Without regular inspection and maintenance, CNC machines will gradually lose positioning accuracy and introduce errors over time. To process complex, high-value aircraft fuselage components, BAE Systems uses the wireless ballbar system to provide the required machine diagnostic data to maximize product quality and productivity.
BAE Systems employee Jim Walsh is using the Renishaw QC20-W ballbar
background
The manufacture of fuselage components for modern aircraft has stringent requirements for accuracy and quality consistency. The life expectancy of the fuselage assembly must match the life expectancy of the aircraft, so ensuring production quality and reliability is critical in the processing of metals and composites.
BAE Systems, a global defense, aerospace and security company, produces a variety of key fuselage components for European Typhoon fighters (a twin-engine, delta-wing multi-role fighter). Since its inauguration in 2003, this highly mobile fighter has been included in the air force sequence of many countries around the world.
At the state-of-the-art manufacturing facility at Summersbury Airport near Blackburn, England, more than 80 CNC machine tools from BAE Systems are operating at high speeds, producing a variety of high-value fuselage components for typhoon fighters and other aircraft.
In order to ensure consistent quality, minimize material waste and increase production efficiency, maintaining the performance and output of five-axis machines has become one of the main responsibilities of the company's production line engineers.
European Typhoon fighter in flight (Photo copyright: BAE Systems)
Therefore, it is very important to perform CNC machine inspection and calibration checks on a regular basis. BAE Systems used Renishaw's QC10 ballbar machine diagnostics system long before. Since then, in order to increase flexibility and ease of use, they have begun to use the second generation of wireless ballbar system.
QC20-W ballbar system
If the positioning performance of the CNC machine tool is ideal, then in any two-axis combination, the circular interpolation will exactly match the set circular path. The QC20-W wireless ballbar provides a way to compare actual trajectories and set trajectories to determine if there is an error.
Renishaw QC20-W ballbar
The ballbar contains a high-precision linear sensor with a precision ball at each end, which is fixed to two precision magnetic bowls: one magnetic bowl is mounted on the machine table and the other is mounted on the machine spindle. In this layout, the club is capable of measuring subtle changes in radius when the CNC machine is operating in a set circular path.
Signal processing takes place inside the ballbar and data is transmitted to the personal computer via a wireless connection. The acquired data is used to calculate the overall performance of the positioning accuracy (roundness and roundness deviation) in accordance with international standards and Renishaw's own analytical reporting standards.
The ballbar data is displayed in both graphical and digital form to further assist in the diagnosis of machine tool errors. The ballbar assembly consists of 50 mm, 150 mm and 300 mm extension rods for the diagnosis of CNC machines of all sizes.
challenge
Regardless of the type, specifications, workload and usage of the machine, even if it is not the best maintenance, even the best CNC machine tools, the positioning accuracy may gradually decrease over time, resulting in machining errors. Component wear, damage from collisions, installation errors, and even changes in susceptor vibration and ambient temperature can adversely affect accuracy.
A Typhoon fighter of the 11th Air Force Squadron is ready to take off at the Akrotiri Airport in Cyprus at dawn (Photo courtesy of BAE Systems)
It is very expensive to find machine problems after the parts have been machined. A large proportion of the fuselage components manufactured by BAE Systems are made from titanium alloy materials. This high-strength, lightweight, high-temperature and corrosion-resistant metal material is expensive and increasingly scarce, and it is necessary to make a reservation to the supplier one year in advance to secure supply.
In addition to the losses caused by the scrapping of expensive materials, the machining time loss of CNC machine tools caused by machine tool errors is even more difficult to recover.
A complex titanium alloy fuselage assembly typically requires 40 hours of machine tooling. Repeated production of scrapped components can have a serious impact on the productivity of the company.
A typical example is that BAE Systems' manufacturing engineers have found that the machining accuracy of one machine in many machines is slowly declining, and shop floor operators are losing confidence in their performance. As it becomes more and more difficult to produce the parts that meet the standards, the problem machine is gradually being idle, and the workload it originally assumed is diverted to other machine tools.
To solve these problems, it is necessary to regularly check the performance of CNC machines. Maintaining the positioning accuracy of the machine is critical to ensuring quality and productivity.
solution
To assist in the periodic diagnostics of CNC machine tools, BAE Systems previously used Renishaw's QC10 ballbar system to identify specific machine performance errors.
Renishaw QC20-W wireless ballbar for machine tool performance diagnosis
BAE Systems is now using the second-generation QC20-W wireless ballbar, and has launched a preventive maintenance program covering the entire plant, requiring regular inspections of more than 60 CNC machines on a weekly, monthly and yearly basis. .
By analyzing the QC20-W diagnostic data trends for all machines in detail, BAE Systems has developed a reliable error range benchmark to quickly check the performance of all machine tools and allow operators to make "continue/non-continue" use of the machine. decision. Once the CNC machine tool positioning accuracy has any roundness error greater than 30 μm, it is necessary to investigate immediately.
Machine operators trained in ballbars can use the QC20-W to run diagnostic tests efficiently, which means they can be completed with production gaps, with little impact on production.
At the same time, BAE Systems also determined the optimal number of ballbar test components and CNC machine tools. The ratio is 1:15, which means that at some point, a billiard bar can leave the factory to go to a professional organization for annual calibration checks, while other ballbars can perform performance checks on different machines in the shop at the same time.
With the knowledge and experience gained with the QC20-W ballbar on different types of machine tools, BAE Systems is now able to delve deeper into the problem machine described above that has actually exited the production sequence.
BAE Systems observed a 200 μm XY roundness error using a ballbar. They used the ballbar diagnostic software to determine that the main failure mode of the machine was caused by servo mismatch, and then the second source of error was a large backlash error. The BAE Systems maintenance engineer corrected the servo mismatch by optimizing the X-axis drive parameters, and then they used the ballbar to re-examine the measurements to quantify the improvements.
However, the results of the re-examination showed that even if the servo mismatch had been eliminated, the machine still had serious errors. The engineers then checked and measured with the ballbar and the conventional gauge, and found that the error was due to the X-axis ball screw wear. Caused. After renovating the ball screw and resetting the backlash compensation value, the machine reached the 30 μm XY roundness requirement and rejoined the production sequence.
Jim Walsh, BAE Systems' professional manufacturing engineer, commented: “Making club inspections an integral part of machine condition inspections not only helps ensure consistent part quality, but also for machines that were once considered to be incompetent. The ballbar can also help us rejuvenate."
He continued: "The diagnostic software using the ballbar can automatically analyze the results and diagnose the errors, which means that the machine operator no longer has to calculate the true meaning of the data, determine where the problem occurs, and find remedies based on the principles and formulas. Measures. This will save a lot of time in actual production."
result
BAE Systems faces many challenges in processing high-value aircraft fuselage components, and incorporating the QC20-W wireless ballbar system into a dedicated CNC machine preventive maintenance program is a useful step in meeting these challenges.
Renishaw is also constantly updating the functionality of the ballbar diagnostic software. With the help of the new software, BAE Systems' innovative maintenance program to reduce material waste and increase productivity will add new vitality. In the germination stage, the root cause of the machine tool error can be found, and it is not necessary to be caught off guard when the problem actually occurs.
In the past, long and costly machine inspections and repairs have resulted in a large number of machine downtimes that are difficult for companies to withstand; now, BAE Systems' machine error diagnosis is almost instantaneous, which reduces downtime. In addition, with the aid of the ballbar diagnostic data, companies no longer rely solely on machine tool builders' services and support to solve related problems.
Thanks to the diagnosis of the Renishaw ballbar, a faulty CNC machine tool has regained its vitality, and significant progress has been made in workshop productivity and quality compliance, which has benefited BAE Systems.
About Renishaw
Renishaw is one of the world's leading engineering and technology companies with expertise in precision measurement and healthcare. The company supplies products and services to a wide range of industries and sectors – from aircraft engines and wind turbine generators to dental and brain surgery medical devices. In addition, it is a leader in global additive manufacturing (also known as 3D printing) and is the only company in the UK to design and manufacture industrial additive manufacturing equipment ("printing" parts with metal powder).
The Renishaw Group currently has more than 70 branches in 35 countries and employs more than 4,000 people, of whom more than 2,700 work in the UK. Most of the company's R&D and manufacturing is carried out in the UK. In the 2016 fiscal year ending June 2016, Renishaw achieved sales of £436.6 million, 95% of which came from export business. The company's largest markets are China, the United States, Germany and Japan.
SINOFUJI's various
tapes, whether they are for filling, sealing, insulating, fireproofing (flame
retardant), waterproofing, etc., have been used in aerospace, petroleum
exploration, high-speed rail, military and other related fields. SINOFUJI products
are demonstrated as the technical industrialization platform in adhesives of
the Changchun Institute of Applied Chemistry (abbreviated as CIAC, one affiliated
organization of CAS that is Chinese Academy of Sciences who was established in Nov.
of 1949 as the highest academic institution in China), and inherit the
technical accumulation of CIAC in adhesives and electrical insulation. CIAC, as
the shareholder of CASAC, has being cooperated closely with CASAC in the
high-tech industry. CASAC has a number of national patents and is a national
high-tech enterprise with intellectual property rights. As the parent company
of SINOFUJI, CASAC has many honors in the field of electrical power insulation:
l Provided products for the State Grid in 2008
to ensure the smooth progress of the Beijing Olympic Games.
l Provided products and services to China
Southern Power Grid in 2010 to ensure the smooth progress of the Guangzhou
Asian Games.
l Provided core technology and products for
power cable accessories (electrical stress control) to enable customer pass the
KEMA testing thus their products to serve the global market.
l Excellent supplier and long-term partner of
Aviation Industry Corporation of China.
l Occupies more than 50% of insulation
protection field of overhead contact line for China High Speed Rail Market.
It is confident to
say that customized design with highest cost effective is our strength serving
to all countries.
Power and Electric Tapes
Heat Resistant Tape,Waterproof Tape,Insulation Tape,Sealing Tape
ShenZhen FUJI Electric Material Co., Ltd , https://www.sinofuji.com
