Assessing The Security Of Magnetic Workholding

Izvor: KiWi

Inačica od 05:35, 10. ožujka 2014.

Resistance to the implementation of magnetic operate holding normally begins with a concern for safety. These issues could be allayed by assessing the technologies, holding energy and optimal operating circumstances of magnetic function holding with regards to operational safety.

Regardless of the competitive small cnc machines added benefits of magnetic workholding in lowering charges and enhancing productivity, there nevertheless exists a resistance to the implementation of magnetic technologies as the major work holder in machining operations. This resistance generally starts having a concern for security. By assessing the technology, holding energy and optimal operating situations of magnetic function holding relative to operational security, these issues can be allayed.

Magnetic Work Holding as a Protected Technologies

If a machine operator has held workpieces with mechanical clamps for decades, the idea of relying on magnetism to hold workpieces, specially in heavy milling operations, boils down to a problem of trust: Is this definitely protected? Whilst understandable this opinion is rooted in subjectivity not objective fact. More than probably, people who hold this point of view may not completely recognize the facts of how secure magnetic perform holding is.

So, how can magnetic perform holding be viewed as as a secure technology? By definition, it produces a uniform, constant, and infinite holding energy that does not loosen up, give, or decrease till an operator de-energizes it.

Normally, magnetic operate holders are constructed with an array of individual magnets embedded into a magnetic chuck or plate. Every single magnet has a north and south pole across which flows magnetic power referred to as flux. When a workpiece is placed across the poles of those magnets, flux flows into it. When placed within this flux field, a magnetic field of opposite polarity is induced into the workpiece thereby producing a magnetic attraction between the chuck and also the workpiece. This attraction will remain consistent, uniform, infinite, and reliable provided that the magnetic field is energized. This reliability makes magnetic workholding a really secure technology.

Magnetic Operate Holding as a Protected Holding Force

Holding power or strength is another factor deemed when forming an opinion in regards to the safety of magnetic workholding. If an operator doesn't know how sturdy magnetic workholding is, he may perhaps mistakenly believe magnetic technology is not strong adequate to do the job safely. This opinion could be allayed by two facts:

(1) magnetic workholding can possess a clamping energy up to 1000 daN and

(2) based upon the application, an instantaneous clamping force of 12 tons per square foot might be generated by magnetic workholders. This degree of holding force is greater than comparable to mechanical clamps with 1 more advantage: magnetic holding force is uniform, continuous and infinite till the operator de-energizes it.

Optimal Operating Circumstances

To implement magnetic work holding options may demand some training to understand the technology's optimal operating situations. As an example, magnetic work holding is most effective utilised with smooth-surfaced workpieces rather than rough ones for the reason that the smoothness decreases the air gap between the workpiece plus the magnet; little air gaps raise magnetic attraction and also the holding bond. Some materials are improved conductors of magnetism than other folks. For example, annealed supplies are excellent while hardened supplies never absorb flux as conveniently and will retain some magnetism. This condition is usually corrected within seconds with demagnetization. Finally, the path from the holding force is but a different adjustment an operator might have to make to safely implement magnetic perform holding. All magnets have 100 percent clamping force directly away from the face with the magnet, but only about 20 % clamping force against side forces. So, the geometry of a reduce should be considered inside the machining course of action to reap the positive aspects of this sort of workholding.