Kromdraai Gold Mine General artefacts in the museum (Image: Gauteng Tourism Authority) Gold is central to the history of Gauteng and it was only as recently as 1886 that the city of Johannesburg was founded, mainly due to the vast amounts of gold to be found in the area.
3000 yards on each spool of dark pink thread. Ideal for light to medium weight structured fabrics. â¢ Shrink and abrasion resistant.
But, to actually determine the size of a pipe, the outside diameter of each pipe or fitting must be measured and compared to the table for size identification. For example, a 3/4 NPT pipe thread has an outside diameter of 1.050 inches. Each thread size has a defined number of threads per inch (TPI). The 3/4 NPT pipe thread has 14 threads per inch. Both the TPI (threads per inch) and OD (outside diameter) of the thread are required for positive identification of thread size because several sizes have the same TPI.