Lean production – we will support you.

DatumJuly 2013 SwissSchweizer rotary tableDrehtischtechnik technology NEWSLETTER

HaupttitelQuality alliance bla bla under bla the T1-520520Tyenbezeichnung varioX Swiss Cross

On the pL Lehmann table, a Schunk Vero S zero point system (with the red sealing lip) is installed. This driven system is ideally suited for fully automa- Untertitel 1 blabla bla ted machining tasks.

Clamping technology provider Gressel improves MC productivity by means of two-axis gear unit rotary table from pL Lehmann

Switzerland as a manufacturing country is conside- red to be kind of a quality promise. This is a fact which the workpiece clamping specialist Gressel from Aadorf (Canton of , ) is well aware of. Therefore, quality is essential not only for their products, but also for their equipment. In order to maximise productivity and flexibility, the compa- ny uses additional rotary tables by pL Lehmann from pL Lehmann gear unit rotary tables convince their user with their design and Bärau in Emmental (, Switzerland) on performance. Some important data on the T1-520520.ORR varioX two-a- two vertical machining centres (MCs). xis rotary table referred to in the article above: Centre height 300 mm (fix), weight 187 kg, max. spindle load 264 kg (528 kg with support), max. clamping torque 4th axis 2000 Nm and 5th axis 4000 Nm, axial force 4th Gressel AG, a Swiss company founded in 1923, is a typi- axis 40Bildlegende kN, mass moment bla blaof inertia bla 4th axis 0.8 kgm2 (for standard load 2 cal representative of essential Swiss qualities and character- with catalogue drive data) and 15 kgm (max. load with reduced drive data) istics: The innovative high-quality products are manufactured 2

Typical parts as they are finished completely by means of the T1-520520 two-axis rotary table in a single clamping operation. Figures: pL Lehmann

exclusively in the company’s central headquarters’ location in Since 2009, Gressel owns this Toyoda machine, on which a pL Lehmann Aadorf, but are also in great demand outside the Alpine re- table of the 400 series and, next to it, mechanical clamping devices are installed. It is used as demo machine for customer demonstrations, for the public. The products belong to a wide range of products which production of prototypes, sample parts and functional samples as well as has developed around the core business of workpiece clamp- an automated production system for series production parts. ing technology over the past 90 years. It comprises single, double and multi vices to be used on semi-automated/fully au- tomated universal milling machines and machining centres. In addition to this, individual workpiece clamping solutions and customer-specific concepts for automated production are part of the range of products. Here, the adaption of standard prod- ucts on pallets and clamping towers, also referred to as tomb- stones at Gressel AG, plays a vital role. But also conventional vices and hand tools for use in workshops have been sold suc- cessfully for very many years. A more recent highlight is the P60 workpiece storage for 60 small pallets, a fully automated complete solution to increase productivity.

In order to be able to ensure the quality of proven and new products on a continuous basis, Gressel AG produces With its large travel ranges (X: 1250 mm, Y and Z: 620 mm), the verti- with a very high degree of in-house manufacturing. Joerg cal AWEA-BAZ AF-1250 offers ideal conditions to place a vice next to the pL Lehmann gear unit rotary table. Maier, the managing director of Gressel AG, describes this approach as follows: «We receive deliveries of steel bars of 3 m in length, raw cast parts and standard parts. And the pallet system allows for horizontal machines that an un- rest of it, we do ourselves.» And he is aware of the resulting manned night shift can be run in addition to the two day advantages: «Thus, we keep the processing and machining shifts. The same applies to the vertical machining centres. knowhow in-house and are able to react to demanding cus- Since 2009, these machining centres also include a three- tomer requirements in a flexible manner.» axis Toyoda MC which is equipped with an additional gear unit table (fourth and fifth axis) from pL Lehmann. The ma- chine can be automatically equipped from the 60 spaces Innovations for products and production comprising P60 workpiece storage – a Gressel product. Jo- erg Maier explains: «Thus, we can machine our cubic small Since Gressel uses its own clamping technology in pro- parts around the clock. In addition to this, this machine also duction, the employees have developed a special sense for fulfils other tasks: It is used to test our new clamping and au- innovations regarding their product side. They know that tomation systems under real conditions as well as a demon- their customers (and they themselves) need to optimise ma- stration object for interested customers.» chining processes. «Today, a high level of efficiency is ab- solutely vital», says Joerg Maier and points out that most of the Swiss companies are suffering from the expensive Swiss Machining centre with high flexibility franc. «We, too, are thus forced to permanently improve our productivity. In order to achieve this goal, our own manufac- As the combination consisting of a three-axis machining turing facilities must be equipped with innovative products.» centre and a two-axis rotary table has proven its worth in everyday production, the decisions-makers decided last year Gressel provides their highly qualified specialist person- to purchase another system of the same type. The order con- nel with the most modern production and logistics equip- sisted of an AF-1250 vertical machining centre from AWEA, ment. A high level of automation with a Fastems shelf- and which is very similar to the Toyoda machine, with a iTNC 3

530 Heidenhain control system and a two-axis rotary table Lehmann rotary table as an ideal T1-520520.ORR varioX from pL Lehmann. It was delivered supplement completely by Walter Meier (FL) AG, MATO CNC-Maschi­ nen, www.matoag.ch, in Berneck (Switzerland). The decision to purchase the two-axis gear unit rotary ta- ble from pL Lehmann was not only based on the fact that it According to Joerg Maier, the managing director, the is a Swiss provider. Joerg Maier explains: «Of course, we machine selection was based on the following considera- have carried out an evaluation and found out that this rotary tions: «When we have found a successful system, we would table offers rigidity with enormous locking torques like vir­ like to have it twice – also for reasons of redundancy. We tually no other table. The retention force of the fourth axis is have not been able to buy the vertical Toyoda machine, 2000 N, whilst the retention force of the fifth axis is 4000 which we had purchased in , in Switzerland and, N. In this respect, this is the best solution for our purposes.» thus, decided to go for the AWEA which has a very similar design. In addition to this, it is also equipped with the same In addition to the performance data, Werner Schoch control system in order to be able to replace the programmes also praises the service: «The service is excellent. We have 1:1 in emergency situations.» already had very positive experiences. Once when the ma- chine had to be repaired following a collision, the repair was carried out very quickly. After only a week, the table was returned to us and was fully functional once again.»

In addition, the two companies have already known each other for a long time and appreciate the quality of each other’s products. Lehmann, too, is among the Gressel customers and uses, amongst other things, the mechanical zero point system gredoc in production.

Successful series production

Converts a three-axis machining centre into a productive five-axis machine: On the AWEA/pL Lehmann system, Gressel produc- the T1-520520.ORR varioX two-axis rotary table by pL Lehmann. es first and foremost clamping jaws of different widths and lengths. In most cases, the parts are up to the size of a fist and must be machined from five sides. Werner Schoch com- Both machines have a very large machine table which pares today’s production with the situation in former times: also allow mounting several mechanical clamping devic- «Before we used our automated centres, we had to machine es from our own production next to the installation of the each part on a normal three-axis machine in three clamping two-axis gear unit rotary table. Werner Schoch, head of the small parts machining department, explains the reason for this: «We are thus able to present our products to prospec- tive customers live in operation. In addition to this, we use the machine to a large extent for the machining of simple prototypes, spare parts, functional samples etc.. We are uti- lising the Lehmann rotary table particularly combined with automated equipping.»

The automated series production plays the major role for the new AWEA-BAZ AF-1250 configuration with the pL Lehmann rotary table T1-520520. Werner Schoch says: «This is why we have only mounted a normal vice next to the Lehmann table to ensure a certain level of flexibility. By almost 100 per cent, however, we are working in an un- manned and automated manner using the P60 workpiece storage on the Lehmann table.» The P60 workpiece storage developed by Gressel in collaboration with a partner company can be loaded with up to 60 clamping devices. A three-axis portal transports the devices between the pL Lehmann table and magazine. 4 operations. Using the additional fourth/fifth axis, our auto- mated workpiece storage and our clamping towers, we ma- Workpiece clamping technology from chine eight parts in a single clamping operation and, in this A to Z way, produce 96 jaws per unmanned night shift.» Today, Gressel AG, founded 90 years ago as a me- In order to achieve such a reduction in set-up times, Gres- chanical workshop, is a competent provider of high-qual- sel pursues the following approach: For the blanks to be ma- ity clamping devices used from conventional applications chined, clamping towers from the company’s own range of to automated processes. The Swiss company with approx. standard clamping products are configured. Each tower can 60 employees has both extensive knowhow as regards handle eight blanks and is stored in the P60 workpiece stor- workpiece clamping technology and expertise for develop- age. From that magazine, a three-axis portal handling sys- ing system solutions in the field of workpiece provisioning tem removes a clamping tower each and transports it to the and handling. The customer receives a properly function- pL Lehmann rotary table. ing solution which is «adjusted for any interface» – includ- ing installation, commissioning and service – from a single source. Until today, Gressel AG has been a family-owned company, is recognised as a market leader in Switzerland and is well established in the European industrialised coun- tries.

By means of the Heidenhain control system iTNC 530, the entire machine (including the two pL Lehmann axes) can be programmed for all five axes.

Here, it is taken up in the exact position by the Schunk Vero S zero point system, i.e. a driven system suitable for fully automated machining, which is mounted directly onto the pL Lehmann table. For the high-precision machining of the eight components, Gressel uses the fourth and fifth axis, each in the engaged condition. «This means that we are po- sitioning, fixing the axis in place, machining, rotating, fix- ing in place, machining. That is enough for our components. We do not require five-axis simultaneous machining – which, however, would also be possible using the Lehmann rotary table.» 5

Innovative Swiss rotary table technology

For many years, the strengths of pL LEHMANN include the high geometrical accuracy and rigidity of all rotary tables, also of the two-axis rotary tables in particular. By means of the «edition 2», the 500 series is now following the success of the 400 series: Due to targeted measures, it was possible to eliminate initial rigidity and accuracy weaknesses. Moreover, it has become much easier and more reliable to replace individual modules for these two- axis rotary tables. Thanks to the modular design, it is possi- ble to subsequently modify and/or expand the rotary table system at any time. Thus, the user can fulfil new machining tasks without the need to invest in a completely new rotary table. The serviceability was also improved significantly. Thus, for example, the reference point or the end position can be set or changed from the outside and without hav- ing to disassemble the rotary table for all versions. In terms of reliability, the pressure intensifier, in particular, which is compactly integrated in the housing experienced a deve­ lopment boost.

Since the pL Lehmann rotary tables are used on many different machine tools in combination with various CNC control units, pL LEHMANN provides a wide range of specific commissioning docu- ments. In addition to this, massive investments were made in the international sales and service network. At the moment, 16 representatives for 25 industrial- ised countries ensure an increasingly rapid supply of spare parts (or are undergoing development to do so) as well as a first-level service, in most cases, with their own service technicians who are trained by pL LEHMANN step by step.

Three-axis machines equipped with the 500 se- ries provide the ideal basis for the machining of many parts as required, for example, in the auto- motive, aviation and watch-making industries as well as in medical and dental technology. Our informative and comprehensive website www.lehmann-rotary-tables.com provides prospects with an insight into which options are available with the pL LEHMANN rotary tables.

Contacts: Peter Lehmann AG Gressel AG Walter Meier (FL) AG Bäraustrasse 43 Schützenstrasse 25 MATO CNC-Maschinen CH-3552 Bärau (Switzerland) CH-8355 Aadorf (Switzerland) Auer Strasse 36 Tel. +41 (0)34 409 66 66 Tel. +41 (0)52 368 16 16 CH-9442 Berneck (Switzerland) Fax +41 (0)34 409 66 00 Fax +41 (0)52 368 16 17 Tel. +41 (0)71 747 99 70 [email protected] [email protected] Fax +41 (0)71 747 99 72 www.lehmann-rotary-tables.com www.gressel.ch [email protected] www.matoag.ch