Special Heat Exchanger tube bundle extractor

the extraction of the tube bundles was possible thanks to the use of an extractor designed and built by the VED of Priolo Gargallo

On two vertical axis heat exchangers

The tube bundles had not been extracted for a long time and since the exercise revealed thermo-fluid-dynamic anomalies, their maintenance was decided. Previous experience and the careful assessments of the refinery technicians were crucial to hypothesize that the extraction of the tube bundles of these exchangers might require special equipment. Formation of solid product between the fixing holes of the tube plate to the shell and the threaded rods, as well as other product which wrapping the tube bundle, more markedly in the area next to the tube plate, packed it with the shell, prevented the extraction and so that this happened it was necessary to apply an extraction force of 650 tons. It was not enough to simply apply this force, but it was necessary to manage it intelligently, to counteract the jamming phenomena and break the bonds between the tube bundle and the shell that are practically glued. While for the extraction of one of them it was sufficient to apply the special equipment only initially for a stroke of about 400 mm, and then extract it completely with a crane, for the other it was necessary the special equipment for an initial stroke of almost three meters and this because the tube bundle was very dirty and the tubes and diaphragms exhibited excessive deformations and crawled against the mantle.

An extraction force of 650 tons had to be applied.

Eight 1 1/4 ”extraction holes were made on the tube plate, in addition to the four existing ones. The same number of threaded rods with a length of 2,400 mm were inserted into the holes and the force was exerted by twelve hydraulic cylinders with a through hole; each cylinder was capable of exerting a force of 60 tons at a pressure of 700 bar

 

 

 
 
 
Characteristics of the exchanger:
  • Dimensions: 1,040 / 8,000
  • U-tube quantity: 525
  • Exchange surface: 496 m2
  • THEME type: DEU
  • Shell Side Fluid: Feed + Gas
  • Pipe Side Fluid: HDS Effluent
  • Jacket temp., In / out: 235/370 [° C]
  • Temp. Tubes, in / out: 395/320 [° C]
  • Jacket / Pipes Pressure: 186/169 [bar]
  • Exchanger Weight: 60.000 [Kg]
  • Tube bundle weight: 8.000 [Kg]
 
 
 
 
 
 
 
 
 
 
author: Ing. Armando Falla

Leave a Reply

Enter your keyword