July, 1913
T H E JOLTRLVALOF I S D C S T R I . 4 L A N D E-VGIiYEERISG C H E S l I S T R Y Parts per million
Free ammonia.. . . . . . . . . Alb. ammonia. . . . . . . . . . Nitrates. . . . . . . . . . . . . . . . Nitrites. . . . . . . . . . . . . . . . Chlorine, . . . . . . . . . . . . . . Oxygen consumed.. . . . . . Total solids.. . . . . . . . . . . . Colonies Der cc. . . . . . . . . .
B . Coli. . . . . . . . . . . . . . . . .
I
I1
111
0.02
0.05 0.10 2 .oo 0.005
0.10 0.15 2.50 0.01 20.0
0.08 1
.oo
0.000 2.00 1 .oo
100.0 100.0 0.00
10
.o
2 .oo 500.0 500 . o
Presence 10 cc. amts. Sediment . . . . . . . . . . . . . . . none slight Color . . . . . . . . . . . . . . . . . . none slight Odor . . . . . . . . . . . . . . . . . . none yes winter above 45 F . 40' F. Temperature . . . . . . . . . summer below 60' F. 80' F.
]
3-5 500-4000 1000-20,ooo
Presence 1/10 cc. amts. heavy yes yes very cold very warm
With increased attention to sanitary details everywhere, the manufacturer can well afford to add a clean, pure supply to his factory equipment. If it is impossible to obtain potable water, it should be prepared. I n case the supply is muddy, it should be filtered; if polluted it should be passed through sand and charcoal
or distilled and then passed through charcoal. I t must be remembered that water distilled from an impure source, organically, cames ammonia and sometimes other gases. Charcoal gives such water a pleasant taste and removes odor. Do not attempt to condense steam from an ordinary boiler for drinking purposes. Rather pass steam through - a copper _ - coil in a tin-lined kettle. Condense also in tin. Such water must be cooled before drinking. When a manufacturing corporation can afford to do so, it should build and operate its own water works. Ten, fifteen, or twenty miles is not a prohibitive distance to go for a good supply. The initial expense will be small compared with the additional resources of the plant that has all of the clean, soft water needed. To accomplish such a purpose, it may be necessary to buy several hundred acres of cheap land. This should be fenced and all people and animals kept out. Having an abundant supply, a corporation may add to its income by selling water. If water of a poor quality, but soft, is available near the concern, a purification plant on a large scale can be built to good advantage. Here water may be filtered or softened to the degree required by the average use to which it is put. DILLAYE BUILDING SYRACUSE, . ' h Y. i
CURRENT INDUSTRIAL NEWS
I
B y W. A. HAMOR
THE EYNON-EVANS FLANGED BLOW-OFF VALVE A Philadelphia concern has placed on the market a n angle flanged blow-off valve, a n illustration of which is shown below. The principle involved is that of protecting the packing inside the shield before the grit, scale and other blow-off products are permitted to pass through the valve from the boiler. The lower end of the shield also acts as a valve, thereby permitting of the removal and inspection of the packing while the blow-off valve is in service with full boiler pressure. The body and yoke 13 are cast in one piece, and are made extremely heavy. A nickel ring, 3 , is secured in the iron body, the interior diameter of which is the same as that of the interior of the bronze shield 2 , forming a continuous surface for the reception of the packing. This packing is so placed in the ring 3 and shield z that it prevents leakage from the inlet to the outlet and around the stem: it can be adjusted or compressed by the nuts to the desired density while the valve is in service. The hand wheel 14 withdraws the pistons with packing from the ring 3 into the shield 2 . The shield z is operated by the wheel numbered I I.
Rotating the small wheel 14 causes the packing with its piston to rise or open until the shoulder on the follower piston strikes the bottom of the hub 12. The packing is now inside the shield 2, protected from the blow-off products. Rotation of the wheel 11 causes the shield z to rise until the shoulder, just below the thread, strikes the bottom of the threaded bushing 7. After having rotated the wheel 1 1 to open the valve, and it is now desired to close it, the shield is rotated until it strikes the ring 3 . The small wheel 14 is then rotated and the packing is returned to fit inside ring 3 , making, i t is claimed, the valve absolutely tight. To open, the small wheel is raised first; to close, the large wheel is lowered first.
THE INFLUENCE OF SULFUR ON THE STABILITY OF IRON CARBIDE IN THE PRESENCE OF SILICON. The value of the heat treatment of the iron-carbon alloys depends mainly upon the manner in which the cementite and pearlite carbide are affected. Especially is this so in connection with the alloys richer in carbon, such as the various cast irons, and Hatfield (Eng., 95, 683) therefore endeavored to make a thorough study of this phase of the subject, as a result of which he recorded some experiments made to ascertain the manner in which sulfur affects the stability of iron carbide. The influence of sulfur has received considerable attention from the time of Percy onwards, and it is now accepted that, providing the other constituents of normal cast irons remain constant', any considerable increase in sulfur results in an increase in the combined carbon content-in other words, the presence of carbon prevents the entire breaking down of the carbides during the cooling of the iron. I t is generally understood that in ordinary cast irons the amount of sulfur present (rarely exceeding 0.06%) has little influence upon the carbon. Wiist has published the results of some experiments which, however, showed that the influence of sulfur was increased by any decrease in the silicon content of the iron. These experiments are considerably amplified by the data contained in a quite recent paper by Coe (Brit. Foundrymen's Assw., 1912). Hatfield concludes from his experimental investigations that : ( I ) Sulfur increases the stability of iron carbide a t high temperatures. ( 2 ) I t is most probably the small percentage associated with the carbide crystals that accomplishes this action. ( 3 ) Coe's deduction that the sulfur separates as sulfide a t the freezing point is not strictly correct, as a small and essential proportion is apparently retained in the cementite carbide. (4) The action of sulfur is of a chemical nature, and Levy's suggestion that the action is mechanical and is attributable to the existence of sulfide films does not receive support. ( j ) Silicon in a large measure neutralizes this action of the sulfur, probably by forming a silicon sulfide. (6) Manganese neutralizes the action of the sulfur present in such materials as mentioned.
