LEAN Manufacturing Through Compact Machining Cell Advancements
By Steve Bond, National Sales Manager, RoboDrill, RoboCut and EDM Products, Methods Machine Tools, Inc. (www.methodsmachine.com)
Manufacturers, regardless of the products they produce, realize that to be successful in a global market, reducing costs and waste throughout their organization is critical. Amid recession, employers were faced with downsizing in an effort to maintain the bottom line and many turned to lean practices to help them survive. In this environment, it’s important to bolster your lean mindset and apply its concepts to automated metalworking operations, which requires integrating leading automation technology into your operations.
Although automating your production is not in itself lean manufacturing, the lean process can be an inherent part of your operations. Undoubtedly, automation can reduce waste whether from idle spindle time, lost time during set-up or for loading and unloading work pieces. By implementing lean practices in combination with automation, resourceful U.S. manufacturers can successfully compete by seeking manufacturing opportunities that are still difficult for other countries to execute. One key opportunity exists in manufacturing for the medical industry where parts often involve the use of challenging materials, complex shapes and extremely tight tolerances.
Automation on a Smaller Scale
In the past, automation was typically associated with streamlining high volume production. Robots performed a single task and changeovers were time-consuming, difficult and could adversely affect your bottom line. It’s no surprise that automation manufacturers were not immune to the effects of the recession as production levels plummeted. They were forced to rethink automated manufacturing and provide a solution that could adapt to low-volume production. Machine tool builders and robotic integrators were compelled to work closer than ever with fixture and tooling manufacturers to improve the changeover time to maintain the course of lean machining and to increase productivity of low volume operations. One example of this collaboration was the development for medical manufacturing of a robotic cell that minimized waste in set up and work flow.
FANUC, a leading supplier of robotic automation, and Methods Machine Tools, Inc. developed the cell, named FANUC RoboDrill Med Cell (Med Cell) that addresses all these elements and is highly efficient for low-volume operations.
Medical Manufacturing Cell Example
The Med Cell is designed so that raw goods are staged for efficient in-feed flow and accurate part fixturing in the machine tool by the robot. The Med Cell offers 5-axis machining capability using a tilt rotary table and is specifically geared toward short run production requirements, while maintaining a high level of unmanned operation. Med Cell provides lean automation as a complete pre-engineered, fully-integrated production machining cell for automating the loading, unloading and machining of medical device parts.
An off-the-shelf “EDM style” chuck that utilizes a common fixture base holds the raw material. The part is mounted on a pallet, fixtured accurately and rigidly in a corresponding tooling chuck that is air actuated, eliminating the need for new and redesigned fixturing. Then as machining begins, parts are machined completely for that particular application without interruption. Parts flow out of the cell for final packing or other required operations.
The entire process is automatic with minimal set-up required. When changeover is required for the next short run, simple modifications are made to the in-feed system and some minor adjustments performed before the next run. In many instances, manufacturers can run several different jobs in a single set up with little or no changeover, increasing productivity and profitability of their small lot parts of varying sizes and materials.
The Med Cell commonly produces complex medical components manufactured from stainless and cobalt chrome materials on a short run basis. In most cases these parts are exiting the machining cell completely finished. This machining cell technology is providing U.S. medical device suppliers with an affordable alternative to sending parts overseas.
Not surprisingly, lean is experienced in the total sense with FANUC. They understand the need for lean and even apply these principles to their own manufacturing. When building their Robodrill Milling machines, FANUC incorporates robotics to handle the castings and components, fixtures them in large sized “EDM style” chucks and machines components from raw material, completing final assembly with minimal change over.
Material Flow and Other Considerations
Robotic automation is available, cost-effective and is an ideal way to increase accuracy and productivity while reducing costs. However, simply adding a robot to your operations will not increase efficiency. Robotic loading in a cell requires significant consideration of raw material flow. Material handling can play a vital role in improving a manufacturing process and addressing this core issue is critical to implementing a lean automation cell. Well designed in-feed flow is critical to maintaining a lean automation cell; a robot is useless without incoming raw material.
Robot manufacturers have made material handling easy with simple-to-use software. Short run production with robotic loading and unloading is now a very affordable solution for the average job shop or a 1st or 2nd tier Medical OEM. After tackling the raw material flow issue, you must then consider handling, locating, fixturing, machining and removal of the product from the cell. Keeping a rapid material flow from raw goods to finished product will decrease product cycle times, increase productivity and capital equipment utilization, and decrease inventory. Smaller, customized part runs become economically feasible.
Taking advantage of simple robotic interfaces and innovative workholding is important, but manufacturers can now benefit from an entire automation “cell” by choosing solutions that include capabilities such as 5-axis machining. These lean cellular technologies hold the key to keeping our U.S. manufacturers competitive and profitable.
Lean Automation: Evolution to Profitability
Successful manufacturers know that to ensure their machining productivity and profitability, adopting a lean strategy is required to stay ahead of the competition. But it doesn’t end there; lean manufacturing is a continuum, an on-going evolution toward cost-effective innovation.
U.S. medical manufacturers who implement lean strategies, invest in the latest technology including robotics, can produce precision medical components with high accuracies out of tough materials, and remain competitive with overseas manufacturing. These affordable technological alternatives and lean processes will help keep U.S. medical manufacturing strong.
When evaluating the cost/ benefits be sure to test your assumptions on the value of off shore manufacturing. Overseas manufacturers can find it difficult to comply with stringent U.S. regulations and specifications for producing medical devices and orthopaedic components. Contact your local machine tool experts, challenge them with your need to apply automation in a lean environment and see for yourself how today’s technology can help you succeed in a competitive global market.