CGTech’s VERICUT simulation and optimization software provides a crucial step on the MAN Energy Solutions digital manufacturing journey. At the company’s Danish manufacturing facility, the globally renowned software has significantly reduced product prove-out times and minimised scrap levels, helping MAN Energy Solutions deliver on the promise to its customers of a sustainable future.
MAN Energy Solutions is a multinational company that produces large-bore diesel engines and turbomachinery for marine and stationary applications, including marine propulsion systems, power plant applications and turbochargers. The company was formed in 2010 from the merger of MAN Diesel and MAN Turbo and is a subsidiary of the Volkswagen Group.
Employing a total of around 14,000 people at 120 sites across the globe, its T35 manufacturing facility located just a few miles away from Copenhagen airport in Denmark produces fuel injection systems that require extremely tight tolerances components for new installs and service life replacement as well as refurbishment and retrofit of older vessels and static sites.
Until recently this facility had lacked investment in digital manufacturing, as Process Owner of Digital Manufacturing, Mikkel Jon Hass, recalls: “In comparison to other sites we were behind in terms of technology and investment because there was no strategy for this segment. We just followed the same tried and tested path to produce components as a typical batch flow engineering machine shop.”
That all changed when, just 3 years ago, a new management team began to influence the direction of the business and focus on its future with fresh ideas. “Around the start of 2018 the new management team established our journey towards digital manufacturing. New manufacturing equipment started to be installed and my role was created. It is an unusual job title but is confirmation that times have changed as just a few years ago it was an unknown function. I wanted a title that not only reflected my scope but also shows that the business is focused on digital manufacturing,” says Mikkel Jon Hass.
His appointment marked the first time the business had anyone tasked with prioritising the changes to bring about digital manufacturing. During the investigative process of the various requirements of the business Mikkel Jon Hass discovered that the company had an established preferred IT provider strategy that determined software platforms.
He says: “Luckily, VERICUT was also on the list which made it a lot easier, So, the digital footprint was set without any further discussion. VERICUT was the simulation system chosen globally by our German headquarter facilities in Augsburg where they have been using VERICUT for many years.”
As such the tolerances on the parts mostly produced from a tool steel with very specific attributes are very tight. To achieve these levels the company operates very high specification machine tools, from multi axis machining and turning centres to super finishing systems and jig grinders.
The machine shop runs on a Continental five-shift system, but the CAM programmers are available for the day shift which is when prove-out occurs. If the prove out is not completed within one shift then the following two shifts can’t progress or make parts. This was one of the key reasons for investing in VERICUT and the software has helped significantly.
Providing some background, Mikkel Jon Hass, states: “Our machines and processes are very complicated and that leads to many issues. Honed parts are often held to 3 micron on a parallel bore with a surface finish of 0.2 Ra that is at the absolute limits of what the machines can achieve.
“Before using VERICUT it would be difficult to quantify the time required to prove-out any new parts. We knew we had to get the new parts running, but nobody knew how long it would take, there was no transparency. They would allow months to get from the design phase to proven and ready for production.
Now prove-out has been reduced from typically taking around 5 days, a whole week effectively, to just a few hours. “We recently had a prototype design go through that had six redesigns before being proven in VERICUT, machined and measured in the quality department in just 24 hours,” Mikkel Jon Hass says.
He continues: “With VERICUT we aim for the prove-out to be a factor of the cycle time, so for a 1 hour cycle time we want to prove out in 2.5 hours; we are currently at 3 to 4 hours. This is the goal for us going forward, so everyone has to be open to new ideas and new methods.”
Multi axis multiple functionality machine tools such as the two new DMG-Mori CTX Gamma 2000 machines represent the future strategy of the business. Where possible it will opt for two turret twin spindle machines with a B-axis, and a further three machines are already on order to replace older turning centres.
“For the first few years the new machines were operated just for turning,” recalls Mikkel Jon Hass. “No one could handle the programming complexities of the milling and drilling capabilities as they are very difficult to program safely. There are many opportunities for collisions between the tools, fixturing, machine structure and the workpiece.”
A point that Lee Fowkes, Country Sales Manager for CGTech, adds to: “We see many customers investing significant sums in large mill-turn centres and they simply do not achieve the expected productivity levels because they do not have either the skills or the mindset to unlock the full potential of these machines. I call it the ‘myth of mill-turn productivity’.”
Now, VERICUT is used to verify the post processed CAM program to ensure it will run safely without crashing and the staff to run these machines have been specially selected, not by skilled capability but by attitude and willingness to adopt new concepts.
Prior to using VERICUT machine tool crashes were seen as part of the operational risk, these were not usually identified during the prove-out as all the parameters are backed off and the process is being monitored very closely. However, when the parts went to production errors that didn’t arise during the early stages were often highlighted. Part of the justification and ROI for investing in VERICUT software came from the expected saving of one spindle per year. “We have had several virtual crashes in VERICUT but nothing on the physical machines,” confirms Mikkel Jon Hass. “However, the real savings come from the prove-out time achieved.”
Another key part of VERICUT software that is supporting MAN ES is the Auto-Diff module. It enables the programmers to compare a CAD design model to a VERICUT simulation to automatically detect differences. Using this module in the production process can identify incorrectly machined areas.
Says Mikkel Jon Hass: “The process is to turn the blank to size and then mill the prismatic features and so on with following sequential operations. Some of this will be removed by the increased mill-turn capacity where we probe the part on the machine, but for some families of parts it is still the most effective route. Previously, if the parts required say four turning operations and two milling operation and an error was made at any stage then it would not be detected until the part had been finished. This wasted time and effort, effectively making scrap.
“Now we are updating out manufacturing documents in NX and using Auto-Diff in VERICUT to check the part stock for each stage of the manufacturing process. It is a great tool to provide confidence in the process and eliminate the risk of bad parts being unnecessarily progressed. If you make scrap you have to make the part again, but it is better to catch the error as early on as possible to save your resources. Many of our parts are similar with just small detail changes and these can easily go unnoticed, which is why Auto-Diff is important,”
Advanced machining centres from Heckert and Heller are also modelled in VERICUT and now they will not run any program without it being verified first in the software. As Mikkel Jon Hass says: “There are too many variables and opportunities for failure, so we have to rely on something we know is safe.”
Thanks to CGTech’s Danish reseller, a total of 10 of the advanced machine tools on the shop floor at MAN-ES are accurately modelled in VERICUT. As always the models needed to be fully proven to reflect the actual physical machines as Sales Manager, Henrik Iverson, points out: “During the checking of the models we had some programs from a prior CAM-system, some programmed by hand at the machine’s controller and some from NX presenting many scenarios and many challenges.
“Of course, every CNC machine on the shop floor should be verified to provide the process security required by MAN-ES. Losing legacy programming methods is another cause of headaches, not just for MAN-ES but for many machine shops. So, the ability of VERICUT to read NC programs that are hand-written at the controller or generated by the latest post processor, and even part programs being moved from older machines to newer, more capable machine tools is vital to the safety of the machines and the workpieces.”
One of the new machine tools, a DMG-Mori NTX 1000, with similar kinematics to those on the shop floor, but a smaller working envelope, has already been modelled in VERICUT. “Space is tight on these machines, so you have to check toolholders and so on, we had to buy special holders due to the lack of space. And, we can get our part production programs ready prior to the machine installation. It avoids the protracted installation sequence that is too often followed when a complex new machine is installed,” states Mikkel Jon Hass.
Accurate machining cycle times simulated by VERICUT are providing better control for various cost centres within the business and are fed into the company’s SAP ERP system. Mikkel Jon Hass concludes: “We make mistakes, every machine shop does. So, we have closed the loop to make sure we can learn from these mistakes. I try not to attend the prove out of my programs because I have confidence in VERICUT. But the shop floor has a list of potential errors so they can note if anything does not go as planned, these are assessed, and I share them with the head of production and the management team. Some are my mistakes, but I am not ashamed of them, we only learn by making mistakes. The only negative element of a mistake is if you make the same one again and again. VERICUT is only for those of us that make mistakes. It provides business transparency that is appreciated by the management.”