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disadvantages of electromagnetic crane

          The working principle of the electric retarder is based on the electric retarder is based on the creation of eddy currents with in a metal discs rotating rotating between two electro magnets, which set up a force opposing the rotation of the discs. If the electromagnet is not energized, the rotation of the disc free and accelerates uniformly under the action of the weight to which its shaft is connected. When the electromagnet is energized, the rotation of the disc is retarded and the energy absorbed appears as heating of the discs. If the current exciting the electromagnet is varied by a rheostat, the raking force varies  indirect proportion of the value of the current. The development of this invention began when the French company Telma, associated with Raoul Sarazin, developed and marketed several generations of electric brake based on the functioning principle described above. A typical retarder consists of stator and rotor. The stator hold 16 induction coils, energized separately in group of four. The coils are made up of varnished aluminium wire mounted in epoxy resin. The stator assembly is supported resiliently through anti-vibration mountings on the chasis frame of the vehicle. The rotor is made up of two discs, which provide the braking force when subjected to the electromagnetic influence when the coil are excited. Care fully design of the fins, which are integral to the disc, permit independent cooling of the arrangement.

the energy requirements of braking at high speeds, completely without the use of friction. Due to its specific installation location (transmission line of rigid vehicles), electromagnetic brakes have better heat dissipation capability to avoid problems that friction brakes face times the braking power of an exhaust brake.

Lifting magnets are used to move and position ferromagnetic (often steel) work pieces of various shapes and lengths quickly and without damage. A lifting and hoisting magnet saves valuable storage space and time.

Joe Hall is the founder of Clarus Systems in San Clemente California. For the past 20 years, he has explored the effects of man-made electromagnetic field (EMF) radiation on human health and psychology, and has developed a family of devices to neutralize these negative effects and restore our own energy field to create healthier home, work and personal environments, and less stress and fatigue. Clarus Technology has been used by Bell Atlantic to reduce soft memory errors on stressed computer systems. Clarus Coherent Polarizing Field Effect "aligns" random charged particles (non-binary photons) associated with all EMF frequencies to produce an infinitely small trace of coherent binary photons.

How do these things work in practice? Suppose you have a high-speed factory machine that you want to stop without friction. You could mount a metal wheel on one end of the drive shaft and sit it between some electromagnets. Whenever you wanted to stop the machine, you'd just switch on the electromagnets to create eddy currents in the metal wheel that bring it quickly to a halt. Alternatively, you could mount the electromagnet coils on the rotating shaft and have them spin around or inside stationary pieces of metal.

Electromagnets employ electricity to charge the magnet and hold the material to the magnet face. Electromagnets use an energized electrical coil wrapped around a steel core to orient particles within ferrous materials in a common direction, thus creating a magnetic field. Electromagnets are generally built to run on DC current, creating the need for a rectifier. Unlike permanent magnets, electromagnets require a constant power source. This can be viewed as either a detriment or an advantage, depending upon how the magnet is being used. A power failure can be catastrophic when using an electromagnet?though universal power supplies and battery backup systems available in today's market address these concerns. On the other hand, the ability to vary the current being supplied to the magnet allows the user more flexibility than a permanent magnet affords.

You will be able to drastically improve the workflow that you take advantage of when you get your hands on an electromagnet overhead crane. Your work will by quicker and you will have less injuries on the jobsite. You also be able to keep your profit margins in line because it would take far less manpower to get the work done.

Both permanent magnets and electromagnets can be constructed to produce different types of magnetic fields. The first consideration in choosing a magnetic circuit is the job you want the magnet to do. Permanent magnets are favored when electricity is not readily available, when power failures are a common occurrence or when adjustable magnetic force is not necessary. Electromagnets are useful for applications where varying strength is required or remote controlling is desired. Magnets should be used only in the manner for which they were originally intended. Using the wrong type of magnet for a specific application can be extremely dangerous and possibly even deadly.

The electromagnet contains an iron core with a wire around it, and this wire is the medium by which the current travels. The magnetic strength of an electromagnet relies on the number of turns of the wire around the electromagnet's core, the current through the wire and the size of the iron core. Increasing these elements will result in an electormagnet which is significantly larger and stronger as compared to a natural magnet (which explains the enormous size of the crane's magnet). For the electromagnet to be turned off, the core must be made of soft iron. Therefore, turning on the electricity will enable the magnet to work, and turning off the electricity will be able to shut it down.

Electromagnets employ electricity to charge the magnet and hold the material to the magnet face. Electromagnets use an energized electrical coil wrapped around a steel core to orient particles within ferrous materials in a common direction, thus creating a magnetic field. Electromagnets are generally built to run on DC current, creating the need for a rectifier. Unlike permanent magnets, electromagnets require a constant power source. This can be viewed as either a detriment or an advantage, depending upon how the magnet is being used. A power failure can be catastrophic when using an electromagnet—though universal power supplies and battery backup systems available in today's market address these concerns. On the other hand, the ability to vary the current being supplied to the magnet allows the user more flexibility than a permanent magnet affords.

Both permanent magnets and electromagnets can be constructed to produce different types of magnetic fields. The first consideration in choosing a magnetic circuit is the job you want the magnet to do. Permanent magnets are favored when electricity is not readily available, when power failures are a common occurrence or when adjustable magnetic force is not necessary. Electromagnets are useful for applications where varying strength is required or remote controlling is desired. Magnets should be used only in the manner for which they were originally intended. Using the wrong type of magnet for a specific application can be extremely dangerous and possibly even deadly.

Still, there are times when the part to be machined is thin—0.25 inch or thinner—and the part is presented to the machine operator as one of a stack of similar parts. Permanent magnets are not designed to lift only one piece from the stack at a time. Permanent magnets, while extremely reliable when properly applied, are not able to alter the amount of magnetism produced. In this case, an electromagnet with variable voltage control allows the operator to manage the magnetic strength and select only one piece from the stack.

A trained professional must install the magnet. The supplier will usually send out personnel to evaluate the application and handle the installation process. Electromagnets require greater setup time and additional equipment because of the DC electrical connection. Electromagnets are also outfitted with battery backups in case of power failure.

The electromagnet contains an iron core with a wire around it, and this wire is the medium by which the current travels. The magnetic strength of an electromagnet relies on the number of turns of the wire around the electromagnet's core, the current through the wire and the size of the iron core. Increasing these elements will result in an electormagnet which is significantly larger and stronger as compared to a natural magnet (which explains the enormous size of the crane's magnet). For the electromagnet to be turned off, the core must be made of soft iron. Therefore, turning on the electricity will enable the magnet to work, and turning off the electricity will be able to shut it down.

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