GB1472599A - Heat-exchanger with cleaning means - Google Patents

Abstract

1472599 Cleaning heat exchangers H WIEDERHOLD 23 April 1974 [25 April 1973] 17640/74 Heading F2N A heat exchanger incorporating an internal cleaning arrangement that may be used while the exchanger is operative comprises an array of pipes 2 and a drive (not shown) to move closefitting hollow cylindrical scrapers 8, whose length excedes their maximum transverse dimension, along the pipes when they are to be cleaned. The pipes 2 are held by plates 3 and 3<SP>1</SP> with their ends open to spaces 5 and 6. Steam flows into and out of the space 4 between the plates via pipes (not shown) to heat a fluid, e.g. a paint solvent which itself flows into space 5, through the pipes 2 and out via a pipe 7. The drive is a pneumatically-operated piston and cylinder arrangement whose motion is transferred simultaneously to each of the scrapers 8 by the rods 12 and 9 and the plate 10; the travel is sufficient to cover the entire length of the pipes. The scrapers are in the form of hollow cylinders 8a connected by struts 8b to the rods 9, the cross-sectional area of a scraper being less than that of the associated pipe. In an alternative arrangement (Fig. 3, not shown) three scrapers are fitted to each rod 9 so that the travel may be reduced to <SP>1</SP>/ 3 of the pipelength. Another design of scraper (Fig. 4b, not shown) consists of a cylinder with a number of holes bored longitudinally through it. Hydraulic or mechanical drives may be used.