In our sector we usually find different ways for referring to a same thing, and this may give some understanding difficulties. We are talking in this article to the different way to name dimensions of different brass thread fittings, commonly used for fitting metal pipes (iron, copper) and which usual dimensions provide one of the designations.

With a simple table we show some of the common naming, due to the different designations we can find in different countries, by historical reasons or because of the own product evolution.

Usual equivalences
Nominal Dimension (DN) Thread Dimension Usual Pipe Designation (internal x external)
6 1/8 5x10
8 1/4 8x13
10 3/8 12x17
15 1/2 15x21
20 3/4 20x27
25 1 26x34
32 1.1/4 33x42
40 1.1/2 40x49
50 2 50x60
65 2.1/2 66x76
80 3 80x90
100 4 102x114
125 5 127x140
150 6 152x165