PUMPS AND PUMP VALVES
Transcript of Locomotive Engineers And Firemen:
by Charles A Hoxie, 1876
 
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PUMPS AND PUMP VALVES

 All Engineers will agree that every engine should be provided with reliable pumps, capable of being worked either at a high or low rate of speed. It often happens that a freight Engineer is called upon to draw a passenger train over the road with an engine that has been accustomed to low speed. Inevitably he will lose time, and, when an explanation is required, complaint will be made that the engine did not make steam fast enough, and the pump did not work. In almost every case, the pump is the sole cause of the lost time and the lack of sufficient steam, for the engine cannot make steam steadily unless the pump works freely and uniformly. Some times, also, the engine will fail to make steam for a short distance. In such a case, if the pump be reliable, it maybe shut off, so that the steam can be kept up to the standard, enabling the Engineer to make his running time with little trouble. A good pump, in short, renders an Engineer’s duty pleasant under nearly all

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circumstances; while a poor one is continually getting him into trouble, damaging his engine and his reputation.
 The locomotive pump has three valves, two to force water into the boiler, and one called the check valve, to take the pressure off the branch or injector pipe, and render the pump less liable to get out of order. The Capacity of the pump is governed to a great extent by the lift of the valve, which should be so arranged that the lower or bottom valve will receive no more water than the middle and check valves will receive without causing too great pressure on the pump between the valves. When a pump is overhauled, the lower valve should be set with a lift of one-eight of an inch, the middle valve with three-sixteenths of an inch. These proportions will render the pump reliable for any work required of the engine, except for very slow running on a grade, when the left-hand pump should have a lower valve, with a quarter of an inch lift, and the others respectively a scant three-eighths and half an inch. This will

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give the engine a left-hand pump for a slow rate of speed, and a good pump to fall back upon, should the right-hand pump become disabled from any unforeseen cause. Pumps set in this way will do good service for thirty or forty thousand miles, a fair year’s work for and engine.
 The pumps should be packed hard enough to prevent leakage, yet not to hard. Some Engineers pack the pumps as hard as possible with the object of making the packing last six or eight months or perhaps a year. This is wrong. When a pump is thus packed, power is taken from the engine, it is liable to get out of line, the plunger wears out of shape, and creases are cut in it, which render tight packing thereafter an impossibility. Packing will occupy four times as much time, and it will not be any better when done, than if it had been packed with reasonable tightness and packed oftener. When ever a pump begins to leak it should be repacked. To insure reliability, pumps should be packed three or four times a year.
 The Engineer should see to it that the engine tank is kept clean at all times, that here

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are strainers in his hose, and that he has spare strainers and washers to go with them. When his engine is in the shop, he should satisfy himself that the hole in the boiler, through which the water is received from the pump, or check hole, is properly cleaned out. It often becomes corroded, and sometimes it is closed so that the pumps will not work. He should also satisfy himself, in overhauling the pump, that the valve-seat is above the opening in the cage. Occasionally it gets worn below, in which case the valve shows the proper lift by measure, but does not get the opening indicated by the measure, and hence will not work. In some pumps a strainer is connected to the lower part of the lower valve-seat, in the lower chamber. The bottom of this strainer is perforated about one-third of the length, and is, or should be, air-tight, above the perforations. If it is not air-tight, the pump will fail to work either partially or entirely. The bolts holding the pump to the frame should be examined for the detection of loosened nuts. When a pump is first put in an engine it is lined up by the guides, and often liners are used,

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which should be closely watched. The rings inside the barrel and outside of the plunger should not be permitted to wear so that the packing will work through between the plunger and the rings, as it will be likely to get entangled in the cages and cause trouble.
 Among the simple matters requiring watchfulness is the management of the pet-cock. When the foot-cock is opened for working the pump, the pet-cock should always be opened to let the air escape. The working of the pump is then know to a certainty, provided the hole in the pet-cock be large enough to throw a perfect stream which can be seen at night. The plugs in the pet and foot-cocks should work easy, These matters seem trifling, and many Engineers doubtless regard them as too trifling for consideration. Nevertheless their importance cannot be denied. If an Engineer, accustomed to his own  engine, is called upon at night to run one that is strange to him, it will often happen that when he starts and opens the foot-cock to start the pumps, and desires to open the pet-cock to test them, he finds that it

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will not open until loosened by a blow from a wrench or hammer. Then he is unable to see the light spray which issues, gets angry, and finally orders the Fireman to put on the lift hand pump. Down the steam will go before the right hand pump can be got in operation, with very little water in the boiler, and the Engineer is in serious trouble, which would have been avoided had the pet-cock been in proper condition, Every Engineer should look to these things with unceasing vigilance. It is the sleepless attention to the smaller matters that goes to make up the aggregate of duty well performed, and the neglect of them as truly marks the careless or incompetent.
 

Chapter 1 - Introduction 
Chapter 2 - Locomotive 
Chapter 3 - The Fireman
Chapter 4 - Advice to Young Engineers
Chapter 5 - Tramming and Center Marking
Chapter 6 - Adjusting Side and Main Rods
Chapter 7 - Pumps and Pump Valves
Chapter 8 - Cylinder and Cylinder Packing

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