The taper of the threads is 1/16 inch in diameter for each inch of length or 3/4 inch per foot.
WHITWORTH'S SCREW THREADS FOR GAS, WATER, AND HYDRAULIC IRON PIPING.
NOTE.--The Internal and External diameters of Pipes, as given below, are those adopted by the firm of Messrs. JAMES RUSSELL & SONS, in Pipes of their manufacture.
+---------------------------------------+ | GAS AND WATER PIPING. | +-------------+-------------+-----------+ | Internal | External | No. of | | Diameter of | Diameter of | Threads | | Pipe. | Pipe. | per Inch. | +-------------+-------------+-----------+ | 1/8 | .385 | 28 | | 1/4 | .520 | 19 | | 3/8 | .665 | 19 | | 1/2 | .822 | 14 | | 3/4 | 1.034 | 14 | | 1 | 1.302 } | | | 1-1/8 | 1.492 } | | | 1-1/4 | 1.650 } | | | 1-3/8 | 1.745 } | | | 1-1/2 | 1.882 } | | | 1-5/8 | 2.021 } | | | 1-3/4 | 2.047 } | | | 1-7/8 | 2.245 } | | | 2 | 2.347 } | | | 2-1/8 | 2.467 } | | | 2-1/4 | 2.587 } | 11 | | 2-3/8 | 2.794 } | | | 2-1/2 | 3.001 } | | | 2-5/8 | 3.124 } | | | 2-3/4 | 3.247 } | | | 2-7/8 | 3.367 } | | | 3 | 3.485 } | | | 3-1/4 | 3.698 } | | | 3-1/2 | 3.912 } | | | 3-3/4 | 4.125 } | | | 4 | 4.339 } | | +-------------+-------------+-----------+
+----------------------------------------------------+ | HYDRAULIC PIPING. | +----------+----------+------------------+-----------+ | Internal | External | Pressure in lbs. | No. of | | Diameter | Diameter | per Square | Threads | | of Pipe. | of Pipe. | Inch. | per Inch. | +----------+----------+------------------+-----------+ | | { 5/8 | 4,000} | | | 1/4 | { 3/4 | 6,000} | 14 | | | { 7/8 | 8,000} | | | | { 1 | 10,000} | | | | | | | | | { 3/4 | 4,000} | | | 3/8 | { 7/8 | 6,000} | 14 | | | { 1 | 8,000} | | | | { 1-1/8 | 10,000} | | | | | | | | | { 1 | 4,000} | 14 | | 1/2 | { 1-1/8 | 6,000} | | | | { 1-1/4 | 8,000 } | 11 | | | { 1-3/8 | 10,000 } | | | | | | | | | { 1-1/8 | 4,000 | 14 | | 5/8 | { 1-1/4 | 6,000} | | | | { 1-3/8 | 8,000} | 11 | | | { 1-1/2 | 10,000} | | | | | | | | | { 1-1/4 | 4,000} | | | 3/4 | { 1-3/8 | 6,000} | 11 | | | { 1-1/2 | 8,000} | | | | { 1-5/8 | 10,000} | | | | | | | | | { 1-3/8 | 4,000} | | | 7/8 | { 1-1/2 | 6,000} | 11 | | | { 1-5/8 | 8,000} | | | | { 1-3/4 | 10,000} | | | | | | | | | { 1-1/2 | 4,000} | | | 1 | { 1-5/8 | 6,000} | 11 | | | { 1-3/4 | 8,000} | | | | { 1-7/8 | 10,000} | | | | | | | | | { 1-5/8 | 4,000} | | | 1-1/8 | { 1-3/4 | 6,000} | 11 | | | { 1-7/8 | 8,000} | | | | { 2 | 10,000} | | | | | | | | | { 1-3/4 | 4,000} | | | 1-1/4 | { 1-7/8 | 6,000} | 11 | | | { 2 | 8,000} | | | | { 2-1/8 | 10,000} | | | | | | | | | { 1-7/8 | 4,000} | | | 1-3/8 | { 2 | 6,000} | 11 | | | { 2-1/8 | 8,000} | | | | { 2-1/4 | 10,000} | | | | | | | | | { 2 | 4,000} | | | | { 2-1/8 | 6,000} | | | 1-1/2 | { 2-1/4 | 8,000} | 11 | | | { 2-3/8 | 10,000} | | | | { 2-1/2 | 10,000} | | | | | | | | | { 2-1/8 | 4,000} | | | 1-5/8 | { 2-1/4 | 6,000} | 11 | | | { 2-3/8 | 8,000} | | | | { 2-1/2 | 10,000} | | | | | | | | | { 2-1/4 | 3,000} | | | | { 2-3/8 | 4,000} | | | 1-3/4 | { 2-1/2 | 6,000} | 11 | | | { 2-5/8 | 8,000} | | | | { 2-3/4 | 10,000} | | | | | | | | | { 2-3/8 | 3,000} | | | | { 2-1/2 | 4,000} | | | 1-7/8 | { 2-5/8 | 6,000} | 11 | | | { 2-3/4 | 8,000} | | | | { 2-7/8 | 10,000} | | | | | | | | | { 2-1/2 | 3,000} | | | | { 2-5/8 | 4,000} | | | 2 | { 2-3/4 | 6,000} | 11 | | | { 2-7/8 | 8,000} | | | | { 3 | 10,000} | | +----------+----------+------------------+-----------+