Bending automation has changed from yesterday’s costly, customized systems designed primarily for long production runs to new standard-configuration bending cells that are fast and easy to program, require no robot teaching and deliver a low cost per part for small batch sizes. A growing array of robotic bending cells, several showcased at Fabtech, range from compact and budget-friendly to fully autonomous. For those fab shops under pressure to bend a variety of parts in smaller quantities with shorter lead times and at a lower cost, bending automation may be the solution. Before making the leap to automation, however, you should consider three fundamental questions.
Why do I want to automate?
There are many business challenges driving automation – a shortage of skilled labor, need for higher quality, less manual handling, more ergonomic work environment, improved process flow and lights-out manufacturing. It’s incredibly basic, but it’s critical to be clear on why you want to automate. Many fabricators lack the skilled operators to handle the workload and suffer from production operations with unpredictable material flows and quality control issues.
Automation seems logical as it addresses the need for operator labor and introduces consistency to the manufacturing process. But there is no one-size-fits-all bending cell capable of handling every bending job.
If you don’t define your automation goals, you risk over-automating. Over-automating is a common mistake that results in an increased cost per part and a higher cost for the cell, making it practical only for higher production volumes. OEMs are more susceptible to this risk because they have longer production runs for the parts or products they produce.
However, even OEMs are experiencing smaller part and product volumes because of minimum stock requirements and just-in-time manufacturing. Also, keep in mind that as product life cycles become shorter, a cell dedicated to production of a specific part requires significant modification to be repurposed for a new product.
The right bending cell measures your automation goals against your production reality. If the fab shop typically produces brackets no larger than 600 mm by 400 mm (23.6 in. by 15.7 in.) and weighing less than 9 lbs., a compact, cost-efficient cell may be ideal. The LVD D-Cell is priced under $225,000, uses a simple hydraulic press brake without a measuring device and requires manual tool change. For a more autonomous system to bend a wider range of parts up to 1,200 mm by 800 mm (47 in. by 32 in.) and weighing as much as 55 lbs., LVD offers the Ulti-Form system, a bending cell built around an automatic tool changer press brake.
What should I automate?
As with investment in any type of fabrication equipment, application and volume are key. Identify and prioritize which components will benefit from automated bending and what production level will be needed. Focus on your most frequently produced parts, evaluate minimum and maximum part sizes, material thicknesses, part weights and forms. Allow for your largest, heaviest and thickest part as well as typical quantities and year batch sizes. A large-quantity, repeat job is no longer the perfect or the only application for robotic bending. Modern bending cells come in standard configurations that make small batches cost-efficient to automate.
To choose the system that is right for your needs, evaluate your current part mix and consider any future development of that mix. This may be a challenge for subcontractors that don’t know what parts they will produce tomorrow, but even so, planning for the “what ifs” will help you make a more educated investment that returns a more favorable outcome.
Bending cell facts
- The new generation of bending cells are quick and easy to program offline and require no robot teaching. This makes them more suitable for varied day-to-day production demands.
- The modern bending cell uses offline programming to reduce setup times (programming and part setup in 5 to 30 min., depending on part complexity). This makes automation economical for smaller batches and lower part quantities.
- There are many different solutions. Evaluate the applications (part sizes, weights, volume) to define the cell best for the fab shop.
- Robots are limited in payload (maximum weight for gripper and part) and inertia (maximum part size). Large robots are slower than small robots.
- Robot bending is not always faster than manual bending, but offers higher reliability and consistency.
- Cycle time is more than just bending, it’s also material flow.
- Automation has a cost; the more that is automated, the higher the cost per part. Don’t over-automate. For the best ROI, strike the right balance between automation and cost per part.
- Robots support operators in production; they do not replace them. A single operator can manage multiple bending cells.
What is my budget?
A dedicated bending cell – the traditional, long-production-run system engineered for a specific application – is typically three to four times the cost of a press brake. New bending cells designed in standard configurations that can handle a diversity of parts and batch sizes are less than twice the cost of a press brake, making them much more affordable for fab shops.
For these systems, the features and functionality required to produce the parts you want to automate dictate the cost of the bending cell. A lower cost bending cell incorporates fewer features and a more basic press brake. A fully automated cell uses automatic tool changing and offers the repeatability of adaptive forming and CNC crowning, as well as increased input and output capacity. A bending cell using a 6-axis backgauge provides the flexibility to handle more complex shapes, but also comes with a higher price tag. However, even the most full-featured of standard bending cells can be surprisingly affordable.
Do the work to define the applications you want to automate to help set a price point for your bending cell investment. Defining the parts you want to automate will help determine the ideal tonnage of press brake and setup for tooling and robot. Consider a bending cell capable of both automated and manual operation. This provides more for your investment as you process large lots automatically and bend small lots, individual parts or especially complex parts manually on the press brake.