Fig. 304 _shows the Worthington Admiralty pattern boiler feed pump_ which is designed to meet the requirements of the United States Bureau of Steam Engineering for steam boiler pressure up to 250 lbs. to the square inch. The ordinary slide valves are replaced by piston valves with outside, adjustable, lost-motion links, making it possible to readily adjust the stroke. The water end is made of composition, gun metal, or cast-iron, as desired. When made of cast iron the water end is brass-fitted throughout. TABLE OF SIZES, CAPACITIES, ETC. ===========+===========+========+================= | | | Horse-power | | | of Boiler based | | | on 45 pounds of | | | water per hour, | | | which this Diameter of|Diameter of| Length | pump will Steam | Water | of | supply at Cylinders | Pistons | Stroke | slow speed. -----------+-----------+--------+----------------- 4-1/2 | 2-3/4 | 4 | 170 5-1/4 | 3-1/2 | 5 | 280 6 | 4 | 6 | 470 | | | 6 | 4-1/2 | 6 | 590 7-1/2 | 5 | 6 | 670 9 | 6 | 6 | 960 | | | 7-1/2 | 4-1/2 | 10 | 800 9 | 6 | 10 | 1400 10 | 7 | 10 | 2200 | | | 12 | 8-1/2 | 10 | 3200 12 | 9-1/4 | 10 | 3800 14 | 10 | 15 | 4800 -----------+-----------+--------+-----------------