Portland Oregon Fire Hydrant Specifications, 1922
Source:   City of Portland, Stanley Parr Archives and Records Center, Water Bureau, Subject Files, A2001-021, 15/1   "Hydrants", 1919-1923


SPECIFICATIONS FOR FIRE HYDRANTS

  1. No experimental or untried type of fire hydrant will be accepted. The contractor, therefore, must be able to prove that the type of fire hydrant proposed by him has been in actual use for at least five (5) years in a water works system and has proven satisfactory.
  2. SIZE
    1. The size of hydrants shall be designated by the nominal diameter of the valve opening which must be at least 4" for hydrants having two (2) 2½ inch hose connections, and 6" for hydrants having three (3) 2½" hose connections, and 6" for hydrants having four (4) 2½ inch hose connections. Any hydrant having valve openings of shapes other that circular, the designation of size, must be the diameter of the circle equal in area to that of the valave opening, which area shall not be less than for the following sizes; 4" - 12.566 square inches; 5" - 19.635 square inches; 6" - 28.274 square inches. These areas must be maintained as a clear water way through the gate openings, in excess of the gate, rod and other appurtenances in the bottom of the hydrant.
    2. The net area of the water way at the smallest part when the hydrant is wide open must not be less than that of the valve opening and there must be sufficient clear water way through the hydrant when wide open to allow the passage of a solid ball at least 2" in diameter for a hydrant with a 4" valve opening and 2-3/8" in diameter for a hydrant with 5" or 6" valve openings.
    3. The inside diameter of the standpipe of hydrants shall not be less than 5-7/8", 6-7/8" and 8" respectively for hydrants having 4", 5" and 6" valve opening.
    4. The hydrants must be fitted with bell ends to fit standard pipe, or if flanged they must be fitted with flanges of standard dimensions, having standard layout for drilling, for pipes to be used under 80 lbs. pressure. Four inch valve opening hydrants shall be made suitable to connect to either 4" or 6" pipe as may be ordered and the 5" inch and 6" inch valve opening hydrants shall be made suitable to connect to either 6" or 8" pipe as may be ordered.
  3. GENERAL DESIGN
    1. Any changes in diameter of the water passage throughout the hydrant must have easy curves, and all outlets must have rounded corners of good radius.
    2. Hydrants must be so designed that with ordinary usage they will not cause water hammer.
    3. Valves when shut must remain tight when the upper portion of barrel is broken off.
    4. Hydrants are to be of the compression type.
  4. MATERIALS
    1. The metal for all iron castings must be of good quality, strong, tough and of even grain, and soft enough to satisfactorily admit of drilling and machining. The metal must be made without and admixture of cinder iron or other inferior metal, and must be remelted in a cupola or air furnace. The castings must be smooth, clean and perfect without blow or stand holes or defects of any kind. No plugging or filling will be allowed.
         Specimen bars of the metal used, each being 26 inches long by 2 inches wide and 1-inch thick must be made without charge as often as the Inspection Department may direct, and in default of definite instructions the manufacturer must 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, must support a load of 2,200 pounds, and show a deflection of not less than .35 of an inch before breaking; or if preferred, tensile bars may be made which must show a breaking point of not less than 22,000 pounds per square inch, bars to be cast as nearly as possible to the dimensions without finishing, but corrections may be made by the Inspection Department for variations in width and thickness, and the corrected result must conform to the two requirements.
    2. All wrought iron used must be of the best quality of double refined iron, of a tensile strength of at least 50,000 pounds per square inch.
    3. All composition metal used must be of the best quality, to have a tensile strength of not less than 28,000 pounds per square inch, with 18% elongation in a test bar of 2" and 5% reduction of area at breaking point. Composition for the main operating stem as well as the inside hose valve stems must have a tensile strength of not less than 55,000 pounds per square inch and an elastic limit of not less than 25,000 lbs. per square inch.
  5. HOSE NIPPLES AND VALVES
    1. Hose nipples must be of bronze threaded with a fine thread into the hydrants.
    2. 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 1911 National Standard adopted by the National Fire Protection Association.
    3. Where independent hose gates are required, the inside type must be used and must have composition metal working parts and be of rugged design, and must not introduce an unnecessary friction loss. There must be ample clearance between the gates and the hydrant body when the gate is in any position. The gate and parts are to be interchangeable and the valve shall be located so as to be accessible as possible for repairs. The gate must be so designed that it cannot become detatched from the stem or stem nut while in use. The top of the stem must be below the level of the hydrant stem nut so that the hydrant can be freely operated. Hose nipples must be of bronze threaded with a fine thread into the hydrant and it must extend through the hydrant standpipe so as to form the seat for the independent gate.
    4. The stems of the hose valves must be not less than ¾ of an inch in diameter for the 2½ inch valves, and not less than 7/8 of an inch in diameter for the valves at the steamer connections.
  6. HYDRANT SEAT AND GATE
    1. The seat must be made of bronze or a suitable non-corrosive composition, securely fastened in place.
    2. The valve must be faced with a yielding material, such as rubber or leather. The valve must be designed so that it can be easily removed for repairs without digging up the hydrant.
  7. DRIP VALVE
    1. A positively operating non-corrodible drip valve must be provided and arranged so as to completely drain the hydrant when the main valve is shut.
    2. The seat of the drip valve must be made of a non-corrodible material and must be securely fastened in the hydrant. All other parts of the drip mechanism must be designed to be easily removed without digging up the hydrant.
  8. OPERATING PARTS
    1. 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 material consisting of either Tobin or Phosphorous Bronze and both must be of rugged design and sufficiently strong to perform the work for which they are intended.
    2. The stem must terminate at the top in a nut of pentagonal shape finished with a slight taper to 1½ inches 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 hydrant must have the same operating nut as the old ones for uniformity. The nut socket in the wrench must be made so as to be reversible.
  9. STUFFING BOX AND GLAND
    1. The stuffing box and gland must be of bronze. When a packing nut is used, it must be made of bronze. The bottom of the box and end of the gland or packing nut must be slightly beveled.
    2. Gland bolts or studs must be at least ½ of an inch in diameter.
    3. Gland bolts or studs must be of bronze with bronze nuts.
  10. HYDRANT TOP
    1. The hydrant top must be designed so as to make the hydrant as weatherproof as possible and thus overcome the danger of freezing the stem. Provision must be made for oiling, both for lubrication and to prevent corrosion. A reasonably tight fit should be made around stems.
    2. There must be cast on top of the hydrant in characters raised 1/8 of an inch, an arrow at least 2½ inches long and the word "Open" in letters ½ of an inch high and 1/8 of an inch in relief.
  11. HOSE CAPS
    1. Hose caps must be provided for all hose outlets and must be securely chained to the barrel with a chain not less than 1/8 of an inch in diameter.
    2. The hose cap nut must be of the same size and shape as the stem nut.
  12. MARKINGS
    1. The hydrant must be marked with the name or trade mark of the manufacturer. Such letters and figures to be cast on the hydrants above the ground line.
  13. TESTING
    1. Hydrants after being assembled must be tested to at least 300 pounds per square inch before leaving the factory. If the working pressure is over 150 pounds per square inch 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 the valve shut, in order to test the strength and tightness of the valve.
    2. Hydrants must be fully opened and closed before shipping in order to test the freedom and strength of the parts. This test must be made under as severe conditions as are liable to occur in actual service when using a hydrant wrench at least 17 inches long.
  14. DIRECTIONS TO OPEN
    1. Hydrants must open to the left (counterclockwise) 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 ones for the sake of uniformity.



Portland Oregon Fire Hydrants