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A manufacturer can look at a turnkey unit as a way to solve a variety of measuring issues. Whether for existing products or a new product, turnkey systems are often a way to add production capacity in a limited space. A turnkey unit has a small footprint when compared to installing a new production line or adding multiple measuring stations.
These units can be outfitted to run in a high-speed production line with robots moving parts onto and off of loading tables. They can be used in a work cell-manufacturing environment. Turnkey systems can be made up of an individual measuring device such as a coordinate measuring machine (CMM), vision system or laser system, or multiple devices can be packaged together and driven by sophisticated software.
Turnkey systems are often ready to use "right out of the box." They are generally automatic and easy to use so extensive training is not
necessary-an important factor considering the difficulty many employers are having finding trained workers.
For manufacturers, perhaps the best reason to look to a turnkey measuring system is that the onus of making it all work is on the turnkey supplier-the company with the expertise to think both inside and outside the turnkey box.
Turnkey units can be used in as wide a variety of applications as can be conceived. For instance, International Truck and Engine Corp., (Warrenville, IL) the world's largest producer of mid-range diesel engines, turned to a CMM-based turnkey system when it wanted to improve processes at two of its plants. By doing so, the plants achieved new levels of quality verification, system productivity and flexibility. At the same time, the company says the turnkey system made its manufacturing processes more productive.
The company revamped production at its plants in Huntsville, AL, and Indianapolis. The plants produce the next generation V-8 diesel engine for International brand trucks.
At each location, diesel engines make their way through machining and assembly production lines that are nearly one mile long. The process includes multiple integrated manufacturing quality verification stations where line operators conduct quality checks. In addition to the integrated quality verification checkpoints, components undergo random in-process and final product inspections using CMMs.
When International developed the manufacturing processes at its Huntsville and Indianapolis facilities, it incorporated a fully automated, quality verification process for engine crankcases, cylinder heads and crankshafts that combine Prismo CMMs from Carl Zeiss IMT Corp. (Maple Grove, MN) and an overhead gantry loading system from Fibro Inc. (Rockford, IL). The verification system measures part dimensions to ensure accurate machining, supporting process control and production volume objectives.
"We knew that there were automated CMMs on the market that incorporated loading systems using automated pallets or pick-and-place robotics, but we required a solution that would increase throughput," says Donald Brown, International's senior manufacturing engineer. "The system had to fully automate the CMM inspection process, optimize manpower and provide efficient, accurate inspections on production lines."
Each CMM is equipped with 18 probe configurations and measurement programs to verify the thousands of features on each crankcase, cylinder head and crankshaft. Measurement time depends on process or product complexity with results for each feature downloaded and sent electronically to the manufacturing line's real-time shop-floor application to let machine operators know when to change worn tools or make alignment adjustments.
The Huntsville plant uses four automated CMMs and the Indianapolis facility uses three automated CMMs. The automated systems use overhead gantry loading and computerized controls and each manufacturing process is verified at a frequency documented by the control plan for each process.
Components are loaded and unloaded at a station outside an environmentally controlled enclosure. Parts are loaded on the load shuttle pallet that hold the crankcase, cylinder head and crankshaft. Operators enter sample data at the load control station, using operator prompts and bar codes. The load shuttle delivers the sample into the room and to the gantry system through an automated door. The gantry then picks the part from the load shuttle and places the sample in one of three locations on each storage seat. As many as 24 samples can be loaded to fill the system. The system selects samples by priority and order and then delivers the sample either to the next available CMM shuttle or to a selected CMM. Based on the sample data entered, the CMM performs the specified program and returns the CMM shuttle to the gantry for post-inspection storage. The operator receives the report via the intranet.
"We believed a single overhead gantry system would enable us to load parts for inspection on a CMM without disrupting the routines of the other CMMs," Brown says. "Unlike pick-and-place robotics, the overhead gantry can handle the larger part size and weight to easily transfer the part from the queue to one of the four CMMs."
Turnkey for NDT application
Turnkey units are not all the same, and certainly not all of them feature a CMM. An example of a nondestructive testing scenario can be seen at the power tools division of Black & Decker (Towson, MD). The company uses a turnkey image analysis system from Clemex Technologies Inc. (Longueuil, Canada) for quality inspection and research and development. The turnkey system consists of a computer, motorized stage, microscope, camera, printer and two monitors. One monitor is used to display a high-resolution image and the other is used to develop imaging routines.
The company uses the multipurpose system for a variety of projects. Rich Williams, senior materials technician at Black & Decker says, "We work very closely with key product development teams, providing them with detailed image analysis reports in our evaluation of their prototypes."
In performing micro-structural evaluation of samples, the metallurgical lab conducts a variety of tests that include the analysis of steel alloy and powder-metal gears, thickness checks of titanium and zinc plating, and carbide analysis. To perform these tests, a lab technician prepares samples, which may include cutting, mounting and polishing before the actual analysis. Following this step, the technician places the sample on the microscope and runs a predetermined imaging routine or develops a custom routine in order to quantify the image. Characteristics such as volume fractions, particle sizes, or other dimensions may be analyzed by object or field. The data and image is then presented in a report and submitted to product development teams for further prototyping.
In addition to providing accurate results quickly, the image analysis system offers other advantages over traditional methods. "Previous to using image analysis, our lab was spending money on film, which could be better spent elsewhere. With digital imaging, not only do we get better results, we can capture an unlimited number of images and not have to worry about film cost," says Williams.
Previously, the company would spend about $3,000 to $4,000 per year on film, but they took a limited number of images. With the new system, they take about 2,000 photos per year. The results are more accurate because the image analysis is more automated and eliminates potential human error. For example, when conducting a grain-size analysis, human operators would evaluate the micro-structural composition of the sample as seen in the microscope with standard industry charts to gage for quality, a time- consuming and less-accurate method.
As can be seen by these two vastly different examples, a turnkey system can have many uses. The turnkey units can be placed in-process, as in a go-no go scenario, in a closed-loop configuration or as a post-process station. The unit can be designed with robotic material handling or may require an operator to upload and offload parts. A turnkey system can replace multiple measuring stations because it can be built to handle diverse measuring and inspection requirements. They can be used to take a labor-intensive measuring job, or a job that requires extensive employee training, and automatically perform the task in a high-speed inspection environment.
Sidebar: Tech Tips
1. Jobs that were once labor intensive and somewhat inefficient can be handled automatically in a turnkey system.
2. A turnkey system is often built so that it is ‘plug and play' for the manufacturer.
3. The turnkey system may include proprietary equipment, or it may include an integration of equipment and software from multiple vendors.