ISMR November 2023 | Page 33

FOCUS ON PUNCHING

On the Boschert MP 4020 , Hungerbühler can process sheets of up to 6000mm in length using the repositioning process .
A customised solution
The St . Gallen company specialises in large pieces of up to six metres . However , it still lacked the right punch press . A smaller system was in use which brought challenges such as a lot of transfer work at the table and the associated risk of misalignment . A better solution had to be found so HMH Hungerbühler GmbH decided to look for a punching machine on which it could also process sheets in XXL or super format quickly , easily and economically .
“ We had a 6m shear , a 6m laser and 6m press brakes ,” outlined Markus Hungerbühler . “ What we still needed was a corresponding punching machine that could do ‘ that certain something ’ more than any other .”
However , he was unsuccessful in his market-wide search . Even his longstanding sheet-metal technology partner , Boschert GmbH & Co KG in Lörrach ( Germany ), did not have a suitable machine in its portfolio at the time .
“ It took another two years until the penny dropped and I sat down with Boschert again to discuss a large punching machine ,” remembered Hungerbühler .
The partners came up with a solution : a development order for a punch machine for super-format sheet metal .
“ It was a real win-win deal . Thanks to our cooperation with HMH Hungerbühler , we had the scope to design this machine from the ground up ,” explained Michael Roser , Sales Manager , Boschert . “ Markus Hungerbühler was significantly involved in the development and was able to contribute his ideas and wishes . The specifications with the features that we would have wanted were three pages long .”
Boschert implemented a reported 95 percent of these specifications into the MP- 4020 when it celebrated its premiere a year and a half later at the Blechexpo 2019 exhibition in Stuttgart , Germany .
Supersized sheet punching
The heart of the Boschert MP 4020 is its robust O-frame . This stabilises the machine like the closed frames of a submarine .
“ This means that operators can use the 28 tons of the MP 4020 ’ s punching force quickly and with repeat accuracy . The machine can punch , nibble , form or mark sheets of up to 6mm in thickness . The 12-station tool changer significantly reduces non-productive times ,” said Boschert .
“ The MP 4020 is equipped with two punching heads . The upper punching head with 55mm punching stroke is equipped with HDE hydraulics for rapid stroke and
Small components of up to 400 x 2000mm are automatically removed via a flap in the machine table .
accurate punching . The punching head can be continuously rotated through 360 degrees and can hold all TRUMPF standard tools up to size three ( Ø105mm ). The machine also has an active die with an automatic alignment function for punching from below . The lower punching head with 25mm punching stroke is equipped like the upper one . The maximum stroke rate of the MP 4020 is 800 strokes per minute ,” it continued .
The machine can be used to process panels from 100 x 280mm up to super format 4000 x 2000mm . Loading is easy : the machine table is accessible and features practical helping aids . These include a special opening in the table that makes it easier to insert sheets , as well as liftable ball rollers that support the user when placing super-format sheets .
The panels are clamped with up to four pneumatic clamps and moved in the ‘ x ’ direction by a servodriven precision rack and pinion drive . This adjustment allows users to process sheets over 4000mm long . Another servo drive moves the punching heads synchronously at the top and bottom in the ‘ y ’ direction . Positioning speeds of 75m per minute on the ‘ x ’ and ‘ y ’ axes are possible ; simultaneously up to 106m per minute speeds are also possible .
The CNC punching machine has a disposal flap through which scrap metal parts ( measuring up to 400 x 2000mm ) are transported by conveyor belt either to the operator or to the left end of the table . The ‘ y ’ axis boasts a travelling punching slug extraction , and any punching waste is transported to the collection container via a conveyor belt . The scrap skeleton can be unloaded behind the punching unit .
With the MP 4020 , Hungerbühler produces newly developed lightweight safety components for mobile homes in one clamping operation and with one automatic tool change . The 200 shapes are punched from above , and the system then sets up the high forming shapes from below .
ISMR November 2023 | ismr . net | 33