GB973773A - Improvements in or relating to methods and apparatus for clearing and reconditioning road gulleys - Google Patents

Abstract

973,773. Pneumatic refuse collectors. JOHNSTON BROTHERS (ENGINEERING) Ltd., H. G. SMALLWOOD, and P. B. HIRST. Feb. 6, 1963 [Nov. 8, 1961], No. 28649/61. Heading E1G. [Also in Division F1] A method of cleaning a road gulley 40 consists in progressively lowering into it from the ground level to the gulley bottom the lower end of a suction conduit 38 at such a rate that the end is maintained from ¢ to 1 inch above the liquid level therein, the conduit 38 being connected to a reduced pressure source of substantially constant value so as to produce an air velocity of not less than 15,000 ft. per min. at the entry to the end, the liquid being thus drawn up into the conduit 38 with the air, and also the sludge and solids at the bottom when the conduit 38 reaches them, with or without plunging the conduit end into them. An apparatus to carry out the method comprises a vehicle on which is mounted a container 10, communicating with the low pressure side of a motor-driven rotary bladed air suction pump 17 and with a suction conduit 38, at the inlet end of which an air suction pump 17 produces a velocity of 15,000 ft. per min. and which may be lowered vertically from the ground level to the gulley bottom. Preferably the conduit diameter is not less than 5 inches and the pump 17 has a capacity for moving about 3,000 cu. ft. of air per minute. In the container 10 is a compartment 30 for the liquid, the container interior taking the sludge and solids, the flow of material being diverted into either from the pipe 38 by a flap valve 41 fixed to a spindle 42. The pump 17 is fixed to the vehicle chassis 12, the container 10 being pivotally mounted at 11 and having a bottom opening 48 communicating with the highpressure side of the pump 17. The liquid can be returned to the gulley 40 from the compartment 30 through an outlet 43 and a pipe 44 with a valve-controlled nozzle 45. On the lower end of the conduit 38 may be mounted a float operating means to indicate the distance of the conduit end from the level of the gulley contents. The compartment 30 may be a separate fixture to the chassis 12.