In this time sensitive and competitive manufacturing world, nobody wants to hear that their machine tool has just experienced a crash. When a cutting tool unexpectedly collides with the workpiece, the resulting impact force is often tremendous. Such force can damage or completely destroy a cutting spindle, or even worse, the machine itself.
These unfortunate and unforeseen crashes are expensive and take time from which to recover. Shops can suffer days of machine down time and loss of revenue as they fall behind in their production schedules. Just one spindle crash, for instance, can easily accrue to over $30,000 in repairs in addition to production losses.
Adding to the risk of machine tool spindle crashes is today's shortage of skilled labor. In our current manufacturing world, finding the right person for the job has become a difficult, if not impossible task. Tool makers and machine operators with experience are few and far in between. Employers are being forced to settle for workers with little to no skills to alleviate labor needs, thus increasing the risk of an accident.
More critical than ever, shops must have a way to protect their machine tool investments. This is why GF Machining Solutions developed its Machine and Spindle Protection (MSP) system for the company's milling product line, Mikron MILL S. What differentiates the MSP from other similarly intended systems, is that it protects the machine and spindle regardless of the direction in which the collision occurs. It is better suited to react and protect during a real-world situation and not only in one direction or axis, as the Z-axis for example, in other types of equipment.
During operation, the MSP allows the machine spindle to deflect when the force acting on the cutting tool during a collision reaches a strength that would damage the spindle bearing in the event of another surge. With this deflection of the spindle, the machine axis drives have the distance required to initiate an automatic emergency braking system.
The deceleration distance depends on the speed of travel. With the MSP mode active, it will ensure machine braking without damage, regardless of direction. In many cases, a collision can occur during the initial tests of new CNC programs. When running a program for the first time, the GF Mikron MILL can utilize M-function M304 to activate the feature. It now restricts the rapid feed of the axes to a safe feed to effectively brake and prevent damage. Feeds of 12 m/min (472 in/min) in X, Y, Z and A to 2,250°/min. or C to 3,150°/min can be reached while in this mode. After the MSP has successfully run through the process, it can be disengaged with a M305 command, allowing the machine to run back up to maximum rapid feeds. This feedrate does not limit general machining operations because usual cutting feeds are slower in many materials.
The mechanical safety features of the GF's MSP system are always in place even when the feature is not active and when the machine runs faster than its 12 m/min. This alone can minimize the effect of a collision. The system does not wear and is maintenance-free.
If a collision does occur and MSP responds, its benefits continue to prove itself. The machine can now be recovered without major efforts or the need for service intervention. Afterwards, it is recommended to run a standard automatic calibration routine (which the programmer/operator can execute) to relocate the machine and the CNC program's starting location points.
An MSP-protected machine tool is back up and running to its original precision in roughly 10 minutes after a collision. "No other crash protection system in the industry can deliver such fast turnaround times. Other crash systems, once crashed have to be serviced and replaced themselves, which translates into substantial downtime and repair costs," said a company spokesperson.
"When investing in a machine tool, solutions such as these is another tool that will provide some peace of mind and even more so, insurance, for your everyday manufacturing business needs," said the spokesperson.
Authored by Dante Payva, Milling Product Manager, GF Machining Solutions
For more information contact:
GF Machining Solutions LLC
560 Bond St.
Lincolnshire, IL 60069-4224
847-913-5300
www.gfms.com/us