GB745583A - Improvements in or relating to containers for powdered materials - Google Patents

Abstract

745,583. Pneumatic conveyers. AMALGAMATED ROADSTONE CORPORATION, Ltd. Dec. 16, 1954 [Sept. 22, 1953], No. 26117/53. Class 78 (1). In means for discharging powdered materials e.g. cement, limestone and coal dust, from containers of the kind in which discharge is effected by admitting gas under pressure into the container to fluidize the material and is assisted by admitting pressure gas directly into the discharge pipe, the admission of gas into the discharge pipe is controlled by a valve which opens automatically when the pressure in the container reaches a predetermined value and closes when this pressure falls. The conical lower part 13, Fig. 1, of the container is made in two parts, the lower of which, 13<SP>1</SP>, has spaced walls 16, 17. The outer wall is of metal and the inner one of porous material, e.g. canvas, sponge rubber, latex foam or hair. The inner wall may be mounted between perforated metal plates. The upper part of the wall 17 is perforated and is encircled by a plate 18 of L-shaped crosssection. Gas is admitted to the chamber 19 formed by the plates 17, 18 through the branch 24 of a supply line 25. This line is connected also by readily detachable means to a pipe 21 disposed in the flared end of the discharge pipe 22. The flow of gas through the pipe 21 is controlled by a valve member 26, Fig. 2, carried by a stem 27 which is attached to a piston 29 working in the casing 21<SP>1</SP>. An extension of the stem below the plunger engages an abutment 30 for the upper end of a coiled spring 31. The lower end of the spring bears on an abutment 33 which can be moved by a screw 34. This screw is turned to vary the compression of the spring and hence the pressure keeping the valve member 26 on its seat 28. A conical skirt 23 mounted on the pipe 22 deflects falling material against the wall 16 to ensure a uniform flow into the pipe 22.