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12. TESTING TESTING.—Hydrants for pressures of 150 lb. or less, after being assembled, shall be tested by hydraulic pressure to 300 lb. per sq. in., before leaving the factory. If the working pressure is over 150 lb. per sq. in. the hydrants must be tested to twice the working pressure. The test must be made with the valve open in order to test the whole barrel for porosity, and strength of hydrant body. A second test must be made with valve shut, in order to test the strength and tightness of the valve.
13. DIRECTIONS TO OPEN OPENING.–Hydrants must open to the left (counter clockwise) except those to be installed where existing hydrants open to the right, in which case the additional hydrants must turn the same as the old one for the sake of uniformity.
SPECIFICATIONS FOR VALVES
CASTINGS Castings.-All iron castings shall be made from a superior quality of iron, remelted in cupola or air furnace, tough and of even grain, and shall possess a tensile strength of 22,000 lb. per sq. in. The castings must be clean and perfect, without blow or sand holes or defects of any kind. No plugging or stopping of holes will be allowed.
TEST BARS Test Bars.--Specimen bars of the metal used, each being 26 inches long by 2 inches wide and 1 inch thick, shall be made without charge as often as the engineer may direct, and in default of definite instructions, the contractor shall make and test at least one bar from each heat or run of metal. The bars when placed flatwise upon supports 24 inches apart, and loaded in the center, shall support a load of 2,200 lb., and show a deflection of not less than .35 of an inch before breaking; or, if preferred, tensile bars shall be made which will show a breaking point of not less than 22,000 lb. per sq. in. Bars to be cast as nearly as possible to the dimensions without finishing, but corrections may be made by the engineer for variations in width and thickness, and the corrected result must conform to above requirement.
NAME.--Each valve shall have the makers' name cast upon it.
WROUGHT IRON Wrought Iron.-All wrought iron used shall be of the best quality of refined iron, of a tensile strength of at least 45,000 lb. per sq. in.
COMPOSITION METALS COMPOSITION.---All composition metals to be of the best quality, and, except the stems, to have a tensile strength of not less than 30,000 lb. per sq. in., with 5 per cent elongation in 8 diameters, and 5 per cent reduction of area at breaking point.
FACE JOINTS Face JOINTS.---All joints shall be faced true and smooth, so as to make, with suitable gaskets, a perfectly watertight joint.
FITTING AND INTERCHANGEABLE PARTS FITTINGS.— The fitting of all parts must be such as make perfect joints and all parts of the valves of the same make and the same size shall be interchangeable. Valves to open as specified by the engineer.
BOLTS AND NUTS BOLTS AND NUTS.---All bolts and nuts in valves to be made from the best quality of double refined wrought iron or steel, heads, nuts and threads to be standard sizes.
KIND OF VALVES
KIND.- Valves shall be fully mounted with bronze or suitable noncorrodible metal, and be either of the double disc or made up gate type with bronze or suitable noncorrodible metal mounted wedging devices or have wedge-shaped gates with double faces and seats, designed to work equally well with pressure on either side of the gate. The gates (or discs) shall be of cast iron with bronze or suitable non-corrodible metal faces. These faces shall be machined, dovetailed and driven into corresponding machined grooves in gates (or discs) or riveted on with bronze or suitable noncorrodible metal rivets.
The seats for composition rings in body of valve shall be turned and threaded before rings are screwed in.
To BE WATER TIGHT SEAT AND GATE Rings. Both seat rings and gate (or disc) rings shall have smooth and true faces, and make a perfectly watertight joint.
Valves shall have hub ends suitable for laying with classes B and American Water Works Association standard pipe. All valves 24 inches in diameter and larger shall be geared.
BYPASSES.--Where bypasses are required, they shall, unless otherwise specified, be of the following sizes: 16-inch valve
3-inch bypass 18-inch and 20-inch valves 3-inch bypass 24-inch and 30-inch valves 4-inch bypass 36-inch and 42-inch valves 6-inch bypass 48-inch valves
Weight.–Valves without bypasses shall be approximately not less than the following weights for the respective sizes: 3-inch
67 lb. 4-inch
85 lb. 6-inch
180 lb. 8-inch
255 lb. 10-inch
400 lb. 12-inch
500 lb. 14-inch
780 lb. 16-inch
900 lb. 18-inch
1,290 lb. 20-inch
1,700 lb. 24-inch, geared
2,750 lb. 30-inch, geared
5,200 lb. 36-inch, geared
8,500 lb. 42-inch, geared
12,000 lb. 48-inch, geared
VALVE STEMS STEMS.— l'alve stems shall be made of solid brass or suitable noncorrodible metal, free from defects, and shall have a terísile strength of not less than 45,000 lb. per sq. in.
THREADS.-Threads on stems to be square, acme or 12 V, and cut in most perfect manner, so as to work true and smooth and in perfect line throughout the lift of the valve.
Size of STEMS.-Valve stems at the bottom or base of the thread shall not be less than the following sizes in diameter: 3-inch valve
44/64 inch 4-inch valve
55/64 inch 5-inch valve
55/64 inch 6-inch valve
1 inch 7-inch valve
1 inch 8-inch valve
1 inch 9-inch valve
1 8/64 inch 10-inch valve
1 8/64 inch 12-inch valve
112/64 inch 14-inch valve
112/64 inch 16-inch valve
1 28/64 inch 18-inch valve
1 28/04 inch 20-inch valve
1 48/64 inch 22-inch valve
1 48/64 inch 24-inch valve
1 62/64 inch 30-inch valve
212/64 inch 36-inch valve
2 32/64 inch 42-inch valve
2 48/64 inch 48-inch valve
3 32/64 inch Wrench Nut.—The wrench nut on stem shall be inches square with arrow cast on showing direction which valve is to turn to open.
PAINTING PAINTING.—All iron work, after being thoroughly cleaned, to be painted throughout with asphaltum varnish, or suitable paint, or dipped in suitable coating material.
TESTING Testing.–Valves must be tested for leakage and distortion as follows: On double disc or made up gate type, the body of the valve shall be drilled and tapped with a hole for pipe and a removable plug inserted, through this hole a hydraulic pressure of 300 lb. per sq. in. shall be applied; the wedge-shaped gate type by an hydraulic pressure of 300 lb. per sq. in. applied, first between one end and the gate, second between the opposit end and the gate, and third in the bonnet with gate open.
UNIVERSITY WORK OF INTEREST TO RAILWAY WATER
R. C. BARDWELL, Chairman; C. R. KNOWLES, Sub-Committee.
Communication from Prof. G. A. Young, head of Mechanical Engineering at Purdue University, to the President of this Association relative to work of interest on water treatment in progress at the university, was forwarded to this Committee for establishing contact and report.
Investigation developed that during the school year 1920-1921, study on this subject was started under the direction of H. Ruebenkoeing, Professor of Railway Mechanical Engineering. To date a large bibliography on water treatment has been collected and abstract prepared. Further work and study is contemplated when facilities become available.
Work of further interest in connection with water treatment under varying heat conditions is being conducted under the direction of Dr. Edward Bartow, head of the Chemistry Department, University of Iowa, Iowa City, Iowa. Considerable data has been secured, but the results are not as yet ready for publication.
During the year 1919-1920, investigation of interest in connection with study of the electrolytic phase of pitting and corrosion was carried on by D. A. Steel at the University of Montana, Bozeman, Montana. The work indicated that the injurious effects caused by the presence of varying amounts of the common electrolytes, sodium sulphate and sodium chloride, can be inhibited by the presence of definite proportions of various hydrates and alkaline salts. The results secured are not sufficiently definite for authoritative publication, and it is suggested that further investigation be carried out along these lines.
Recent work of interest on the subject of "The Self-Corrosion of Cast-Iron and Other Metals in Alkali Soils" was carried out by W. Nelson Smith and Dr. J. W. Shipley at the University of Manitoba, Winnipeg, Canada, results of which have been published in the October, 1921, issue of the Journal of the Engineering Institute of Canada.
Advice has been received that study and investigation is contemplated at the Chemical Laboratory of the Sheffield Scientific School, Yale University, under the direction of W. T. Read, who was author of the University of Texas Bulletin 1752, published under date of September 15, 1917, on “Boiler Waters, Their Chemical Composition, Use and Treatment," which has been a valuable addition to the compilation of information on this subject. Revision of the work covered by this bulletin with inclusion of further information is a possibility.
This Committee fully realizes the importance of research work as carried out by the various universities throughout the country and appreciates the value of such work to the railroads. The facilities available at our universities for carrying on this work together with the scientific personnel in charge, give assurance of development of ideas and conclusions of practical value. With the approval of the Association your Committee will be pleased to keep in touch with this matter and report developments from time to time.