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Cleaning and Inspection.
Section 12. All pipes and special castings shall be thoroughly cleaned and subjected to a careful hammer inspection. No casting shall be coated unless entirely clean and free from rust, and approved in these respects by the engineer immediately before being dipped. Coating.
Section 13. Every pipe and special casting shall be coated inside and out with coal-tar pitch varnish. The varnish shall be made from coal tar. To this material sufficient oil shall be added to make a smooth coating, tough and tenacious when cold, and not brittle nor with any tendency to scale off.
Each casting shall be heated to a temperature of 300 degrees Fahrenheit immediately before it is dipped, and shall possess not less than this temperature at the time it is put in the vat. The ovens in which the pipes are heated shall be so arranged that all portions of the pipe shall be heated to an even temperature. Each casting shall remain in the bath at least five minutes.
The varnish shall be heated to a temperature of 300 degrees Fahrenheit (or less if the engineer shall so order), and shall be maintained at this temperature during the time the casting is immersed.
Fresh pitch and oil shall be added when necessary to keep the mixture at the proper consistency, and the vat shall be emptied of its contents and refilled with fresh pitch when deemed necessary by the engineer. After being coated the pipe shall be carefully drained of the surplus varnish. Any pipe or special casting that is to be recoated shall first be thoroughly scraped and cleaned. Hydrostatic Test.
Section 14. When the coating has become hard, the straight pipes shall be subjected to a proof by hydrostatic pressure, and, if required by the engineer, they shall also be subjected to a hammer test under this pressure.
The pressure to which the different sizes and classes of pipe shall be subjected are as follows:
20-inch Diameter Less than
and Larger 20-inch Diameter Pounds per
Square Inch Square Inch Class A pipe...
300 Class B pipe
300 Class C pipe.
300 Class D pipe.
Section 15. The pipes and special castings shall be weighed for payment under the supervision of the engineer after the application of the coal-tar pitch varnish. If desired by the engineer, the pipes and special castings shall be weighed after their delivery, and the weights so ascertained shall be used in the final settlement, provided such weighing is done by a legalized weighmaster. Bids shall be submitted and a final settlement made upon the basis of a ton of 2,000 lb. Contractor to Furnish Men and Material.
Section 16. The contractor shall provide all tools, testing machines, materials and men necessary for the required testing, inspection and weighing at the foundry of the pipe and special castings; and should the purchaser have no inspector at the works, the contractor shall, if required by the engineer, furnish a sworn statement that all of the tests have been made as specified, this statement to contain the results of the tests upon the test bars. Power of Engineer to Inspect.
Section 17. The engineer shall be at liberty at all times to inspect the material at the foundry, and the moldings, castings and coating of the pipes and special castings. The forms, sizes, uniformity and conditions of all pipes and other castings herein referred to shall be subject to his inspection and approval, and he may reject, without proving, any pipe or other casting which is not in conformity with the specifications or drawings. Inspector to Report.
Section 18. The inspector at the foundry shall report daily to the foundry office all pipes and special castings rejected, with the causes for rejection Castings to Be Delivered Sound and Perfect.
Section 19. All the pipes and other castings must be delivered in all respects sound and conformable to these specifications. The inspection shall not relieve the contractor of any of his obligations in this respect, and any defective pipes or other castings which may have passed the engineer at the works or elsewhere shall be at all times liable to rejection when discovered until the final completion and adjustment of the witract; provided, however, that the contractor shall not be held liable for pipes or special castings found to be cracked after they have been accepted at the agreed point of delivery. Care shall be taken in handling the pipes not to injure the coating, and no pipes or other material of any kind shall be placed in the pipes during transportation at or any time after they have received the coating. Definition of the Word "Engineer."
Section 20. Wherever the word "engineer" is used herein it shall be understood to refer to the engineer or inspector acting for the purchaser and to his properly authorized agents, limited by the particular duties intrusted to them.
STANDARD SPECIFICATIONS FOR HYDRANTS AND VALVES
SPECIFICATIONS FOR HYDRANTS
1. Size CLASSIFICATION.- The size of hydrant shall be designated by the nominal diameter of the valve opening, which must be at least 4 inches for hydrants having two 27/2 inch hose nozzles; 5 inches for hydrants having three 21/2-inch nozzles; and 6 inches for hydrants having four 2/2-inch nozzles; and shall be classed as one-way, two-way, three-way or four-way, etc., according to the number of 27/2-inch hose outlets for which they are designed.
AREA OF WATER WAY.-- The net area of the hydrant at the smallest part, when the valve is wide open, must not be less than 120 per cent. that of the valve opening.
BELL ENDS OR FLANGE ENDS.--All hydrants must be fitted with bell ends to fit standard cast-iron pipe, or if flanged they must be fitted with flanges of the standard dimensions corresponding to the pressure under which they are to be used; connecting pipe or flange from main to hydrant in no case to be less in diameter than the valve opening. (The standards referred to are those adopted or that may be adopted by this Association.)
2. GENERAL DESIGN
CHANGE IN DIAMETER.--Any change in diameter of the water passage through the hydrant must have easy curve, and all outlets must have rounded corners of good radius.
WATER HAMMER.- Hydrants must be so designed, particularly as regards the pitch of the thread of the operating stem, that, when properly operated a water hammer will not be caused which will give an increased pressure to exceed the working pressure, when such pressure is over 60 lb., nor increase the pressure more than 60 lbs. when operated under less working pressure than 60 lb.
BROKEN HYDRANT.- Valve when shut must remain reasonably tight when upper portion of barrel is broken off.
Friction Loss.- With a 5-foot hydrant discharging 260 gallons per minute, through each 24-inch outlet, the total friction loss of the hydrant must not exceed 2 lb. for two-way, 3 lb. for three-way, and 4 lb. for four-way hydrants.
STRAPPING.–When requested, hydrants must be fitted with 2 lugs, so that the leaded joint underground can be strapped.
FLANGE JOINTS ABOVE GROUND.-When hydrant barrel is made in two sections, the upper flange connection must be at least 2 inches above the ground line.
Cast IRON.--All castings shall be made from a superior quality of iron, remelted in cupola or air furnace, though and even grain, and shall possess a tensile strength of 22,000 lb. per sq. in. The casting must be
clean and perfect, without blow or sand holes, or defects of any kind. No plugging or stopping of holes will be allowed.
SPECIMEN 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 0.35 of an inch, before breaking ; or, if preferred, tensile bars shall be made which shall show a breaking point of not less than 22,000 lb. per sq. in. Bars must 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 the above requirements.
WROUGHT IRON.-All wrought iron shall be of the best quality of refined iron of a tensile strength of at least 45,000 lb. per sq. in.
COMPOSITION METALS.-All composition or other non-corrodible metals used to be of the best quality, to have a tensile strength of not less than 32,000 lb. per sq. in., with a 5 per cent reduction of area at breaking point.
4. Hose NIPPLES AND VALVES Hose NIPPLES.—Hose nipples must be of bronze or suitable non-corrodible metal, either threaded with a fine thread into the hydrants and securely pinned in place, or carefully locked and caulked in place.
Hose THREADS.-Hose threads on all hydrants to be installed in any given community must of necessity be interchangeable with those already in service, but, where practicable threads should conform to the National Standard.
5. HYDRANT SEAT AND. GATE SEAT.—The seat must be made of bronze or 'suitable non-corrodible metal, securely fastened in place.
VALVE.—The valve must be faced with a yielding material, such as rubber or leather, except that, if of the gate type, a bronze ring may be used. The valve must be designed so that it can be easily removed for repairs without digging up the hydrant.
6. DRIP VALVE DRIP.-A positively operating non-corrodible drip valve must be provided and arranged so as to properly drain the hydrant when the main valve is closed. The seat for the waste valve, which must be fastened in the hydrant securely, must be made of non-corrodible material. A11 other parts of the drip mechanism must be so designed as to be easily removed without digging up the hydrant.
7. OPERATING PARTS OPERATING THREADS.—The operating threads of the hydrant must be so arranged as to do away with the working of any iron or steel parts against iron or steel. Either the operating screw or the operating nut must be made of non-corrodible metal, and sufficiently strong to perform the work for which intended.
Top Nur.—The stem must terminate at the top in a nut of pentagonal shape, finished with slight taper to 11/2-inch from point to flat, except for hydrants to be installed where existing hydrants have different shape or size of nut, in which case the additional hydrants must have operating nuts similar to the old one for uniformity. The nut socket in the wrench must be made without taper, so as to be reversible.
8. STUFFING Box AND GLAND STUFFING Box.-The stuffing box and gland must be of bronze or suitable non-corrodible metal, or bushed with bronze or suitable noncorrodible metal, when an iron or steel stem is used, or when an iron operating stem nut passes through the stuffing box. When packing nut is used, it must be made of bronze or suitable non-corrodible metal. The bottom of the box and end of the gland or packing nut must be slightly beveled.
GLAND BOLTS.--Gland bolts or stubs must be at least 12-inch in diameter. Bolts or studs may be either of bronze or suitable non-corrodible metal, iron or steel. The nuts must always be of bonze or suitable noncorrodible metal.
9. HYDRANT Top Top. The hydrant top must be designed so as to make the hydrant as weather proof as possible, and thus overcome the danger from water getting in and freezing around the stem. Provisions must be made for oiling, both for lubrication and to prevent corrosion. A reasonably tight fit should be made around the stems.
LETTERING.--There must be cast on top of the hydrant in characters raised 18-inch, an arrow at least 2/2 inches long, and the word "open" in letters 12 inch high and % inch in relief, indicating direction to turn to open the hydrant.
10. HOSE CAP Caps.-- Hose caps must be provided for all outlets, and must be securely chained to the barrel with a chain constructed of material not less than 16 inch in diameter.
Cap NiT.-The hose cap nut must be of the same size and shape as the top or operating nut.
WASHER IN CAP.--When requested by the purchaser, a leather, rubber or lead washer must be provided in the hose cap, set in a groove to prevent its falling out when the cap is removed.
11. MARKINGS MARKING.— The hydrant must be marked with the name or particular mark of the manufacturer. All letters and figures must be cast on the hydrant barrel above the ground line.