When it comes to bending sheet metal to precise angles and dimensions, there is no better suited machine than the press brake. As one of the many principle pieces of equipment in the metal industry, the press brake helps deliver custom parts to a range of industries including aviation, automotive, agricultural, energy and transportation.
Press brakes abound. Virtually every fabricator has one, and many underutilise them or operate them inefficiently. Bending technology has advanced to promote quality improvements, but press brakes still remain one of the most labour-intensive machine tools.
In the face of global competition, fabricators are looking for new ways to lower per-piece costs. So what about automation? Robot automation can be an attractive option because of the well-known efficiency improvements realised in other metalworking and industrial applications where robots replaced manual operations. Conventionally, most press brakes are operated via programmable system inputs and cut-to-size blanks are still aligned and placed manually before bending.
From small parts to large, unwieldy sheets of metal robots are ideal for press tending applications. By utilising various gripper options and flexible regrip/orientation stations, difficult positioning is easily achievable during the bending sequence. Various parts are accommodated with an automatic tool change unit which allows the robot to select the correct gripper for the work piece. Depending on requirements, infeed magazines, outfeed pallets, conveyors and other peripherals can be fully integrated for a complete automated press brake solution.
Specialist machinery supplier Metal Chip Machinery and the South African operation of Yaskawa collaborated when a client manufacturing DB boards, electronic enclosures and boxes approached them to provide a solution for his business. Robot press brake tending is not new to South Africa and there are some local examples. However, the uptake has been slow even though there are enormous benefits that can be achieved.
The robot and press brake integration was first established between Coastone, the Finnish press brake manufacturer and represented locally by Metal Chip Machinery, and Yaskawa Finland five years ago.
“When we had an enquiry for a press brake bending and robot setup, it was a natural progression for us to talk to each other. There is an existing interface between the Coastone press brake and the Yaskawa robot, which made offering a local integration solution a lot easier,” said Malcom Moriarty of Metal Chip Machinery.
“The opportunity to supply a customer in South Africa with a robot tending press brake solution arose when an existing client requested a solution to speed up their manufacturing process. The task was to create a solution for the company that uses press brakes to manufacture his electrical boxes that are designed for domestic, factory and industrial use,” he explained.
“The reason we approached Yaskawa was because of the existing relationship in Finland. The customer wanted to move away manual process to one of automation with a robot so as to achieve higher volumes of production.”
Automation is synonymous with providing cost-effective solutions to customers and the press brake integrated with a robot aims to do just that. The opportunity for local fabricators to rise above international competition is to automate.
“The majority of electrical boxes that are sold in South Africa are very often produced in countries like China, so to remain price competitive, the cost per unit has to be reduced.”
For all the benefits that robots and automation bring to the table, the most common follow up questions tend to be about maintenance. When it comes to maintenance, very little is needed on the robot for at least the first seven to eight years, other than just the standard services, robot manufacturers say.
On the press brake side, Moriarty has experienced machines in perfect working order that have outlived his entire career so far and says that newer technologies are “essentially maintenance free as these are fully electric press brakes that use no hydraulic oils, eliminating the need for filter changes. They are operator friendly and easy to use.”
“Robots and press brakes may offer higher productivity and better profitability, much of which is achieved by running the press brake lights-out at top speed. In some cases, a robot and press brake combination can reduce per-piece costs by almost half. Still a robot and press brake combination is not for every application. With constant pressure to extract time and money from every process, many companies have few resources available to research all possibilities. They tend to focus on the attractive per-piece cost without exploring other creative solutions.”
“What has changed dramatically over time is that the software and controls. The design of the structure of a press brake has also improved dramatically.”
Moriarty notes that the Yaskawa robot integrated press brake will be this client’s second press brake, building on their operational efficiency even further following their initial investment. “The first one already doubled their production in manual mode.”
“The robot is fitted with a vacuum gripper device with suction cups that pick up the various blanks of sheet metal and presents them to the press brake for bending. The gripper is designed to easily handle the material despite the blank’s change in shape.”
Before product delivery, Yaskawa provides all customers with training for the robot operators. This is followed by a collaborative process whereby both the press brake and robot are programmed and calibrated to suite the application.
For more information contact Metal Chip Machinery on TEL: 011 476 7509 or 072 834 3164 or visit www.metalchipmachinery.co.za