Pumps and Hydraulics, Part 1 (of 2)

by N. Hawkins

Fig. 304.

In the plunger and ring pattern, [Fig. 302], there is a double-acting plunger, B, working through a deep metallic ring bored to fit the plunger. The plunger is located some inches above the suction valves, leaving a settling chamber, into which any foreign substance may fall out of the way of the wearing surfaces. Both the plunger and ring can be taken out and either refitted or, when necessary, renewed. The valves consist of small discs of rubber, or other suitable material, and are easily accessible through convenient handholes. This pattern is recommended where the liquid to be pumped contains small quantities of grit or foreign material, or where there is an unusually long or high suction lift.

In the piston-pattern pump, [Fig. 303], there is a packed water piston, G, working in a brass-lined cylinder, H. Both the suction and the discharge valves are located above the water pistons, so that the pistons may be at all times submerged. This pattern is recommended where the liquid to be pumped contains no grit or foreign material.

[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.

Diameter of Steam Cylinders	Diameter of Water Pistons	Length of Stroke	Horse-power of Boiler based on 45 pounds of water per hour, which this pump will supply at slow speed.
41⁄2	23⁄4	4	170
51⁄4	31⁄2	5	280
6	4	6	470
6	41⁄2	6	590
71⁄2	5	6	670
9	6	6	960
71⁄2	41⁄2	10	800
9	6	10	1400
10	7	10	2200
12	81⁄2	10	3200
12	91⁄4	10	3800
14	10	15	4800
Diameter of Steam Cylinders	Diameter of Water Pistons	Length of Stroke	Sizes of Pipes for Short Lengths To be enlarged as length increases.
			Steam Pipe	Exhaust Pipe	Suction Pipe	Delivery Pipe
41⁄2	23⁄4	4	3⁄4	11⁄4	2	2
51⁄4	31⁄2	5	1	11⁄2	21⁄2	21⁄2
6	4	6	11⁄2	2	4	3
6	41⁄2	6	11⁄2	2	4	3
71⁄2	5	6	11⁄2	2	5	4
9	6	6	2	21⁄2	5	4
71⁄2	41⁄2	10	11⁄2	2	4	3
9	6	10	2	21⁄2	5	4
10	7	10	2	21⁄2	6	5
12	81⁄2	10	21⁄2	3	6	5
12	91⁄4	10	21⁄2	3	6	6
14	10	15	21⁄2	3	8	6
Diameter of Steam Cylinders	Diameter of Water Pistons	Length of Stroke	Approximate Space Occupied Inches
			Height	Depth	Width
41⁄2	23⁄4	4	38	18	23
51⁄4	31⁄2	5	46	22	29
6	4	6	50	23	32
6	41⁄2	6	50	23	32
71⁄2	5	6	54	28	33
9	6	6	57	27	36
71⁄2	41⁄2	10	66	28	33
9	6	10	68	27	36
10	7	10	77	34	40
12	81⁄2	10	86	39	44
12	91⁄4	10	86	39	44
14	10	15	110	36	50

A notable feature in this pump is the location of the exhaust passage; this opening is underneath the cradle—or the part that the pump rests upon—just forward of the steam cylinders. The flanges of the steam end and cylinders and the steam chest cover have been made heavier than the regular and strengthened to withstand the higher pressures.