VOL. 53 No. 6

DECEMBER 1912

Plate XXXIII-Type K Freight Triple Valve (Diagrammatic View) Emergency Position.

Plate XXXIII of the New York Air Brake Series of the Locomotive Firemen and Enginemen's Magazine Educational Charts concludes the subseries of diagrammatic views of the Type K Freight Triple Valve by showing it with the operative parts in the EMERGENCY POSI

TION.

Full, serial emergency-brake action throughout a train can only be obtained after the brakes are fully released and the auxiliary reservoirs recharged to somewhat near the pressure in the brake pipe; but partial emergency can be obtained immediately after the brakes have started to release, and after a very light service application has been made. When an emergency application is desired, a quick and heavy reduction of brake-pipe pressure must be made.

Referring to Plate XXXIII, it will be assumed that all parts were originally in the FULL RELEASE AND RECHARGING POSITION, and that a sudden, heavy reduction of brake-pipe pressure had been made; brake-pipe air is in passages A and B, B, and chamber C on the left of main piston 6, and by the heavy reduction on the left of the piston the auxiliary-reservoir pressure in chamber K became so much the greater that it quickly forced piston 6 to the extreme left of its traverse, compressing graduating spring 8, and carrying with it main slide-valve 2 and graduating valve 4 to the positions shown in the plate. In this position, piston 6 seats on the leather gasket of the front cap, forming an airtight joint, and prevents leakage of air from the auxiliary reservoir to the brake pipe.

With slide valve 2 and graduating valve 4 in the positions shown, the slide valve has cut off communication between

the brake-cylinder connections and exhaust port Q to the atmosphere; and cavity P and ports R, M and S in the slide valve, and cavity N in the graduating valve have no part in this phase of triple-valve action.

Port U extending clear through the slide valve, now registers with port W in the slide-valve seat, permitting auxiliary-reservoir air from chamber K to flow to emergency piston 13 forcing the piston to the extreme left which unseats quickaction valve 11 thus relieving the pressure in chamber X and permitting brakepipe pressure to unseat check valve 1, the brake-pipe air then rushing past the check valve, through chamber X and past quick-action valve 11 into and through passage Z to passage J and the brake cylinder by way of the connection at BC; due to the large openings through ports U and W, auxiliary-reservoir pressure is admitted to the right of piston 13 in such quantity as to force the piston beyond the by-pass port, A-1, thus preventing the power on the right of the piston being disturbed before emergency action is complete. At the same time the end of slide valve 2 having partially uncovered port I in the slide-valve seat, auxiliary-reservoir air from chamber K flows through port I direct to passage J and the brake cylinder, altogether causing a quick and full application of the brake on the car to which the triple valve is attached.

When the pressure in the brake pipe and the auxiliary reservoir have become nearly equalized (and which is practically instantaneous), check valve 1 and quick-action valve 11 will be returned to their seats, respectively, by the coil springs bearing upon them, the seating of the check valve, 1, preventing any back leakage of air from the brake cylinder to the brake pipe. A somewhat higher braking power is obtained at emergency than at full service application, due to the vent of brake-pipe air into the brake cylinder. Consequently, as the brake cylinder and auxiliary reservoir become equalized in pressure at emergency application, it requires a slightly greater increase of brake-pipe pressure to release the brake than following a full service application.

The more important and desirable result from the vent of brake-pipe air at emergency application is in the impulse it gives to the continuity of serial emergency-brake action through the whole

train, as when one triple valve applies in emergency its vent of air so quickly reduces the brake-pipe pressure in the immediate vicinity that the triple valves on the cars adjoining are thrown on in emergency, and they in turn similarly affect those following, etc., this connec tive brake action taking place almost simultaneously on the cars throughout a long train.

Asbestos.

Although the United States led all the countries of the world in the conversion of raw asbestos into the manufactured product, less than 1 per cent. of the material used was mined in this country. The greatest part came from Canada. The total production of the United States for 1911, according to the Geological Survey, was valued at $119,935, while the raw material imported from Canada was valued at more than eleven times that amount.

Orders and Rulings of the Board of Railway Commissioners for Canada.*

Order No. 15630.

THE BOARD OF RAILWAY COMMISSION-
ERS FOR CANADA.

Tuesday, the 12th day of
December, A.D. 1911.

HON. J. P. MABEE,

Chief Commissioner.

S. J. MCLEAN,

Commissioner.

In the matter of the order of the Board No. 10462, dated May 3, 1910, directing that on or before June 1, 1911, all electric railway companies under the jurisdiction of the Board equip all rolling stock in use by them of 37 feet or over in length, or of the weight of 35,000 pounds or more, with power brakes, to be approved by the Board, in addition to hand brakes and proper standing appliances; and the orders of the Board No. 13619, dated May 9, 1911, and No. 14316, dated July 20, 1911, extending the time within which the said work be completed until the first August and the first November, 1911, respectively;

And in the matter of the application of the Canadian Pacific Railway Com*By Wm. L. Best, Canadian Legislative Repre sentative, B. of L. F. and E.