Bosch Rexroth has improved cost controls on more than 900 different tool assemblies it uses in its pump manufacturing facility in Fountain Inn, SC.
The company produces axial piston hydraulic pumps and valve housings for its drive products used in heavy equipment and agricultural products. The company operates two production facilities in the area that house more than 90 CNC machine tools, mostly from DMG MORI. Iron and steel from foundry suppliers are machined on four and five axis machining centres equipped with large tool storage capacities.
Cutting Tool Inventory Management
Due to the complex design of the products machined, the machining centres make use of an cutting tool inventory, which are mostly special designs to produce multiple diameters and other complex part features. They must be available immediately when needed.
Keeping accurate, timely track of engineering changes, item availability, as well as tool regrinds over the tool inventory and other indirect materials used on the production floor was deemed essential by Bosch Rexroth management. The goal was to minimize tool cost and process cost, improve throughput, and help assure consistently high part quality.
Bosch Rexroth already had Zoller tool presetters in the plants to provide accurate tool offsets for the machines in order to avoid crashes and other missteps. The ZOLLER presetter fulfilled that mission very well. However, the Technical Functions (TEF) department at Fountain Inn wanted to streamline the tool management system further.
Bosch Rexroth decided to invest in the Zoller Tool Management System (TMS), reducing what had been three software suites, design, inventory and measuring, into a single suite. Now just one software is doing the engineering, toolsetting and tool management.
Central data storage
Bosch Rexroth in Fountain Inn can manage tools from the office, CNC machines, Zoller Tool Organizers, and vending machines or directly at the presetting and measuring machine. All information is being managed by the single Zoller-TMS database.
And since it is modular, the functionality can be extended step by step going forward. Bosch Rexroth in Fountain Inn takes advantage of stored tool data and DIN4000 article characteristic information to optimize inventory cost control as well as tool production.
One of the keys for the TEF department is the tool storage management module that allows managing complete tool assemblies and tool components, and keeping accessory inventories up-to-date. The storage location management in the warehouse includes a 3D design kit which allows Bosch Rexroth to display current stock three-dimensionally, easily and quickly and assign items to a virtual bin location.
The stock-management module allows each item in the database a fast overview of bin location, in circulation and balance on hand in stores. Feedback on circulation and stock levels are available at the push of a button. This is a major assist for gaining manufacturing transparency to run production economically around the clock with the tool inventory when needed.
The Zoller system is also a tool for supporting quality and ensuring the transparency of the manufacturing processes. While providing simple import and export of tool usage data, as well as helping to integrate the various machines and departments.
Previously at Bosch Rexroth in Fountain Inn, one software ran the Zoller presetters and another software ran the engineering tool management. The software reported on the reality of the tools and the engineering software provided direction on how to make the tool.
There was a big problem in that the tool setter operators had their system and the engineers were working with another system.
There was always a challenge to make sure they could communicate with each other. Two databases meant two sets of information. So, Bosch Rexroth in Fountain Inn went with the Zoller Tool Management, (TMS) system which was not only on the presetters but is now used for tool engineering and on the machine tools. This way, a single set of data is available to operators, tool setters, and engineers.
Sounds simple, but it took some effort to create the system.
No more redundant data storage
The advantage is that the engineer is now fully in control of the tools right down to the machine if an engineer makes a change to a tool design, it is visible to everyone – starting with the adapter, which is placed in the ZOLLER, and ends with the cutting edge of the tool.
“We avoid duplicate data in multiple locations around the two production buildings,” points out Dave Morley, product manager for Zoller Tool Management Software. “Previously when the engineer made an update, he would have to tell the tool setter to update their record also, which took time and inevitably included some inaccuracy.
“We also started measuring every feature of the tools and added tolerance information,” he continued. “Since the complete record is kept, the engineer can see the history of the tool’s setup measurement results. Has the tool tolerance been in the mid-range most of the time or has it at times approached the limits? Previously, this information would not be available to the engineer anywhere, making it difficult to meaningfully improve the tool design or features according to proven performance.”
So we have the statistical measurement results of each tool assembly – which the engineer can pull up at his desk or at the machine tool. This allows us to make timely and very helpful corrections or improvements to the tool design, resulting in better machining capacity and reduced cycle times, and improved part quality. This also lets us identify and address root-cause machining quality issues.
Tribal knowledge no longer
At the plant, the rules are very strict if the tool is out of tolerance: it cannot be passed on to manufacturing. The engineer can investigate the issue before cutting is ever started.
One of the main advantages of the TMS is the centralization of what had been various centers of ‘tribal
knowledge’. It no longer resides in just one or two people. The engineer is truly in charge of the tool. Once set to defined tolerances, the tool will perform properly the first time it is used. Sometimes there is only 5 microns tolerance so there is no leniency.
An additional benefit to Bosch Rexroth is improved control of tool cost.
Optimization of tool deployment
The data collected will point the department to where to look for solutions. So far, tool breakage has gone down from an average of 15 tools per 1,000 parts produced, to under 8 tools per 1,000 parts produced.
With Zoller’s TMS, the TEF department also wanted to get an idea of how the tools are used in the machines.
The engineer can search the tool information through the Zoller TMS Tool Management Solutions at his desk, or at the presetters so he can make the connection between how the tool is set and how it performs. The operator scans his badge, scans the machine identity and inputs the reason code for the tool change. It was some adjustment, but it is visible which tools are changed the most, and for what reasons.
Bosch Rexroth can control inventory because the Zoller controls access to the tool component inventory which is optimized with the help of the tool assembly history provided by the Zoller Tool Management software. The software also controls access to the vending machines. The simple procedure at Fountain Inn allows users to look up the bill of material for any tool assembly at the vending machines, so they are accurately guided to the required components.
Keeping tools organized
Once the tools are designed, Zoller’s »toolOrganizer« enables Bosch Rexroth’s tool group to know the exact location of each and every tool or component. Interfaced directly to Zoller stock management, »toolOrganizer« helps keep track of tool components and other indirect materials. The exact location of a needed item is clearly indicated by flashing LEDs, providing a fail-safe check-out system for required components.
The vending machines also dispense personal protection items. Transaction time to pick up an item went from an average of 3 minutes to less than 45 seconds. We can also keep track of quantities, and frequency of use to ensure the availability of personal protection items for the employees at Bosch Rexroth in Fountain Inn. In general, over 40 per cdent of the over-the-counter transactions are now accomplished through vending machines without the involvement of tool crib personnel.
Increased production efficiency
Zoller has helped Bosch Rexroth to streamline tool design, product manufacturing, and tool quality. As a result, the plant has seen a reduction of quality issues and an increased production efficiency.
For Dave Morley, the job in Fountain Inn was a pleasure, from brainstorming and conceptualizing with the customer. “It was very gratifying to be part of Bosch Rexroth’s continuous improvement efforts for safe operation, high quality standards, and on time delivery of tooling to optimize work efficiency,” he said.