i STEAM COAL - Clpdigital.org
i STEAM COAL - Clpdigital.org
i STEAM COAL - Clpdigital.org
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30 THE <strong>COAL</strong> TRADE BULLETIN.<br />
chamber bonnets, and EE are exhaust ports leading<br />
from the ends of the steam-chest direct to<br />
the main exhaust and closed by the reversing<br />
valves II. Thus in further explanation of the<br />
operation: C, the piston, is driven by steam admitted<br />
under the slide valve G, which, as it is<br />
shifted backward and forward, alternately connects<br />
opposite ends of ->the cylinder A with the<br />
live steam pipe and exhaust. This slide valve<br />
G is shifted by the auxiliary plunger F; F is<br />
hollow and filled with steam, which, issuing<br />
through a hole in each end, fills the spaces be-<br />
Fig. 3—Parts of Regular Horizontal Pumps.<br />
tween it and the heads of the steam chest in<br />
which it works. Pressure being equal at each<br />
end, this plunger F, under ordinary conditions.<br />
is balanced and motionless; but when the main<br />
piston G has traveled far enough to strike and<br />
open the reverse valve I, the steam exhausts<br />
through the port EE from behind that end of the<br />
plunger F which, immediately shifts accordingly<br />
and carries with it the slide valve G, thus reversing<br />
the pump. No matter how fast the piston<br />
may be traveling, it must instantly reverse on<br />
touching the valve I. In its movement the plunger<br />
F acts as a slide valve to close the port EE,<br />
and is cushioned on the confined steam between<br />
the ports and steam-chest cover. The reverse<br />
valves II are closed as soon as the piston C leaves<br />
them, by a constant pressure of steam behind<br />
them, conveyed direct from steam chest through<br />
the ports shown by dotted lines.<br />
Fig. 2 shows the Cameron water valve chest and<br />
arrangement of valves. The right-hand side is<br />
shown in full as it appears when the bonnet is<br />
removed and the left-hand side in section. The<br />
superiority of this valve chest lies in this accessibility.<br />
By simply removing one bonnet or cover<br />
the whole interior with every valve is plainly<br />
visible, turned inside out, so to speak, and not a<br />
speck of anything that may have lodged there<br />
can escape detection. The shelves or decks are<br />
bored out tapering, and the brass seats forced in.<br />
They can thus be readily taken out and renewed<br />
at any time. Each stem holds two valves, with<br />
their springs one above the other, so that by<br />
simply unscrewing one plug and pulling up the<br />
stem both are released. It<br />
will be noticed that the Cameron<br />
valve chest is placed<br />
close to the ground and beside<br />
the water piston, instead<br />
of above it. The valves<br />
are, therefore, so much nearer<br />
the water and the suction lift<br />
is reduced accordingly. Every<br />
pump has two suction openings,<br />
one on each side, and<br />
the discharge opening can be<br />
turned in any direction desired.<br />
Fig. 3 shows an arrangement<br />
of detail parts of the<br />
regular horizontal piston<br />
pump for general service; the<br />
construction of every part can<br />
readily be noted. A list of<br />
names and number of each is<br />
also given, being as follows:<br />
Fig. 4— Vertical Plunger<br />
Sinking Pump.<br />
101, steam cylinder; 102, steam chest; 103,<br />
steam chest plunger; 104, steam chest cover; 105,<br />
steam chest crank and nut; 106, steam chest crank<br />
handle; 107, steam chest, stuffing box bottom;<br />
108, steam chest, stuffing box cap; 109, slide valve;<br />
110, steam cylinder cover; 111, reversing valve;<br />
112, reversing valve bushing; 113, reversing valve<br />
cap; 114, reversing valve plug; 115, steam piston<br />
head; 116, steam piston head, or follower—the<br />
head has a taper hole and the follower a straight<br />
hole; 117. steam piston head; 118, steam piston<br />
follower; 119, steam piston follower; 120, steam<br />
piston packing ring, with wedge and spring;<br />
121, steam piston packing ring; 122, steam piston