C 32 U | RS 2 robot system | BWB-Betschart | Specialist in surface coating
BWB-Betschart is a specialist in surface coating. The Swiss company entered the machining business in response to demand for aluminium components for furniture construction. Today, the furniture industry hardly plays a role – instead BWB often acts as emergency support for its surface-coating customers. A new 5-axis machining centre from Hermle, automated with an RS 2 robot system, ensures adequate flexibility and capacity.
"The Hermle machine floated in through this hatch in May 2020." Thomas Furger, Head of CNC Machining at BWB-Betschart AG, points to the opposite wall of a bright, low-looking hall. In addition to heavy load racks, roller carts and pallets with blanks and finished parts, there are several machine tools here – and they make a lot of noise. "The opening through which we manoeuvred in the equipment with a crane is only a few centimetres higher than the stainless steel cover of the tool spindle. We also reinforced the floor – for safety," describes Furger. The millimetre-precision work and the time and effort involved in the run-up were required because the machining department is located on the second floor. "It's been that way historically," adds Furger.
It all began in 1963 with an anodising plant of BWB Oberflächentechnik in the canton of Nidwalden, south of Lake Lucerne. Today, the parent company, BWB-Holding AG, operates twelve production sites in Switzerland, Germany, Romania and the Netherlands. The Swiss company specialises in electrolytic, chemical and galvanic surface coatings for applications in aviation, industry, medical technology and architecture.
Only the subsidiary BWB-Betschart offers machining of aluminium as an additional service at its headquarters in Stans-Oberdorf. "Our core competence is coating. Machining was added later at the request of our customers. About 20 years ago, for example, we received an enquiry from the furniture industry asking whether we could also take on the machining of aluminium furniture legs in addition to surface coating," says Furger. BWB-Betschart agreed and initially outsourced the work. Four years later, the company decided to set up its own profile machining centre. "These are the machines which were so loud," says Furger. Ten years ago, BWB went one step further and invested in its first 5-axis CNC machine for milling workpieces up to three metres long.
The decline in sales in the Swiss furniture industry brought upheaval: Instead of furniture manufacturers, BWB was approached by surface customers who had capacity bottlenecks in their own machining. "To this day, about 90 to 95 per cent of our clients do their own milling in their machining departments," explains Furger. "We are often the front runner and troubleshooter – specialising in aluminium."
Over time, the order workload in CNC machining outgrew the personnel capacity. "We had to work two to three shifts and use workers from other areas. However, for smaller quantities or new orders, we eventually ran out of qualified employees," explains Furger. The remedy was to be an automated 5-axis machining centre. After two years of planning, a special crane finally hoisted in a C 32 U from Maschinenfabrik Berthold Hermle AG, including the RS 2 robot system for automatic pallet and workpiece handling. A special feature of the equipment from Gosheim is the vacuum clamping system which BWB-Betschart ordered in addition to the hydraulic clamp – especially for its customers from the aviation industry. As their components are weight-optimised to the maximum, they are designed to be particularly filigree and thin-walled. "The danger of the vice deforming the parts during the first or at the latest the second clamping was too much for us here," explains Furger.
In addition to the intuitive control, reliability and high precision of the Hermle machine, the decisive factor was the uniform coordination of the overall solution. "We had also looked at other concepts. "However, we lacked the experience in automation to bring two independent companies together and explain to both what we needed," says Furger. "Here we have everything from one source. If something doesn't work, Hermle comes and solves the problem". Hermle lives by the concept of 'one contact person' even during the project phase, something which Furger appreciates very much: "We were assigned a project manager who was absolutely up to the job and always committed. If a question initially remained unanswered, we would receive feedback within a day or even a possible solution."
The C 32 U has been in operation since summer 2020 – the first six months rather at a "very low level", as the head of CNC machining reveals. From January 2021, utilisation jumped to over 90 per cent. "Without this machine, we would have had to cancel well over half of the orders at that time. In addition, we required high precision for some parts," emphasises Furger and reports on workpieces which pushed even the high-performance machining centre almost to its limits. It was all about angularity and a few hundredths of a millimetre. After almost a week of programming, testing and measuring, the machining technicians had done it – but they also realised that the lack of air conditioning can definitely be a problem. "There were minimal deviations between the first parts and the parts produced from midday onwards. It was only when we brought the coolant up to temperature before the first cut that there was no more fluctuation," explains the head of CNC machining. Until May 2021, the Hermle milling centre had run on Saturdays, Sundays and public holidays – sometimes four days at a time. Since then, the situation has eased so that BWB-Betschart has capacity again for new products.
This gives Thomas Furger time to optimise the work processes with his employees. "Automation means flexibility so that we can redefine our process steps. Away from the stoic processing of orders, towards thinking in terms of assemblies," says Furger and adds: "We manufacture all the parts for a module one after the other and can then assemble the module directly." The key to flexibility is the robot. This is because BWB-Betschart only machines aluminium which is usually on the machine only for a short time. Pallet handling alone would not have been able to supply the 5-axis machining centre with blanks for an entire weekend. The RS 2 robot system packs both – pallets and individual workpieces – and therefore ensures non-stop operation.
A primary goal for Thomas Furger and his team is to minimise downtimes, achieve the expected precision and be able to react flexibly to repeat and individual orders. What it means to have a 5-axis machining centre from Gosheim in the machine park was only realised in the course of the year. "New customers came to us with orders which we would not have been able to accept due to the required precision or lack of capacity. With automation, we are more competitive compared to nearby countries, and we are becoming more attractive as an employer – also because of the robot," says Furger. Even internally, he notices how the operators and programmers are thinking ahead and increasingly making good use of the new flexibility. "I am sure that the investment will pay off in many ways."