Canmaking

Downgauging – the key to staying competitive

To contend with tough competition from PET, cardboard and other packaging materials, the canmaking industry is increasingly facing the need firstly to reduce production costs, and secondly to enhance the attractivity of cans.

Due to the fact that two thirds of the can costs are material costs, cost reduction has to be achieved mainly by reducing the material consumption:


  Downgauging of the tinplate for bodies and ends.

  Reducing the cut edge diameter of the ends by necking the can bodies.

  Further reducing the cut edge diameter of ends by using miniseams.

But make sure of required can resistance values!
(Axial load, panelling, buckle resistance, panel distension, pullback vacuum value)

Produced on Cantec canmaking machinery:

For tomato paste: Body thickness:  0.12 mm ( #43 ), end thickness:  0.14 / 0.15 mm ( #50 / #53 )
For petfood: Body thickness:  0.13 mm ( #45 ), end thickness:  0.16 mm ( #56 )

 Processes, can / end requirements and machine requirements
 for thin and low cost cans with high strength:

Process

Can / end requirement

Machine requirement

Die-necking

  high axial resistance:
  axial resistance is mainly
  determined by the necking angle

    steep neck angle smaller than 30 degrees
    neck re-forming by second necking operation
Beading   interdependence of axial and
  panelling resistance

  beading method:
    number of rotations and advanced bead depth forming
    bead geometries optimised by FEA calculation

Seaming
of DR ends

  adapted seam dimensions (SEFEL)
    mini-seam
    mini-flange
    mini-curl on the end

  seaming method:
    number of rotations and advance seam forming
    only minor fluctuation of flange dimensions
    swing-flanging

Production
of DR ends
    sufficient resistance thanks to
optimised geometry and
sufficient countersink depth

 
  precise curling (mini-curl)
  multi-die stamping press:
    rigid machine design,
    multi-stage or thermo compensating tool technology,
    FEA optimised panel design disc

curler: number of rotations

 

Press article:    From product idea to production line. ( pdf   )

 

From product idea to production line  
The permanent upward pressure on costs in the canmaking industry has resulted in a substantial reduction of development, engineering and project processing capacities. Where necessary, outside service providers are called in to make up for the lack of capacity. Due to their transition from classic mechanical engineering companies to system and service providers, machinery suppliers with their specific know-how play a particularly important part in this context.
Thanks to many years of know-how and experience with the planning and supply of complete lines, Cantec as supplier of turnkey system can offer support and cooperation in design, supply, commissioning and, last but not least, financing.
For many years Cantec has made a significant contribution - not only to the design and configuration of machines, but also to the development of the cans themselves by developing new cans and improving the stability or reducing the costs of conventional cans.

Product development
The demand for less expensive but also new and attractively shaped or recloseable cans is undiminished. Every order to develop a product and every cooperation in its development begins with the preparation of drafts in the form of photo-realistic 3-D images with calculations and, if necessary, FEA optimisation for a first presentation. Then individual sample cans are produced on test tools and machines to determine their forming potential and the process operations required. Next 100 to 200 cans are produced for a first laboratory analysis. At the last stage of development, 1,000 to 20,000 samples are produced for more detailed analysis, for canning tests or even for a local test market.

Product specification and line coordination
When the product to be manufactured (welded cans, deep-drawn cans, shells, ends or caps) has been determined, a detailed specification with definition of initial material and process operations isprepared. A line layout is then developed and discussed with the customer on the basis of this specification and the demands derived from it as regards sequence of process operations, line output, degree of automation, space available and integration of existing machinery. A homogeneous flow of material with as few deflections as possible, moderate conveying speeds and sufficient accumulation between the main units of the line is of particular importance for the design of the manufacturing line in order to achieve a high degree of efficiency. This is especially important for lines that run at high speeds or produce sensitive or difficult to form products. Ergonomic aspects are gaining in importance too. All production units should be easily accessible and quickly reached from a central location. In-line quality control and customer-specific PDM data for line control, monitoring and diagnosis must also be planned.

Interfaces
The lines supplied comprise machinery from Cantec (e.g. CAN-O-MAT, END-O-MAT, conveyors) and other manufacturers (e.g. welding bodymaker, palletiser, end packing, curing oven). Cantec has a wealth of experience with bought-out machines as regards their purchase, clarification of mechanical and electrical interfaces, testing and demonstration. It is our daily business to integrate and diverse machinery to form a homogeneous line.

Installation, commissioning and acceptance
The full service provided for a turnkey project also includes the organisation and execution of machinery installations at the customer's plant. Specialists for mechanic and electric tasks on site ensure that the new machinery and equipment, supplied by Cantec or by subsuppliers, is assembled and tested successfully and without loss of time. Once the acceptance test run has successfully been completed as stipulated in the contract, the line is handed over to the customer.

Training
Only complete and easy-to-understand operating and maintenance instructions and thorough operator training can guarantee that the customer will get maximum performance out of his machinery. Cantec organises theoretical and, above all, hands-on training at the manufacturer's plant as well as at the customer's site, and supplies comprehensive and well structured manuals for all machines.

Financing
Cantec not only organises the purely technical and logistic handling of a turnkey project, but can also be of assistance with financial matters - by personal discussions and together with the financing experts of all major banks worldwide.

Accessories and operating material
Apart from the supply of turnkey manufacturing lines, Cantec also plans and supplies accessory equipment such as laboratory equipment to measure can bodies and ends or workshop equipment for smaller repairs. Our range of supply also includes operating material, for example pallets, skeleton boxes, fork lifts, consumables and raw materials such as tinplate, copper wire, lacquer and paint.

After sales service
The customer is not left alone even after the line has been handed over. Cantec's service department is at his disposal day and night and provides the fastest possible assistance wherever required - by fast data transfer by Internet, control, updating and modification of controlling data and remote diagnosis. The fastest possible supply of original spares and preventive maintenance on the basis of maintenance contracts are the equivalent of a life insurance policy for manufacturing lines.

Cantec – THE partner for an all-round service package.