TPT May 2017

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AR T I C L E
Rivit SpA
MAY 2017 81
In order to evaluate the production potentials of HFree electro
pickling it has been compared with the traditional chemical
pickling process, which allows the treatment of one or more
tubes simultaneously during the same dive cycle according
to its size.
The production has been standardised based on the
geometrical characteristics of the material that is being
treated and this has helped to obtain an average pickling
time for tubes and for the more critical alloys. The results are
summarised in Figure 3.
As can be seen, the ‘HFree’ process for a single tube
appears to be very convenient in its treatment of large
diameters. The condition becomes critical with smaller
diameters where the traditional process allows the treatment
of bundles of tubes.
For this reason the second stage of the research has been
directed towards the analysis of the number of tubes that can
be treated in the minimum cycle in the range of diameters
shorter than 365mm.
Figure 4 shows the time for small diameter tubes, assuming
to treat tubes per cycle.
To obtain the diagram shown in Figure 4, certain perfor-
mances have been assumed in the industrialised process that
decrease with the increasing number of tubes per cycle.
In conclusion, HFree Life Pickling has developed an eco-
industrial process that entailed remarkable environmental
benefits with the complete elimination of the toxic substances
and the consequent reduction of the environmental impact.
Moreover, the process has achieved excellent production
capacities, with possible potential for improvement connected
to the chosen plant engineering and a containment of
the costs correlated to less energy used compared to the
traditional process with consequent benefit, even from an
environmental viewpoint.
Rivit SpA
36030 Caltrano, via Andrea Palladio 129, Vicenza, Italy
Fax: +39 0445 359 300
Email:
Website:
0-365 365-699 700-800 800-1016 Ø>1016 [mm]
8
7
6
5
4
3
2
1
0
1 2 3 4 5
0,8
0,7
0,6
0,5
0,4
0,3
0,2
0,1
0,0
nel [N° tubes per cycle]
tt “HFree”
tt “HFree”
tt “1300R”
tt “1300R”
Pickling time for one tube
Pickling time for one tube, small diameters
Figure 3: Time for one tube in the two processes
Pickling time for one tube [h/tube]
Pickling time for one tube [h/tube]
Figure 4: Time for tube of the two processes in small diameters,
Ø<365mm