METAL CANS PRODUCTION

3 PIECES - 2 PIECES COMPARISON

As everybody knows, the production of metal cans occurs for the most part by means of central body welding (realized with rectangular bands properly rolled up) on which the bottom and lid are seamed.
So this technology of production is defined 3 pieces technology.
During the last decades a second technology, that at the beginning was dedicated only to those pieces having a very reduced height, is developing. It's the 2 pieces technology.
At the beginning the need to increase this second technology was felt for ecological reasons seeing in the can body welding a danger for the public health.
So the welding machines manufacturers were awakened to study alternative materials for welding able to make such operation the most innocuous possible.
So it occurred substantial modifications and the situation is decidedly more correct than during the past.
In the meanwhile many manufacturers of cans taught and realized, as alternative, the 2 pieces technology having no ecological contraindication.
So the drawing technology, that till that moment, perhaps for instinctive laziness, was not sufficiently engaged to express its best for small thickness and pre-painted material too, was more involved.
So from year to year the absolute dominion of the 3 pieces started flexing pro the 2 pieces technology. This also because the technology of iron metallurgy, of chemistry for paints, of lithographic machines took a step forward putting at drawing disposal more flexible elements proper to this very exacting operation for the resistance of the material to be employed.
Naturally, as natural way of every development, as successes of rendering and of adaptability to drawing operation were obtained, the other aspects too, that could be defined positive, were considered.
So it was put the attention and the valuation also on the external aspect of the 2 pieces that was decidedly more appreciable than that of the 3 pieces and the direct and indirect possible advantages obtained by a safety of liquids seal were considered.
So we have outlined a range of positive differences with regards to the 2 pieces that can be resumed in Ecology - External Aspect - Inexistence of leaks.

Naturally the 3 pieces technology keeps a basilar prerogative represented by the highest speed of production per hour with regards to what it can be obtained by the 2 pieces technology.
In this case and only in this case it's based always today the big difference, even if a little bit reduced, between the quantity of the 3 pieces cans and the 2 pieces cans.
However, as it happens during every logic comparison between different parameters, it exists a relation between the quantity potentially producible and that really necessary.
Practically this means that the can manufacturers, who need and for whom it's sufficient a lower number of producible pieces, can be interested in compare which is, among the different alternatives of parameters available, the best solution for him representing the best relation between utility of production and cost of investment.
For this examination, that especially for little and medium manufacturers is daily necessary and useful, the packaging industry finds a help in the technicians and in the experience of BMV which Partners-Technicians since 40 years have dedicated their activity to the automatic sheet plate pressing studying and realizing complete systems for a vast range of industrial sectors.
BMV has decided in 1997 to dedicate its double experience, both at tools and presses level, with an higher specific devotion, to the metal packaging industry.
So it started to examine what it had been already made in the automation of production of drawn pieces and it has been able to point out that its technique and its flexibility, due both to its long experience and to its family management, would have represented for the interested Customers an important and sure reference in the comparison research and in the choice of 2 pieces or 3 pieces systems.
Even being always disposed to accept easy further alternatives for eventual more particular cases, BMV has launched a range of 8 different models of complete systems for the production of 2 pieces metal cans.
BMV is now making a slow but continuous action of information towards the probable world-wide Clientele looking for the major part of possible contacts for a constructive dialogue and to establish together with the final end users which can be the favourable fields of 2 pieces and those of the 3 pieces.
This is made trying to put the maximum experience at their disposal, experience that, just because real, shows which are the limits of production that we can guarantee.
So BMV doesn't intend to publicize the 2 pieces systems in senseless and speculative way, but, on the contrary, it wants to put the probable Clientele in condition to make a valid and reliable economic comparison, exclusively leaving at the end user the comment concerning the results of such comparison on the basis of logic mathematical considerations.
To be able to offer to the eventual Customers the valuation of its alternatives, BMV asks at each applicant to point out:

- diameter + height + thickness of each piece - total quantity per year of each piece - quantity of pieces per minute desired - choice of shifts per days foreseen

After having submitted to the applicants' attention its proposals, BMV is glad if it can be informed about the comments concerning the results of the comparison, preferably on the occasion of a meeting during which we can examine together the elaborated parameters.
Through the studies realized till now, it results clear a net advantage in many cases of the 2 pieces for cans with height till 69 mm. at the presence of a quite high quantity per year too.
A practical examination of these studies is at disposal of those who are really and directly interested in these comparisons.
BMV, studying the vast range of Transfer Presses that it will employ in the most flexible realization of complete systems for the 2 pieces cans, has also examined the possibility that such transfer presses can be eventually employed for the 3 pieces cans too, i.e. Rings - Lids - Bottoms to allow the end user to obtain the maximum exploitation of the complete system.
During the dialogue between BMV technicians and the Customers concerning the choice of the more suitable system for each one of them, it raises a series of possibilities that surely will satisfy a big number of end users.
Here after we show in summary a range of standard systems foreseen by BMV.
As we can point out, each one of the 8 different dimensions ranges has several alternatives on the basis of the quantity per year we want to produce.
The quantity of pieces per year shown in the schedule is that effectively obtainable and so not theoretic.
The number of pieces refers to 2000 working hours per year that generally refers to a working daily shift and it's clear that doubling the shift the production doubles.
BMV is pleased to remain at Your complete disposal for the examination of every Your need that it will be studied with the maximum spirit of collaboration.

T4 50 8

T4 100

Complete System