after the steam has circulated through the radiator coil its drainage is piped down through the floor, connecting again with the trap body at "drip," the condensation flowing down past valve D, onto the disc X, passes around the edges of the latter and is let out through the openings in the bottom of basket; when the drip water becomes hot enough to expand disc X, valve D will be closed, with the effects as already understood in the pressure system; but valve C on the upper end of the main stem will not have been moved up far enough to reduce the pressure supply to the radiator coil at all; the later cooling of the disc and re-opening of valve D is a matter with which the student is already familiar. If, now, a less powerful but more equable heat is desired, the vapor system can be instantly initiated by simply screwing the wheel handle until valve B is closed-see now, Fig. 4. The large valve on the lower end of stem B, having seated, no steam can now flow to the train pipe except through the angle port within the valve, and the valve has been brought down so low that when the trap disc expands, the upward movement of the main stem will close valve C before the automatic drip-valve D can reach its seat Fig. 5. Consolidated Car Heating Co.'s Drum Hot Water System. Plan of Piping Passenger Car Two Circuits, Four No. 169U Drums and the latter remains permanently open. Steam from the train pipe having been admitted by the opening of inlet valve A, it flows to and through the radiator coil in the manner already explained with reference to the pressure system, and, likewise, after the radiator coil is heated the drip water spilling from the trap basket expands the disc and raises the main valve stem; but here the similarity in action ends; valve C closes and shuts off the supply of steam from the radiator coil, until the disc having again cooled and contracted, the valve re-opens the steam supply, and so on. As shown in the cuts, both automatically acting valves are protected against the entrance of scale, etc., by perforated metal strainers. The range between the opening and closing of these valves can be adjusted by turning the nut, J, and clamping the screw in position by the lock nut. This trap can be substituted in place of the common pressure traps with practically no change of piping. Other Combination Systems of Train Heating. 7. Water Circulation in Radiators, Heated Either by Steam from Locomotive or Fire in Car Stove.-All makers of steam-heating equipment furnish MES CAR-HEATIN Fig. 6. Hot Water Drum. Consolidated Drum No. 169U combination systems using hot water as the circulating medium, which is heated by steam while the locomotive is attached to the train, and heated by the coils in a Baker heater when not in connection with a locomotive or steam supply in the coach tracks. Fig. 5 illustrates the Consolidated Car Heating Co.'s Two-Circuit, Hot-Water Drum system. It is very much the same as the Baker Heater with Steam Attachment described in connection with Fig. 13 (Part 1), the drums here corresponding with the steam jackets in the Baker system: with the difference that the latter contains the steam, and the water circulates through the inner pipes; while in the Consolidated system the main outer drum contains the water of circulation, and the steam flows through the inner pipes. Fig. 6 shows the hot water drum quite plainly; the body of the drum encloses four brass radiator pipes which extend its entire length and are securely plugged at the end; inside each radiator pipe is a smaller brass pipe somewhat shorter than the former, and open at the end. Steam from the train pipe enters the steam port, and passing through the small interior pipes returns through the large exterior ones, leaving the drum through the drip port. Water of the main circulatory system entirely surrounds the radiator pipes in the drum. The water ports of the drum are so located that the circulation always assumes a natural course by entering the lower port and passing out the upper port; this also permits drainage of the drum from a horizontal or vertical position. Four such drums are used in the system as shown in Fig. 5, Nos. 169U, in the cut-two placed horizontal, and two vertical. The student being familiar with the Baker systems, but little additional explanation is necessary beyond that already given here and that on the cut, Fig. 5. There are two distinct water circulation systems, with two separate expansion drums. There is but one steam inlet valve-No. 100U-located in the heater room, and when opened steam from the train pipe flows through a branch pipe terminating in a tee from which two other branch pipes convey the steam to the bottom of the two vertical drums from which, after circulating in the radiator pipes and heating the water in the drums, it flows from the bottom of the drums into the return pipes which again unite as one pipe, and continues to and through each of the horizontal drums beneath the floor, flowing finally to the trap which automatically discharges the condensation, as already understood. There are two special features in this system which are of value; one is the current director, No. 59R in Fig. 5, and shown in section in Fig. 7. It will be noticed that the riser and delivery pipes do not enter the expansion drum separately; in order to secure positive circulation they unite in 59R, and (see sectional) pipe F is screwed into the bottom of drum, with pipe C extending inside of pipe F, to a higher altitude in the drum; the heater water from drum or fire pot, entering by the side opening in 59R, acts on the principle of the injector jet to expedite the downward flow of the water toward the car-heater coils. The special filler cock-see Fig. 8-is located in the system at 121 in Fig. 5, and its use was explained in the Baker heater system; but here, connection with a single crossover pipe only, is necessary. Referring to the sectional view, the cock in the main body of valve is of the butterfly style, and is ordinarily open; two common plug cocks, normally closed, are connected one on each side of the main cock. When it is desired to flush out the pipes or to fill them, the main cock, B, is closed, the other two are opened and water is pumped into the system through one of them, the drainage flowing from the other, cock B separating the piping system at that point-between the inlet and outlet of the water. The principle difference between the various combination systems is only in the methods by which the steam is made to heat the water of circulation. Fig. 9 shows the main essentials of the Gold combination system, and is self explanatory. The Baker heater coils in the firepot contain the steam radiating pipes coiled within them. From the inlet valve, train-pipe steam flows through these interior pipes in the coils-when there is no fire in the heater-where the water contained in the larger pipes is heated and rises to the expansion Fig. 8. Consolidated Car Heating Co.'s Special Filler Cock. drum, to start the circulation throughout the car, the steam then flowing to the drip pipes from the lower connections of the firepot coils, to the trap beneath the car, as is understood. So, in this case the water is always heated in the Baker heater, whether by fire, or by steam. The sealed jet fitting A, performs similarly to the current director in the system previously explained, and is shown so plainly as to need no further description. 8. The Commingler System.-The Commingler system in which, the well known Baker heater is supplemented by steam from the locomotive, is essentially different from other combination systems in that when steam is used, it heats the water of circulation by mingling directly with it. The heat-radiating coils throughout the car are of the usual Baker heater style, and the drip pipe from the steam equipment terminates in a hot metallic contact with the train pipe (Consolidated Car Heating Co.'s patent), to prevent possibility of the drip freezing up. Fig. 10 represents those parts which may be considered original in this system, and comprises only the devices not already understood in the combination systems. The dial cock corresponds to the common, steam inlet-valve; the trap cock is peculiar to this system, and is used to regulate or close off the flow of condensation to the drip pipe. |