FOCUS ON ROLL BENDING
Examples of products manufactured by RIETHO GmbH Stanz & Biegetechnik .
Its recipe for success also lies in the roll geometry or , more precisely , in the type of crowning developed by Schröder-Fasti
Founded in 1986 , RIEHTO GmbH produces high-precision parts in any quantity . RIETHO ’ s customers appreciate flexibility . The supplier can offer a wide range of production capacities , with corresponding machinery , and has 150 employees . When it comes to high-quality , attractive sheet-metal housings , roundings are always in demand .
The DIN EN ISO 9001:2015-certified company makes no compromises when it comes to precise slip bending . Following its experience with three folding machines and a guillotine shear from Fasti , the electronically controlled slip bending roll Type 134 from Schröder-Fasti was purchased to fill a gap in RIETHO ’ s capabilities to provide sheet metal with precise radii of any size .
Quality is machinedependent
There are many suppliers of slip bending rolls in the market , but RIETHO always chooses Schröder-Fasti for its spindle drives
( without follow-up
The SPS CR80 control . movement ) and solid , torsion-free machine bodies . Its recipe for success also lies in the roll geometry or , more precisely , in the type of crowning developed by Schröder-Fasti .
“ As with crowning of the folding beam in a folding machine , crowning of the rolls helps to achieve even bending results thanks to the bending forces . Slip bending rolls are each specified for certain sheet thicknesses and radii because , if the crowning is incorrect , the sheet edges of a round bent sheet will diverge concavely ( if the crowning is too small ) or convexly ( if the crowning is too large ),” explained Schröder-Fasti .
One consequence of this is , for example , that an uneven tube cannot be welded cleanly . Slip bending rolls are therefore each suitable for a certain range of tasks . Schröder-Fasti clarifies this with its performance diagram , which shows which sheet thicknesses and folding lengths at which tensile strength values can reap high-quality results from a machine .
“ In practice , users sometimes deviate from these specifications , depending upon the quality requirements of the workpiece , but ultimately the following applies …. only with the right machine can you achieve the requested radii in your sheet-metal parts ,” explained Schröder-
Fasti .
Two machines in one
RIETHO had been using a Fasti 125-10 / 1.0 with a 50mm top roll , a 136-25 / 2.5 with a 140mm top roll and another Schröder-Fasti slip bending roll with a working length of 1500mm and a roll diameter of 160mm for some time . The prospect of new orders and the need for a machine in the medium-performance range led the manufacturing service provider to order a slip bending roll Type 134-15 / 2 with a working length of 1500mm for 2mm thick sheets .
RIETHO normally processes steel sheets from 1-3mm in thickness . To ensure that already punched sheet metal and 1300N / mm ² sheets for food technology products do not damage the rolls , the option of hardened polished rolls was chosen . Another equipment option was the change gearbox which enables the top roll to be exchanged .
While the order was still being processed
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