Metric Tapered Thread DIN 158

The metric tapered thread according to DIN 158 is intended for pipe fittings and is used, for example, on plug screws and grease nipples. According to the updated standard 158-1, only the external thread is tapered. It is combined with a cylindrical internal thread according to DIN 13. This results in a metallically sealing connection, which at least for small diameters also seals well without additional sealing materials. For connections with larger nominal sizes, the use of sealing materials is recommended, as the sealing properties decrease with increasing diameter.

The DIN 158 metric tapered thread has a flank angle of 60° and a taper of 1:16.

The thread designation consists of four components: the abbreviation M, the external diameter in mm, the pitch in mm, and the addition "keg" to distinguish it from cylindrical metric threads. An M 6 x 1.0 keg is a metric tapered thread with a 6 mm external diameter and 1 mm pitch.

The thread table for the DIN 158 metric tapered thread lists the external diameter, core hole diameter, and pitch in mm. Sometimes, several different pitch values are assigned to one external diameter. In addition to the tapered external thread, you can refer to the thread table for the metric thread according to DIN 13 for the cylindrical internal thread. Dies and taps for the DIN 158 metric tapered thread are available in many common sizes in our online shop; click on the links in the table.