Більш ніж 15-річний досвід в технології лазерного зварювання, виробництво машин для автоматизування процесу зварювання, автоматичні системи затискання, повна автоматизація виробництва труб, починаючи від згортання і закінчуючи кінцевим продуктом.

The filter technology specialist EPE opts for a semi-automatic production centre with integrated rollforming and laser welding machines for its individual support tube production.

Experience and creativity associated with dedication and modern equipment - this summarizes the corporate philosophy of K. & H. Eppensteiner GmbH & Co. KG, 68775 Ketsch/Rhein, Germany, which develops and manufactures top-quality industrial filters and hydraulic accumulators for international distribution under the registered brand name EPE. Founded in 1926 and initially a metal spinning factory and toll manufacturer for sieves and similar products, it developed into a company which totals 230 employees today with an approximate annual turnover of 25 million Euros. Production is extremely high in the main factory in Ketsch and if necessary regional suppliers are called in. Production can be divided into two areas, namely the production of filters and filter elements.  Approximately 500,000 filter systems are manufactured a year, with quantities varying between 1 and 2,000 per batch. By combining production technology for individual filter elements and comprehensive machinery for the production of support tubes and metal parts with highly-trained personnel, every customer demand can be fulfilled flexibly and on schedule. The main focus is on quality as only first-class filter systems and hydraulic accumulators guarantee trouble-free machine operation. To ensure the highest level of quality and essential cost-effectiveness, K. & H. Eppensteiner GmbH & Co. KG places emphasis above all on in-house production using the latest technology and procedures. Targeted investments sustain lasting competitive strength and the company is always ready to adopt a new method. The latest example is a flexible production centre for the manufacture of individual filter support tubes.


Flexible production required for small series and customized parts 

Hubert Auer, Managing Director of K. & H. Eppensteiner, declared: "We have 20 product lines, with roughly three to five sizes within each line. There are also 20 different types of filter material, three different types of glue and five different types of sealing material, so that in the end several thousand variations are possible, which still have to be manufactured economically. When it came to rationalizing and modernizing the production of customized support tubes, we looked for a highly flexible solution which was mostly automated and included welding". Support tubes are generally manufactured from a coil or from sheet metal which is punched or perforated in-house and cut lengthwise and widthwise into blanks. These blanks can be either of tinplate, galvanized steel or stainless steel (1.4571 or 1.4404), which is very demanding on the joining technique. Contact was made with weil engineering gmbh from 79379 Müllheim, Germany, a well-known developer and manufacturer of modular machines and systems for the manufacture and welding of tubes and tube-like products.  The difficulty in the K. & H. Eppensteiner application was that the new tube production centre was to manufacture both support tubes for filters made in small series, and individual parts for special filters, namely short tubes up to a diameter of 75 mm and a length of 250 mm and support tubes from 76 to 400 mm in diameter and around 1,000 mm in length. weil engineering, the specialist for rollforming and welding machines, designed and developed a tailor-made production solution for Eppensteiner, which covers both mass and medium-scale production in addition to the entire range of customized filters and also offers capacity for toll manufacturing of perforated and non-perforated laser-welded tubes of small diameter.  

Individual filter support tube production on a standardized rollforming and laser-welding module 

The "fully-integrated but still open" production centre consists of the following system modules:

• a combined tube production machine, the Minimaster, for rollforming and laser-welding small, short tubes in the diameter range of 25 to 75 mm, for tube lengths ranging from 30 to 250 mm and a material thickness of 0.4 to 2.0 mm. The rollforming unit is fed by an integrated double destacker, which can automatically destack blanks from two magazines.
• a rollformer, RMA 400/1000 for rollforming tubes in the diameter range 74 to 400 mm, in lengths of up to max. 1,000 mm with a material thickness of 0.4 to 2.5 mm, with an integrated blank infeed table
• a laser longitudinal seam welding machine, Flexmaster 400, for tubes of up to 400 mm in diameter and max. 1,270 mm in length
• a 3.2 kW laser welding source TLF 3200
• and a beam switch which supplies both welding machines with just one laser source.

The production process in the support tube production centre is as follows: Depending on the size and batch of the support tube, perforated blanks, which have been cut to (developed) length, are placed on the infeed table of the stand-alone rollformer or in one of the stacking magazines of the combined tube production machine. Larger parts are rolled in the rollformer and are then manually fed into the adjacent laser longitudinal seam welding machine. This can be carried out by just one person operating several machines, in a time-saving, space-reduced procedure, as a tube can be welded or a blank can be placed on the infeed table of the rollforming machine whilst another is being rolled. With small (serial) products on the other hand, the operator can place up to three blank stacks in the magazine of the combined (rollforming/laser welding) tube production machine and let it run automatically.  

A universal flexible production centre with simple retooling possibilities

The aforementioned beam switch makes it possible to supply the Minimaster combined machine and the Flexmaster welding machine with just one laser source and operate them virtually simultaneously with just a slight time offset. The 3.2 kW laser covers the entire range of material to be welded at K. & H. Eppensteiner without difficulty and even offers reserve capacity. Laser welding offers enormous advantages particularly when it comes to welding perforations which facilitates the perforating and cutting of blanks considerably as no web is required. The combined rollforming and welding machine, Minimaster, along with the stand-alone rollformer, RMA, and the laser longitudinal seam welding machine, Flexmaster, can be retooled quickly and effortlessly without long production interruptions. Furthermore, the alternating rollforming and welding process makes it possible to retool a station whilst the other station continues production. For a product change-over, it is only necessary to change the upper rollers and welding rollers (Minimaster), upper rollers or slip-on tubes (RMA) or tool shells (Flexmaster), which thus limits both the time and cost of retooling. Finally, the Minimaster combined machine also enables laser welding of tubes which cannot be formed in the rollforming unit: these are formed on an external press and then fed manually into the welding unit. According to Hubert Auer, weil engineering's flexible tube production centre is ideal for Eppensteiner's requirements:  "We use it to manufacture support tubes in a material thickness of 0.3 to 2.5 mm and already use the Minimaster combined rollforming and welding machine for 70 to 80 part variations and the RMA stand-alone rollformer and Flexmaster longitudinal seam welding machine for more than 100 other variations. Thanks to the tube production centre, we have been able to widen product and delivery flexibility and are now able to satisfy customer demands even quicker. We have also been  able to achieve a further increase in quality due to perfect tube roundness (+/- 0.2 mm) and the excellent resistance of the laser weld seam, which for our customers signifies higher pressure loads and greater endurance".