Coil punching machine combined with laser cutting: combined cutting systems with independent machines
Sometimes it seemed as though companies that wished to solve a problem related to productivity or efficiency had to put flexibility to one side.
The introduction of lasers solved this dilemma on coil-fed punching machines, introducing excellent levels of flexibility to a process that was already very efficient and increasing the productivity of the system, compared to mere coil-fed punching, and even more compared to sheet-fed punching.
For large volumes, companies that processed sheet metal using a sheet-fed system turned to embossing and roll forming lines to increase productivity, but complained that they had to endure a loss of flexibility for the time needed to change over the set of rollers.
Other times, companies that produced brackets and accessories from sheet metal would abandon sheets and turn to coil-fed embossing lines, which were very productive, but required a different die for each product.
The set-up times for product changeovers ended up reducing productivity for small batches.
Antonio Zambelli is the owner of FEMI-CZ SpA, a wonderful company based in Rovigo and a customer of ours for over twenty years, now part of a Joint Venture with a German group called Niedax. Founded in 1973, it began to grow in the 1980s, operating Dallan roll forming machines to produce profiles for cable systems and high-quality load-bearing structures.
This type of production also involves the production of a number of small sheet metal accessories and profiles with special holes are often required, given that the company is a leader in the supply of custom cable holder systems, based on specific customer requests.
Their production lines included perforating presses with progressive dies, but the technology of dedicated dies didn’t permit much flexibility.
They therefore decided to invest in one of our simultaneous Coil To Combo punching and laser cutting systems.
The system also includes a servo-electric parametric punching machine and (separated by a buffer or roller table) a laser cutting machine with vision system.
The solution, thanks to the integrated laser cutting vision system, made it possible to complete the cutting of pre-punched panels while the punching machine continued operating upstream.
As we’ve already seen, parametric coil-fed punching already takes place very quickly, eliminating the time required to trim pieces, as well as loading and unloading times.
The laser adds the same flexibility as a sheet system and, by performing laser cutting while the machine is operating, the line is always hugely more productive than any traditional system.
Together with FEMI-CZ, we added another element of flexibility: a certain number of products did not actually need laser cutting, meaning that the final module would remain unused.
Therefore, we added an unloading system between the punching machine and the laser, so that the punching machine and the laser might be used independently: the punching machine processes the coil and the products which are punched and cut to size are stacked immediately after the punching machine.
Loading individual metal sheets on the infeed roller conveyor means the laser cutting machine can be used at the same time.
Indeed, our laser cutting machine with vision system is still the only one that allows the use of both coil- and sheet-fed solutions!
Below is an account by Antonio Zambelli, CEO of FEMI-CZ:
“We’ve been working with Dallan, both the company and the family, for over twenty years and I’m certain we’ll carry on doing so and it will continue to be very rewarding. The time invested in launching the new combined CXN line is now producing great results for our company in terms of flexibility and savings under various aspects. FEMI-CZ is a company that, as well as an important quota of standard production, also has an equally significant quota of custom production, which has to be “invented” and organized each and every day, keeping under control both times and costs. The answer we found to both our standard and custom needs was this Dallan combined machine, which, having been conceived as “two machines in one”, further increases its use, thereby optimizing the investment.”
Using the link below, you can see the combined system with the independent modules in operation::
CASE STUDY – production of special pieces for shelving using a coil-fed punching and laser machine
The account provided by Günter Knecht, production manager of BITO Lagertechnik, is very interesting in that it explains the concepts of flexibility related to the Coil to Combo system.
“Bito Lagertechnik Bittmann GmbH is one of the European leaders in storage systems. Bito operates a highly innovative production program at its plants in Meisenheim and Lauterecken, with a surface area of 140,000 m2, focused on the customer and the highest levels of quality.
We process around 70,000 tons of steel sheets per year.
Production innovations are always triggered by specific market requests, such as the request for coil-fed punching and laser cutting.
In this case, our goal was to improve our ability to produce small batches, special pieces, prototypes and samples, to satisfy the great demand for flexibility and to produce special pieces based on specific customer requests.
The need for new products or products specially adapted to customer needs required flexibility in our production. Coordination with other departments is increasingly necessary when planning shelving systems. Automation, links to transport systems, lubrication systems, wiring and the integration of various storage systems require extensive optimization and continuous adjustments of the components related to the project. It was necessary to have the ability to align our production with these requirements, on every occasion.
However, we wanted to combine high flexibility with good productivity levels.
Hence, an important question arose time and again during investment planning: sheet-fed or coil-fed production?
In warehouse technology, components are over 3000 mm in length. Therefore, the production of special pieces is often a challenging when using a sheet-fed system.
Our experience shows that standard parts or project parts can be produced in large quantities from coils: that’s why it was worth researching and investing in innovative coil-fed production systems.
As production batches became smaller, precisely because of these special customer requests, there also came a need to produce these special pieces economically. To be successful, we had to be able to produce these small quantities economically and flexibly: it was a daily challenge for production managers.
There are some standard questions when planning special parts and small quantities:
- Coil-fed or sheet-fed production?
- Should we use expensive special dies, or should we move towards the complex production of unique pieces?
- How do we evaluate productivity, unit cost and production cycle economics?
Due to the sizes of the components often being over 3000 mm, coil-fed production is undoubtedly the most advantageous. Managing sheet metal in sizes over 3000 mm is much more difficult, expensive and the sheets often have very long delivery times and are unsuited to industrial planning. Furthermore, sheet-fed systems do not usually make optimal use of material: on the contrary, coil-fed systems always optimize the use of material, thanks to the width of the pre-cut coils.
On the other hand, we’re increasingly asked to produce prototypes for testing purposes, as well as having to produce pre-series pieces for static load tests before large projects get underway. It’s becoming increasingly preferable to produce pre-series samples long before planning investments on special dies that would be difficult to modify.
All the reasons set out above led to our decision to adopt flexible coil-fed production.
Before investing in the Dallan combined coil-fed punching-laser system, these pieces were made in different ways. Firstly, it was necessary to plan and agree the preparation of work and internal planning to check the availability of the necessary resources and tools.
The first option was to manufacture the components using temporary dies, on temporary or auxiliary work lines using a very complex multi-step process. For example, components were manufactured using already existing tools where possible, then we would take and manipulate the piece again to perform special punching, perforating or notching operations.
This caused significant problems with standard production:
- Extensive internal organizational effort
- High component costs
- Endless delivery times waiting for the delivery of test dies
- Tool costs that were out of control
- Extensive effort to continuously change and adapt components
- Excessive delivery and changeover times
The second option was to manufacture these special pieces using a sheet-fed punching machine. This solution can be adopted for one-off pieces or small quantities. Disadvantages often involve the quality of the edges cut or the necessary deburring of pieces; to get the same number of pieces, more raw materials were needed due to the amount of waste and production times were relatively long. The biggest problem facing BITO in this case was the limitation on the length of components: our punching machines are able to handle sheets up to a maximum size of 1500×3000 mm. Therefore, this production technology couldn’t be considered an alternative for components larger than 3000 mm.
Below are the production problems with sheet-fed punching and nibbling machines:
- Limitation of the size of components to a maximum length of 3000 mm
- Higher material costs due to a higher percentage of waste
- Complexity of logistics management and movement of all sheets and packs of sheets
- Need to deburr pieces
- Very high product unit costs
The third option was to purchase the products from the outside. The procurement of materials and delivery times were very often a major challenge with this option. Components could also be produced externally by larger machines, flat surface lasers or punching machines. In any event, sheets large enough for the length of the piece were necessary. The quality of the pieces also needed to be checked continuously, so we had to add the cost of internal and external quality checks. The cost of pieces was often a multiple of the cost of our standard components. In addition, there were high process costs for internal processes, when the designs of pieces had to be adapted and modified. Subsequent deliveries of missing components in downstream production processes posed another major problem with this alternative option.
Below are the problems with external production:
- Limited length – even for external production
- Length of components over 3000mm only using special machines and panels with special dimensions
- High costs
- Lengthy procurement times for sheets with particular mechanical characteristics according to specifications (yield strength, etc.). In general, the procurement of coils with special characteristics is easier and faster than that of sheets
- Coordination of production follow-up processes is often time-critical; for example, the time required for deburring internal edges or that of transporting external laser cut pieces for finishing requires an extensive organizational effort
- Tolerance coordination involving externally manufactured production pieces is complex
- Subsequent deliveries of missing pieces and pieces not within tolerance limits are not straightforward
So, we set the following goals for our new investment:
- Cost optimization in relation to current production and flexibility for the manufacture of special pieces
- Great flexibility for the production of special order pieces, with minimal investment in tools
- Increase of our productivity related to special pieces and small batches
- Reduce response times to make special pieces
- Reduce delivery times of said special pieces
- Use of coil-fed materials, which we already use for mass production
- Optimization of the production process
- Improvement of downstream processes, due to the ability to adapt pieces flexibly
- Production of samples directly in-house
- Production of samples before creating special dies and the ability to perform tests to optimize the figures of the special dies
- Optimization of the overall logistics of the process for special products and small batches
We also wanted to reduce the time to market of pieces produced to order and the manufacturing lead time of critical projects such as the production of prototypes, samples, products for load tests and static tests.
- Given that the costs for tools were low, indeed sometimes inexistent, it was possible to produce new products quickly and economically.
- Projects frequently involve single pieces.
- In research and development, there is often no precise data on the quantities to be produced and there is often the need for continuous and successive optimizations. Using traditional technology, this would have greatly increased the cost of prototypes.
When we need to make large quantities and standard components, we always use coils, special machines and tools. Usually. There are special presses and dies and downstream roll forming processes: we’re ready for this type of production and the procedure hasn’t changed, even after the introduction of DALLAN’s system.
Dallan’s solution allowed us to produce medium and small quantities, special components, unique components and even components over 3000mm in length. We could respond to specific customer needs with heightened flexibility and build prototypes and unique pieces and accessories, even for large projects. Dallan’s laser and punching machine gives us a combination of flexibility, provided by its punching and laser technology; in addition, we use coils and are therefore able to produce lengthy components to order without wasting material.
We usually have the coils required to produce special components for the production of standard pieces already in stock or we’re able to source them quickly. Therefore, we always have control over the quality of materials. Standard holes and notches can be made in the punching part using standard tools available on the market, which are cheap and quick to source.
Much of this flexibility is provided by the punching machine, which includes three arched tool drawers, containing 25 tools in all. The arches contain standard thick turret tools. They can be purchased from various suppliers (for example, from a company called PASS) and are available very quickly. The stations available range from 12 to about 150mm in diameter and four of the tools are rotating.
Larger tools can be used to insert standard tools with special shapes and multiple punching, up to a cutting power of 200kN. The tool holder arches can be moved along the numerical control transverse axis. By so doing, the tools are positioned automatically and quickly in the machine’s processing area.
The second part of the machine, the laser module, completes the special processing on pieces. The punching and laser combination provides extremely high flexibility and we combine it with very good productivity.
A huge advantage is the very short pre-processing time before starting production. Only a few hours pass from the drawing to producing the first piece that satisfies the specifications or from receiving a request to delivery of the first series.
An excellent example occurred during the installation of the machine: a number of pieces arrived damaged at one of our construction sites. We received a complaint because of this and, as usual, the replacement pieces would be manufactured by an external supplier and re-processed and folded by Bito. An initial check on the delivery times showed it would take 15 days from the order and involved: finding the material, external processing, cutting, sending it to Bito, folding operations at Bito and sending the pieces to the construction site.
We were able to verify out in the field how the flexibility of the new Dallan system could help us. After only an hour of processing the drawing in DXF using the programming software and installing the new coil in the machine, the first piece produced was already ready for our quality controls. After receiving the OK, we started production and the pieces were sent to the construction site the very same day.
The integrated packaging system downstream from the punching machine and the laser module also satisfy the need for flexibility and productivity.
Below are the advantages of coil-fed processing using the new Dallan system.
- Material optimization
- Good productivity levels
- Parallel production with the punching machine and the laser
- Very short production changeover times
- Continuous coil-fed processing (as opposed to stop-and-go sheet processing)
- Automatic loading and unloading
We still continue to use standard sheet-fed punching machines for processing small quantities. However, in light of the above, the quantities on those machines will decrease and the production of these pieces will also increasingly move to Dallan’s system. Good programming means it’s possible to produce very small series, even just a single piece!
During these initial months of project development and use of the system, we can relate the experiences we’ve gained out in the field.
In the project, the collaboration that took place during the configuration of the machines was excellent. Our requests were assessed and assimilated.
- Good teamwork between us and Dallan and good project management
- Excellent preparation of tests at Dallan
- Excellent management and organization throughout the project
- Good assembly and installation of the system at BITO. Dallan’s assembly and installation staff came across as extremely professionalism
- Good instructions and training
We will gladly continue working together!
Our experiences of the system so far:
- Our collaborators started working and understanding the system very quickly
- We have achieved the desired flexibility
- The objectives of cost reduction and the production of special pieces and small series have been achieved
- All internal processes for these types of production have been significantly improved. Thanks to the characteristics of the new system, the steps of the production processes are clearly defined
- We can completely eliminate the external procurement of special pieces: we can cover everything using internal technologies
- We have reduced the cost per piece, as expected
- In the coming months, we want to improve our ability to use the system and, more specifically, we aim to improve the following:
- Optimize the use of gas by optimizing cutting parameters
- Minor changes to the software by Dallan and Sigmanest
- Further training by Bito technicians”
CEO – Dallan Spa