GB489822A - A rigid floating roof for inflammable liquid storage tanks - Google Patents

Abstract

489,822. Tanks; valves. JONES, G. A. Oct. 15, 1937, No. 28149. Convention date, Nov. 25, 1936. [Classes 69 (i) and 135] A floating roof for tanks for storing inflammable liquids is formed of rigidly connected contiguous compartments or cells closed at the top and sides but open at the bottom. The roof shown is divided into such cells by main radial ribs 2, short radial ribs 5, and transverse partitions 3, 3a, the latter being formed by turneddown edges of the metal sheets forming the deck of the roof. The roof-joints are all welded, the ends of the ribs 2 being welded to a central dip-tube G and to discs 4, 9, which form central junction plates. A seal is provided between the roof and the tank wall by hair, fibre, bristle or other brushes 11, Fig. 3, set in two or more rows in stocks 12 having mitred &c. ends to form gas-tight joints when secured in a continuous ring round the skirt 7 by fixed and removable clips 14, 15. Between the rows are fixed metal or fabric diaphragms 13 with contacting or overlapping ends, and the tops of the brushes are protected by similarly arranged sheets 14a of bronze gauze. When lowered, the roof is supported on brackets 18, and, when it is over 30 feet in diameter, by means of hydraulic supports D comprising cylinders secured to the roof and having down wardly projecting rams which contact with stools 25 attached to the tank bottom. The cylinders are connected to a chamber F in which an air pressure is maintained above the liquid. To allow the air pressures in the cells 2 of the roof to be tested and adjusted, each cell is connected by a tube 47 to one of a series of ports arranged in one or more circular rows on the seat 43 of a valve, shown in Fig. 8. Rotation of a ported valve disc 41a allows any selected cell to communicate with a manometer 48 to indicate the pressure, which may be adjusted by admission of air through a valve 49. To allow the pressures in all the cells to be equalized the disc 41a is turned to a position in which an inclined face 50 formed on it rides up a similar face 51 on the seat 43, the disc being thus raised from the seat so that all the ports in the latter communicate.