GB618150A - Improvements relating to heat exchange apparatus - Google Patents

Abstract

618,150. Tubular heat-exchange elements. PORTEOUS, W. K. Oct. 26, 1946. No. 31825. [Class 64(iii)] [Also in Group XXVIII] A heat exchanger suitable for carrying sludge or other liquids having solid particles in suspension comprises units of concentric tubes arranged with their axes substantially vertical. The outer tubes 1 of each unit are flanged and the annular spaces between the concentric tubes in adjacent units are interconnected through a onepiece H-shaped hollow member 5 which abuts against the outer tube flanges 2. The inner tubes 3 extend beyond the outer tubes and pass through the parallel arms of the H-shaped members 5 and are connected together by hollow U- shaped members 7 and are provided at one end with a flange 4 which is held between the flanges 6 and 8 of an H-shaped member and a U-shaped member respectively, the other end of each tube being surrounded by a gland 10 in a stuffing box 9, the flange of the latter being held between two flanges 6 and 8 in a similar way to the flanges of the inner tubes 3. In order to allow free expansion of the inner tube through the gland 9, the U-shaped member associated with the stuffing box has a short recessed portion, the diameter of the recess being the same as the external diameter of the inner tube 3. At the end where the fluid enters, the inner tubes are provided with replaceable steel liners 11 each having a flange 12 which rests upon the top rim of the tube. Hard removable sleeves 13 and 14 fill the ends of the annular space between the tubes and are tapered off towards the centre-line of the H-shaped member and the top sleeves 13 have flanges 15 which seat in recesses 16 in the upper H-shaped members and the bottom sleeves rest on the flanges 4 of the inner tubes 3. A heat-exchanger comprises a series of such concentric units supported in a girder framework, the units being arranged in lines and the end unit of each line being provided at the top and bottom with T- shaped castings replacing the H-shaped castings on the other units, further U- shaped castings being used to connect the units of one line with those of an adjacent line. The heat exchanger is enclosed in a lagged casing with a detachable sectional roof of corrugated iron and hot flue gases from an external source are circulated in the casing in the spaces between the concentric tube units. Baffles are provided to cause the flue gases to take a tortuous path, the top set of baffles serving as a platform for carrying out maintenance work.