Shops looking for ways to improve productivity in traditional subtractive machining processes need look no further than ways to reduce setup time, improve spindle uptime, and implement CNC programming efficiencies. Shop managers overwhelmed by claims about the future of digitalization and Industry 4.0 can find ways to translate that exciting promise into their day-to-day operations—today.
One way would be to visit the newly expanded Siemens Technical Application Center (TAC) in Elk Grove Village, IL, for training in all things digital—from basic machining to advanced five-axis training and maintenance. Shops can visit Siemens’ TAC physically or via the Internet for training and learn how their shops can benefit from creating a virtual twin of all the steps taken to create a product using Siemens digital capability.
Another way shops can tap into the promise of the digital is by considering the experiences of GE Aviation and Boeing using Upskill’s Skylight platform on Glass Enterprise Edition wearable augmented reality glasses. Using the AR glasses provides a unique capability to perform processes on the shop floor that are extremely complicated (wiring Boeing Aircraft for example) or organized step-by-step to produce tightened bolts (on a GE jet engine) that must be torqued perfectly every time.
Here’s how companies large and small can benefit from the experience and models of these and other game-changing shop solutions.
Siemens Positions its TAC for Advanced Manufacturing
Siemens recently expanded its TAC to satisfy the demand for training to keep pace with digitalization and rapid changes in technology. According to Christopher Pollack, virtual TAC manager, “We created a mock mini job shop in the expanded TAC to demonstrate how Siemens’ digital capabilities take the process of manufacturing a part from inception all the way through to physical production. What we are doing is taking a big concept like digitalization and making it palatable and accessible at the shop-floor level.” In the mini job shop, Siemens designs a product using NX-CAM, engineers it and turns it into engineering drawings and files that are then handed-off via manufacturing SinuTrain software.
SinuTrain software for Sinumerik CNCs allows shops to create a virtual twin of a physical machine tool on a PC and evaluate all the processes that would normally be done on the shop floor during the setup process.
“The virtual twin allows shops to do all the things that they had been doing out on the shop floor and do them on the PC without downtime and interrupting production, said Pollack. “They can validate the process through simulation and then transfer programs to their machine tools using MindSphere, the Siemen’s cloud for industry.” MindSphere is a tool for virtual management of CNC machines, tooling use, and data transmission, that provides the ability to validate programs and monitor machine uptime and other key indicators, Pollack explained.
The obvious benefits are that rather than causing downtime on the machine tool, shops can evaluate and leverage processes in a virtual environment, something that they would normally do out at the machine tool. “Tying up machine tools on the shop floor is typical of job shops and low production run companies where they’re not doing heavy CAD/CAM-based production, but doing more conversational programming that requires typing on the machine. What we are demonstrating is the typical transition process from a prime or Tier One [supplier] that has designed a product and transitioned it out to the job shop,” said Pollack.
The Siemens TAC now occupies more than 3150 ft (293 m2 of dedicated space. The machine lab features three milling machines (one of which is five-axis), one turning center, a KUKA robotic cell, an NX-CAM training station, and two upgraded classrooms for hands-on training using Sinutrain software and Sinumerik CNC simulators. TAC training includes four different classes; one for service and maintenance and three levels of operator training. Level 1 focuses on basic milling and turning. Level 2 introduces G-code, and Level 3 is the most advanced, focusing on five-axis machining.
“We are creating a parallel training track for online training with webinars, streaming video, and online instructor-led training for its basic classes,” said Pollack. “We know that people will travel a lot farther for advanced five-axis training than they would for basic classes which can be effectively handled through online training.”
Wearable AR Technology Offers Heads Up for Maintenance
There’s a new way of looking at things out on the shop floor using wearable augmented reality smart glass technology and software. GE Aviation initiated an AR solution at its facility in Cincinnati.
In the aerospace industry, maintenance and assembly errors are costly, leading to lost productivity, delays in testing and customer deliveries, and potentially dangerous results if errors are not detected before engines are delivered to customers. GE Aviation found a new way to ensure that every bolt on its engines is tightened perfectly by using wearable smart AR technology that comprises Skylight software from Upskill, Glass Enterprise Edition smart glasses, and a Wi-Fi enabled Atlas-Copco Saltus MWR-85TA torque wrench.
Using Skylight on Glass, mechanics receive step-by-step guided instructions and images directly within their line of sight while performing different maintenance tasks. As the mechanics move through standard procedures and come to a step where they need to apply the torque wrench, Skylight alerts them through the smart glasses and then verifies the correct value in real-time before the mechanic can move on. Information is delivered to the technician in a hands-free, voice-activated heads up display.
The wearable AR technology is being used by workers for tightening B-nuts, critical fasteners used in aircraft engine fluid lines and hoses. The error in tightening a nut can be either making it too loose or too tight, requiring a maintenance do-over. Actual views of Skylight workflow show the background in red when torque applied hasn’t yet reached approved standards. As the final range of 132–150 lb (60–68 kg) of torque is reached, the background turns green. Workers use voice commands or swipe the side of Skylight on Glass to change views and move ahead or backwards through their next task.
Before the deployment of Skylight on Glass, workers followed instructions in paper binders or on a computer. To meet FAA-approved maintenance procedures, they regularly had to leave the engine, walk to a table or monitor, and review instructions to check their work. With Skylight, instructions as well as guided videos, animations and images are accessible at any time. A worker can even turn on a camera and call engineers or other support team members for “see what I see” assistance with difficult steps.
The AR technology also provides tracking results and records for chain of custody of an engine’s maintenance files. As each nut is finished, Skylight automatically records the final correct torque value. For further documentation, Skylight prompts the mechanic to take a photo of each installed B-nut for historical quality purposes. Those records are uploaded to a laptop or long-term storage for a record of the plant’s manufacturing system. On average, across all mechanics studies, efficiency improvements were between 8–11% and the team conducting the test believes its mechanics could see even greater efficiencies once the learning curve for use of the devices is mastered.
Wearables Give Boeing an AR View of Shop Floor
Boeing’s engineers have been able to cut production time by 25% using wearable AR smart glasses and Skylight software to wire new airplanes faster and with fewer errors. In every new Boeing 747-8 freighter, for example, there are 130 miles of wiring, representing thousands of miles of wiring and tens of thousands of hours of work every year.
Wiring is a special challenge with Boeing aircraft, with each model having its own wiring scheme. In the past, technicians used phone-book sized references full of diagrams. Laptops had the same basic problem: constant “look-away” interruptions as workers got directions and cross-checked diagrams and schematics.
Boeing’s engineering team discovered a new wearable solution—Glass Enterprise Edition and Skylight enterprise software from Upskill (formerly APX Labs). They began a pilot program with Skylight replacing those laptops and “phone books” of paper with instructions they need right in their viewfinder. There’s no need to look away or tap a laptop. A worker can move through multiple prompts with voice commands, the Glass touchpad, and the head tracking interface. A simple voice command like “local search 1-8-6-A” calls up the correct step-by-step schematic for every wire.
Bar code readers and the Glass cameras help identify and confirm wiring inventory. For extra help, workers turn on Skylight’s “see-what-I-see” video stream and share their view with engineers or other remote personnel. Technicians can also look at how-to videos in their field of view, keeping their hands free to do the work. Boeing calls the kind of improvement that wearable technology has delivered “step function change.” Rather than picking up seconds or minutes in build time, the 25% improvement in the wiring application is leading Boeing to look for other applications for wearable smart glass technology.
Electric Motors Require Attention
All plants, from job shops to large OEMs, face major challenges in maintaining production equipment, according to Kirk Graham, vice president of Volland Electric Equipment Corp. (Buffalo, NY). Volland repairs electro-mechanical equipment of all shapes and sizes, including fractional through 10,000-hp (7460-kW) AC and DC electric motors.
“Production demands trump maintenance concerns in too many cases these days,” said Graham. “While we don’t mind performing emergency repairs, we always make a concerted effort to assist our customers with predictive and preventative maintenance to avoid unplanned downtime.”
The run-to-failure approach can and should be avoided, and there any many inexpensive and practical ways to make this a reality. Here’s Graham’s advice:
“Electric motors should be inspected regularly. DC motors in particular require service on a regular basis, which could be on a daily, weekly, monthly, quarterly, annual or another interval.” There are many variables to consider when establishing service intervals, he said, including application/duty, environment, and ease of access. Some applications are more critical than others and have the capability of shutting down production or creating safety hazards. “In the case of maintaining hoist motors used for overhead material handling, safety is always paramount,” said Graham.
What can go wrong with a motor? Where to begin? Graham noted that bearing failures are responsible for about half of all electric motor failures, according to information from the Electrical Apparatus Service Association. Even electrical failures are more often the result of mechanical breakdown. Misalignment, over or under lubrication, unbalance and/or underlying structural problems can cause harmful vibration. Electrical failures do occur independently as a result of aging insulation, contamination, loss of adequate cooling air and voltage spikes, among other possible causes.
“Root cause failure analysis of electric motor failure is tricky business, but is one of the most important tasks we perform on a day-to-day basis,” Graham said. “Detailed communication with our customers is required, given that we expect to get to the bottom of the various failures we encounter.”
It’s important for end-users, either internally or on a contracted basis, to test, inspect, and maintain their motors. Careful documentation and trending of these results is required to maximize the benefit. “AC, DC and servomotors often require elaborate tests and documentation of their performance as well as maintenance and failure history, to ensure maximum reliability, he said. “We are able to detect mechanical problems early, sometimes through the use of vibration analysis, but often this can be as simple as having a discussion with the operator about an unusual noise.
“One of the best ways to head off problems with motors and related equipment is to empower your employees to volunteer information,” Graham added. “It can be reported in the form of an unusual noise, high vibration, poor performance or elevated temperature. When engaged in more sophisticated testing and preventative maintenance procedures, it is advisable to keep a master book or use other electronic means of documenting and trending the information. Quality employees care enough to communicate in the interest of preventing failures, and this communication should take place in written and/or by electronic means. Simply mentioning a potential issue is not usually enough to ensure action.”
Graham strongly recommends having spares on hand for all critical equipment. “Large assembly plants keep spares for motors, gear reducers, pumps and many other components critical for continuous operation. Often they are positioned right next to the in-service motor to minimize costly downtime in case of failure.” He added that you don’t always need to buy new products as spares. There is a great deal of surplus, rebuilt and used equipment on the market that can be used to economically plug holes in inventories of spare equipment and parts.
Shop Floor Savings Mount Up
Another way for shops to improve productivity is to make better use of the data their equipment produces. There’s time and money to be saved in the data that has been generated by processes, if only that data can become the basis for current operations.
That’s the promise of the Renishaw Equator flexible gage with intelligent process control (IPC) software. IPC software uses recent historical gaging data to determine process corrections with fully automated tool-offset updates. According to the company, IPC software improves capability in precision part machining, reduces setting and process adjustment time, and integrates with automation systems. The first release of the new IPC software allows connection to one or multiple machine tools, with direct Ethernet links from the Equator Controller to Fanuc, Mazak and Okuma CNC controls.
IPC software allows constant monitoring and adjustment of a machining operation, keeping part dimensions close to nominal and within process control limits. This means that any process drift is quickly corrected, improving part quality and manufacturing capability, along with reducing scrap. The proximity of the Equator gage to the CNC process allows measurement and process adjustment at the point of manufacture, avoiding time delays or relying on finished part (tailgate) inspection.
IPC software averages results across several parts to determine the true process mean for adjustment of each cutting tool. For process control purposes, only one machined feature per tool offset requires gaging, compared to many features for typical quality assurance (QA) applications. The frequency and control of offset updates can be configured on a feature-by-feature basis depending on design tolerances, process variation, and tool wear rates. An Equator gaging system can be connected to one or more CNC machine tools so that parts from different machines can be gaged on one Equator, with the offset updates being sent to the corresponding machine provided that part/machine identification is provided.