When a retrofit is the better investment

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customer-service

When a retrofit is the better investment

It turned out that giving the existing machine a second life, rather than replacing it, was the better solution. Through a comprehensive retrofit, Starrag made a tried-and-tested vertical lathe ready for the future – and turned NEUMAN & ESSER into a committed retrofit user.

”The required capacity was available, and the machine’s mechanical components were still in perfectly solid condition,“ recalls Simon Prell, Head of Machining at the NEUMAN & ESSER machine shop in Übach-Palenberg near Aachen, Germany (NEA GROUP).

Retrofit instead of buying new

In fact, the replacement of the 26-year-old Dörries CONTUMAT VCE 2000/180 had already been planned and budgeted for. But the conditions were far from ideal. Replacing it would have required extensive foundation work and a production shutdown of at least six months. In close collaboration with Starrag, the decision was made to carry out a comprehensive retrofit. Ultimately, confidence in Starrag’s retrofit expertise was the deciding factor. The company manufactures compressors for applications including technical gases and the hydrogen industry. It also manufactures machinery and equipment for mechanical process engineering. Mechanical manufacturing primarily produces large, custom-made components for one-off items and small production runs. Consequently, the requirements for precision, reliability, and availability of machine tools are correspondingly high.

Starrag technology: proven in complete machining

For many years, the machine shop has relied on Starrag machine tools for its mechanical manufacturing operations. They have proven themselves in the complete machining of complex machine components – such as the complete machining of crankshaft housings weighing several metric tons for piston compressors on a Droop+Rein T series gantry machining center, which has been in continuous three-shift operation since 2011.

The Dörries CONTUMAT VCE 2000/180 has proven itself to be just as reliable – and has been doing so for more than a quarter of a century. This compact single-column vertical lathe machines large rotationally symmetric workpieces such as cylinders, cylinder liners, and pistons, as well as complex replacement and repair parts. The range extends from solid cylinders to thin-walled cylinder liners with strict requirements for wall thickness accuracy. In addition, there are pistons with diameters of up to 1.3 meters. Whether it’s new machinery, spare parts manufacturing, or repairs – tolerances in the hundredths-of-a-millimeter range are required for both inner and outer diameters. Its high precision, robustness, and – above all – its exceptional long-term accuracy made the machine the ideal candidate for a retrofit.

It’s no coincidence: The vertical lathe had proven its worth in daily use for decades. Its solid cast components form a robust machine base that can handle both high cutting forces and machining operations in the hundredths-of-a-millimeter range. This combination of precision and durability has proven its worth, especially in the demanding spare parts and repair business.

Focus on support and control

The retrofit focused on the two assemblies where the machine’s age was becoming increasingly apparent – the tool carrier unit of the vertical lathe (support) and the control system. The support system at the Starrag plant in Mönchengladbach, Germany, was completely overhauled and updated to the latest state of the art, and, among other things, equipped with a new Z-axis drive. At the same time, the machine was equipped with a completely new electrical system featuring SINUMERIK ONE, new drives, measuring systems, a switchgear, and a control panel.

In collaboration with the maintenance department, the modernization measures were designed early on to ensure cost-effectiveness and minimal downtime. “Support and control – those were the two areas where we saw our main challenges,“ says Simon Prell. ”The fact that we focused specifically on these areas has resulted in the machine now being in like-new condition again.“

The focus was not on replacing an older control system. In collaboration with Starrag, the vertical lathe was equipped with a control system that closely mirrors that of the newer machine tools in the plant. As a result, operators today can switch between machines with virtually no adjustment period. “Job rotation has become possible,“ says Simon Prell. ”It’s incredibly easy for operators to switch to a different machine and start using it right away.“ He rates the implementation as “absolutely satisfactory.“ By 2027, the company plans to convert all of its machine tools to a standardized Siemens control concept.

Get up and running immediately thanks to a quick restart

The success of the retrofit became apparent immediately after commissioning. Despite the completely new control system, the machine shop had the vertical lathe back in full production as early as the following week. After a brief on-site training session, the operators were able to get to work effectively straight away. Simon Prell says, “We were productive right away. That was actually the biggest benefit for me.“ The unavoidable downtime was limited to just twelve weeks. For Simon Prell, another key to success was the close collaboration between the Starrag retrofit specialists and the company’s own maintenance team. “It’s always very important to us that there’s good cooperation between our maintenance team and the service representative,“ he emphasizes. The key factors here are the available expertise and “clear communication on an equal footing.“

The real test didn’t begin until after the system went live – during day-to-day production operations. However, spectacular increases in productivity were not the goal of the retrofit either. Even before the modernization, the vertical lathe was operating at a high level. ”We were never at a low level. But we’ve really stepped it up a notch,“ Simon Prell sums up. He sees improvements mainly in productivity, machine availability, ease of use, and machining quality. However, he says that it is difficult to provide specific figures. ”You have to be realistic about that. We’re looking at an improvement in the single-digit percentage range.“ He adds that, as a typical custom manufacturer with small batch sizes, it is difficult to quantify such effects precisely anyway. For NEUMAN & ESSER, the consistently high quality of the workpieces is more important than the actual processing time.

Satisfied employees increase productivity

This reliability really pays off, especially in the spare parts and repair business. Unlike in mass production, no two orders are alike. ”I’ve got great confidence in the machine and its reliability,” says Simon Prell, describing his confidence in the modernized vertical lathe. ”It impresses with its solid and sturdy construction.“ His team, too, still really enjoys working on the machine. The key factors are the machine’s ease of access, spacious work surfaces, and high level of user-friendliness. For the department head, the successful retrofit therefore has significance that extends far beyond this single project. While modernization was rarely considered in the past, it is now an integral part of the company’s investment strategy. ”It will remain a path forward in the future – and always an option,“ says Simon Prell. This approach is particularly effective for tried-and-tested machines, as it helps maintain productivity, make optimal use of existing infrastructure, and significantly reduce downtime compared to a new installation. Following his positive experiences with grinding and now also with vertical turning, he intends to continue down this path.

“ We were productive right away. That was actually the biggest benefit for me.“ - Simon Prell, Head of Machining, NEUMAN & ESSER

Sometimes a retrofit is all it takes

Starrag is an important partner on this journey. Following the successful retrofit of the Dörries vertical lathe, the next modernization project is already on the horizon – a Scharmann boring mill. For the head of production, this is a logical step. If the mechanical components are in good working order, a new machine isn’t necessarily required. In such cases, a retrofit may be the more cost-effective and, at the same time, high-performance solution.