Automating the toolroom

How does a shop that makes 4,000 toolholders a day effectively manage the toolholder assembly process to be as efficient and cost-effective as possible? In addition, how does the business manage to do the work in a consistent, accurate manner without depending on the ever-shrinking trained workforce available today?

Most people think about adding automation to the parts production side of a manufacturing operation, and this is of course a good thing to look at in general to become more efficient. However, how many companies look at the toolroom as a place where automation can play a key role in reducing costs and eliminating human interaction with the process while still providing the most accurate, consistent toolholder assembly in the production each and every time?

Igenhausen, Germany-based Haimer GmbH, an innovative global player in tool management for machine tools, asked itself this exact question for its own production, and it is convinced that production engineering needs to advance by implementing automation and digitization. (Haimer USA LLC is in Villa Park, Illinois.) This development is an established part of Haimer’s own production and also has found its way into the product range: from Industry 4.0-capable devices all the way up to the Automation Cube robotic cell, which can be scaled as required and is suitable for automated shrinking, presetting and balancing.

At IMTS 2022, Haimer showed a shrink-fit and presetting Automation Cube, which can incorporate a balancing machine if required. Image courtesy of Haimer

Efficient machining demands powerful machines and tools, “as well as high-precision toolholding technology, which ensures that the precision of the spindle is transferred from the spindle to the cutting edge,” said Andreas Haimer, managing director of Haimer GmbH.

That statement has many years of experience behind it. The company started 45 years ago as a machining service provider for the aerospace and die mold industry and soon began to develop high-precision toolholders for its own use.

Necessity of Automation

Haimer also has ample experience in automation. The Bavarian family company decided to equip its machine tools with robots for loading and unloading over 20 years ago. Since then, automation at the company has advanced swiftly as evidenced by manufacturing facilities at the headquarters in Igenhausen and in Motzenhofen, which is just six minutes away. Motzenhofen’s production plant in particular, which has been operating since 2018, was equipped from the beginning with numerous automated machining centers.

“If, like us, you depend on a very high level of in-house production completely made in Germany, or for other shops manufacturing in other high-cost manufacturing markets,” Andreas Haimer said, “there is no way you can avoid extensive digitization and automation. Otherwise we would not be able to keep up economically with our global competitors.”

Soft machining of toolholders is carried out in Motzenhofen, alongside all precision components for shrink-fit and balancing machines, including accessories. Up to 4,000 rotating toolholders can be turned and milled there per day before heat treatment, followed by µm-precise grinding in Igenhausen. Fine balancing also is conducted in Igenhausen using systems that have been developed in-house and are automated fully.

Not All Automation Is Complex

Among others, in Motzenhofen the company operates a totally automated manufacturing cell with several five-axis DMG Mori MillTap 700 machines. These highly dynamic vertical machining centers, which were installed at the beginning of 2019, are perfect for boring and milling components, such as BT30 and SK30 steep-taper toolholders.

“Here we use a simple plug-and-play complete solution, which includes a fully automated loading and unloading system using a Kuka robot,” said Manfred Mayr, who completed his apprenticeship at Haimer over 40 years ago and is responsible for about 100 machine tools as plant and production manager. “Blanks and the components that have been produced are placed in three drawers, each of which has around 78 positions. This ensures that unmanned production is possible for a minimum of eight hours up to 20 hours.”

He said the automation of four identical DMG Mori NHX 4000 machining centers, which are equipped with a pallet pool flexible manufacturing system, is considerably more demanding.

“There are 12 pallets, each with 400 places, ready to process various components” Mayr said. “This provides us with ideal flexibility — also when it comes to smaller batch sizes and short-notice changes in the production flow.”

The machines generally work highly productively and trouble-free in a three-shift operation supervised by just one employee. To operate the machines as autonomously as possible with a large variety of products, the company had the machines equipped with a tool magazine with 183 tool pots.

Mayr considers the fact that all tools for these machines are equipped with a radio frequency identification chip on the toolholder to be key. The chips are read in at a dedicated station when they are changed into the magazine. This means that the control digitally receives the correct tool data from Haimer’s Microset VIO linear presetter, eliminating input errors and mix-ups.