t d2 4r min. This bolt is one half inch in diameter has 13 threads per inch and is one inch long. For example a thread pitch of 1 5 means that the distance between one thread and the next is 1 5mm.

Bolts screws and studs with specified property classes coarse thread and fine pitch thread. 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.