Embedded within its Catia CAD system, environmental control systems manufacturer, Eminox Limited uses Radan’s powerful CAM functions to ensure its profiled components contained on nested sheets are right first time, every time.
Established over 30 years ago Hexadex is a privately-owned group with an annual turnover of just under £100 million. Part of this successful group, Eminox, manufactures exhausts and emission control systems. From its facilities in Gainsborough, Lincolnshire the company focuses on systems for commercial road transport vehicles, passenger service vehicles, off highway manufacturers and rail industry customers in both the OEM and retrofit markets. While a sister company in Sweden produces high volume OEM exhaust systems for established manufacturers such as Scania, Volvo and Mercedes-Benz.
Around 200 are employed at Eminox with 100 staff on the shopfloor split between two shifts. The company’s philosophy has always been to invest in the best equipment and software available, with a large percentage of profit re-invested in the business. This is why the company uses Planit Software’s advanced Radan CAD/CAM system to program its laser profiling machines.
CAD support engineer, John Rogers, explains: “We are a relatively low volume but high variety manufacturer, ranging from a one off system designed bespoke for a customer to a call off of up to 1000 units per annum. Because of the variety of parts we run through the workshop we need a robust method of programming the laser machines. We can’t afford to have someone sat all day doing a program for one nest. We might do up to 200 nests per day and the part variety means that the chances of us ever running the same nest twice are very slight. There is no requirement for a nest history and it is so easy to generate a new one. It is quicker to make a new one than to try to find an old file. I believe Radan’s nesting functions are among the most powerful of any CAM system available, we know because we push them to the limit.”
Eminox’s ERP system generates schedules so that the production department knows what to cut, while the design capability comes from Catia with around 14 CAD seats used by the company. The designers create an exhaust system and once the design has been committed to manufacturing the sheetmetal will not be touched by human hands until the profiled part is taken off the laser for rolling or bending. As John Rogers says: “There is no inspection at laser production as we expect it to be right first time – there is no margin for error.”
The Catia CAD system flattens the design and informs the ERP system that it will require laser profiling. The 2D profile is then presented to Radan in a DXF format, with the software running seamlessly behind the scenes. Radan interrogates the profile to measure its surface area and ensure it has a closed profile for the laser to process. The area calculation in Radan ensures that the correct view of the part has been used for the profile as it checks with the Catia calculation and the two should match within tolerance bands set by John Rogers. The software will highlight if the part cannot be made and the designer can view any problems found.
“We have to ensure that what goes to the laser can be produced without any problems so every part transferred from design to the ERP system for production will be checked with Radan to ensure there are no problems logged against it. If there are any issues the software will not allow the part to be transferred. The designer has to correct any issues, such as open contours. Of course, sometimes we will want an open contour and in Radan we can define these profiles with different colours which allows us to select these and accept them because it is what the design calls for,” says John Rogers.
The checks are there to stop corrupt or invalid geometry getting through and the designer is completely unaware that Radan is running in the background of Catia, and does not even need to know how to use the software. The CAD software is completely integrated with Radan using VBA tools, and is able to open inside Catia.
John Rogers comments: “We used to have to take the Catia files into an Autocad environment as a DXF file, which lost all the synchronisation between the parts. Now the Radan symbol file is linked back to the Catia file, so any modifications will flush through the system providing us with hidden intelligence.”
Most component nests are cut from stainless steel blanks with a nominal sheet size of 2500 by 1250 mm, while the thickness varies depending on the function of the finished part. Schedules are put together on the shopfloor for the different laser machines. Here Radan is used to create a PDF set up sheet of the nest and also details where the operator needs to stick bar code labels on the part for full traceability. The bar codes are used for parts picking from the stores prior to assembly.
The schedule list has to consider the run time of the nests and also try to minimise the lens changes required for different sheet thicknesses. The new laser currently being installed has a faster lens changing capability to increase the flexibility even further.
Eminox operate the latest release of Radan which offers a powerful Project Nesting control used by the company to place additional Kanban parts in to spaces available on nested sheets. For Eminox, these Kanban parts are regularly used components that are common to a lot of the designs produced.
“Radan allows us to put extra parts across the production run for the day. At the end of the run, when the next shift starts with its high priority work any extras that have not been consumed will be placed on the sheets with the high priority parts. If we don’t have enough Kanban parts we will maximise remnant stock so that we keep the material utilisation high. We want it automated as much as possible but it is not always feasible so nest manager allows the flexibility to manually fit more parts on a sheet,” states John Rogers.
He continues: “We have seen a 5 per cent reduction in material usage which we measure as scrap allowance, and we might be able to squeeze some more out. We also believe the up time on the lasers has increased in terms of collision avoidance due to better program control.”
Radan provides very accurate cycle times so the company has an exact measure of much capacity is available, with run time and sheet utilisation data supplied to the ERP system for reporting functions. “We have been using Radan as an operation tool but the plan is to use it as a strategic tactical planning tool for efficiency gains. The software’s integration into Catia and our ERP system allows Radan to do far more than could be done with our previous CAM software,” John Rogers concludes.