1. Introduction
With the development in every field, various devices are also replaced by modern tools and machines. These modern devices are more efficient and secure. Magnetic chucks are a trending modern device that is widely used in industries.
Magnetic chucks are workpiece-holding machines that use magnetic force to secure the workpiece.
Let's discuss magnetic chuck and how it works in detail.
2. Getting To Know The Magnetic Chuck?
Magnetic has multiple alternative names, such as mag chuck, magnet chuck, magnetic beds, and magnetic tables.
A magnetic chuck is a work-holding machinery that utilizes magnetic force power from the permanent magnets to secure and clamp different work parts in position.
Magnetic chuck is a powerful tool that boosts productivity when cutting, grinding, or milling ferrous metals. It has replaced the clamps, mechanical vices, jigs, and fixtures.
The clamping pressure the magnetic chuck provides is enough to hold the workpiece properly. Magnetic chuck can hold workpieces of various sizes, from small to large-scale industrial parts.
3. Details On Different Parts Of Magnetic Chuck
Magnetic chuck consists of several parts that make it functional. These parts are:
● Lever
● Faceplate or top plate
● Aluminum casing
● Permanent magnets
3.1. Lever
Lever slowly moves the permanent magnets from crossways to line them up on the top plate with the conductive medium. This movement of the lever is named the on-and-off state of the magnetic chuck.
The eccentric clamp converts the lever's rotary motion into top plate sliding movement.
3.2. Face Plate Or Top Plate
The faceplate of the magnetic chuck consists of insulators and magnetic conductors. These are set out in the same manner as the permanent magnets arranged in the casing.
Moreover, the non-conducting and flux-conducting materials are arranged alternatively in the top plate of the magnetic chuck. This resembles the permanent magnet laid out in the chuck casing.
The entrance of oil or coolant inside the casing is prevented by the face plate as the face plate firmly closes in the magnets.
3.3. Aluminum Casing
The aluminum casing surrounds the magnetic chuck's permanent magnets, lever mechanism, and top plate. This aluminum casing performs the function of engaging and disengaging the chuck clamping power.
3.4. Permanent Magnets
Another important part of a magnetic chuck is the permanent magnet. Magnets in the magnetic chuck are arranged parallel, concentric, or radial in an aluminum carrier or casing.
4. Working Mechanism Of The Magnetic Chuck
Magnetic chuck uses magnetic force to keep a workpiece in the right position while work is done. The magnets of the magnetic chuck function by producing polarity into a ferrous work medium that connects across its south and north poles.
The flux flows in when the material to be held is positioned across the magnet poles. The poles of ferrous components are opposite to the magnets' polarity; therefore, they attract each other. Controlling and amplifying this flux is important in order to apply the magnets in the metalworking process.
The key is manually turned on to off to activate a magnetic chuck. Although magnets are always active inside the chuck, its magnetic flux is locked when it is turned off.
When the chuck is turned on, the magnets inside the magnetic chuck are attached to the top plate, where the magnetic flux moves above the face plate. And when a workpiece is put at the top plate, it gets secured because the flux is locked onto the face plate. As a result, the user can work securely on the workpiece.
Let's discuss in steps the working of a magnetic chuck.
Electromagnets Positioning
There are several electromagnets placed on the below surface of the magnetic chuck. These electromagnets are made of coils that surround a ferromagnetic core.
Creating Magnetic Field
Electric current is passed to activate magnetic chuck, which creates a magnetic field around every electromagnet. The magnetic field is upward toward the magnetic chuck work surface.
Temporarily Magnetizing Ferromagnetic Material
Only workpieces made of ferromagnetic material, such as steel or iron, can be placed over the magnetic chuck. When this ferromagnetic material is placed over the surface of the magnetic chuck, it becomes temporarily magnetized. This happens because of the magnetic field of electromagnets.
Magnets Force Of Attraction
When the ferromagnetic workpiece magnetizes, the surface of the magnetic chuck attracts it toward itself. The magnetic field holds the workpiece firmly on the magnetic chuck.
Releasing Workpiece From Magnetic Chuck
Once the work is done, the workpiece is released from the magnetic chuck. This is done by turning off the electric current flowing in the magnetic chuck. As a result, the electromagnets demagnetize and lose magnetic attraction because the magnetic field ends. Thus workpiece can be easily removed from the magnetic chuck.
Although you can use the magnetic chuck this way, it is crucial to use it carefully while following the safety guidelines. And remember that only ferromagnetic materials can be placed over the magnetic chuck, so avoid placing any other material over it.
5. Types Of Magnetic Chuck
Magnetic chucks are of three types based on magnet characteristics. These types are;
● Permanent magnetic chuck
● Electromagnetic chuck
● Electro-permanent magnetic chuck
5.1. Permanent Magnetic Chucks
Permanent magnetic chucks have permanent poles that constantly attract the part.
A permanent magnetic chuck is a type of magnetic chuck which consists of a magnet that possesses opposite poles and is placed over the top plate and cashing.
These chucks don't require any electric supply and are easy to operate. There is no risk of damage and wear because the construction design thus doesn't require repeated maintenance. Furthermore, a permanent magnetic chuck can be installed easily. But this magnetic chuck can not hold heavy workpieces because it cannot control holding force intensity.
5.2. Electromagnetic Chucks
This electromagnetic chuck gets connected only when the electric current is on. This type of magnetic chuck can turn off the magnetic pull resulting in the easy and quick release of metal parts. However, the metal part can only be released when the electric current is turned off.
If the power failure occurs during working, it can result in the de-clamping of parts and cause accidents.
The internal core gets magnetized when direct current passes across the coil; thus, a magnetic field is created.
Electromagnetic chucks are more powerful as compared to permanent magnetic chucks. This type of magnetic chuck can hold the parts with irregular shapes firmly.
5.3. Electro-Permanent Magnetic Chucks
This is a hybrid of electromagnetic and permanent types. Electro permanent magnetic chuck needs an electricity jolt to lock the part and then uses another electricity jolt to unlock it. If there is a power outage, the chuck will not lose the part and will continue to hold firmly while working apart.
In this type of magnetic chuck, each magnet is surrounded by an electrical coil, which can rapidly reverse the magnet's polarity. The coil also performs the function of controlling the magnetic pull that is exerted by the magnetic chuck.
6. Purpose Of Magnetic Chuck
The magnetic chucks hold ferrous metals because they are designed to enable the chuck to hold the ferro metallic workpieces. The mag chuck saves time by decreasing the time required for setting up the machine, decreasing the damage to metal parts, and lessening the setup process.
Magnetic chucks are a great tool for work holding in milling, surface grinding, and other CNC machining processes.
7. Applications Of Magnetic Chuck
Following are the applications of magnetic chucks.
7.1. Magnetic Chuck For Grinding
A magnetic chuck for grinding is a device for work holding used in surface grinding operations to hold the ferromagnetic workpieces in position securely and firmly. It is commonly used in precision grinding processes where parallelism, flatness, and high surface finish are important.
Electromagnetic Chuck For Grinding Machine can also be used for grinding purposes.
Primarily magnetic chuck for grinding offers the following advantages to the users.
● The magnetic chuck for grinding ensures a strong grip through its magnetic force and prevents its movement during the grinding process.
● This magnetic chuck can hold workpieces of different shapes and sizes, thus making it suitable for multiple grinding applications.
● The workpieces can be easily and quickly positioned over the magnetic chuck, thus saving time and enhancing the grinding process efficiency.
7.2. Magnetic Chucks For Milling
Magnetic chuck for milling, such as Permanent Magnetic Chucks For Milling Machine Chuck, is another great application of magnetic chucks, which are work-holding tools used in milling operations to firmly hold the ferromagnetic parts in position. Like magnetic chucks for grinding, the magnetic chuck for milling utilizes the magnetism principle to offer an efficient and reliable method of clamping the parts during the milling process.
It offers the following advantages.
● The magnetic chuck has a magnetic force that ensures that the workpiece is tightly clamped to the magnetic chuck, thus offering stability during the milling operations and preventing movement.
● The workpiece can be easily set up on the magnetic chuck, thus increasing productivity.
7.3. Magnetic Lathe Chuck
A magnetic lathe chuck is a popular device used for holding workpieces of large diameters and short lengths for machining. For increasing the magnetism force to the workpiece, additional chuck blocks are added for more consistent and accurate machining.
Magnetic lathe chuck consists of circular electro-permanent magnets which use distinctive variable cross-section magnetic pole structural design. With the increase in the outer diameter, the gripping power boosts gradually.
Furthermore, the Magnetic lathe chuck offers the following advantages.
● This magnetic chuck saves energy by 95% as it needs electricity for only MAG and DEMAG phases.
● Even if the power gets off, the workpiece will stay in its position.
8. Shapes Of Magnetic Chuck
Magnetic chucks come in various shapes, such as circular, square, and rectangular magnetic chucks. Each has its specific function.
8.1. Rectangular Magnetic Chuck
This type of magnetic chuck has a rectangular, flat shape and is mostly used in multiple metal working operations such as grinding, milling, and electrical discharge machining.
These magnetic chucks, such as General Rectangular Electro-Magnetic Chuck, have a longer life span and have high accuracy, thus clamping accurately for machining and grinding components.
8.2. Circular Or Round Magnetic Chuck
Round chucks are used in processes where the workpieces must be rotated. Mostly these chucks are utilized on lathe machines.
While working with circular or cylindrical workpieces such as discs, shafts, and other rotational symmetric elements, circular magnetic chucks are perfect options.
Circular Lifting Electromagnets for Steel Scraps perfectly hold the workpieces that have a round shape.
8.3. Square Magnetic Chuck
The square magnetic chuck resembles the rectangular magnetic chuck. It has a square, flat top surface with magnetic poles. This magnetic chuck firmly holds various cubic or square workpieces during machining.
9. Electromagnetic Table
The electromagnetic table is an effective and efficient device that secures the metal workpiece in any machining operation. This device utilizes the Lorentz or electromagnetic force to keep the workpiece in its place firmly.
Many cells with a core surrounded by a conductor coil are inside the electromagnetic table, where the core is composed of ferromagnetic material. The core changes into a magnet as the electric current moves through the coil. The cells inside the electromagnetic table enable it to hold the workpieces in position by producing a strong force of attraction.
10. Magnetic Grinding Table
A magnetic grinding table is another important device that is an important grinding machine accessory. It is fixed on the grinding table and lets you fix and release the workpieces easily and quickly.
Magnetic grinding tables have high precision, which means that the uniform force of magnets adsorbs the part on a flat surface without any fear of deformation.
The clamping force of the magnetic grinding table is uniform and high, thus preventing the workpieces from getting loose.
It resembles the magnetic chuck and firmly holds the workpiece while grinding.
11. Key Differences Between Magnetic Chuck, Electromagnetic Table, And Magnetic Grinding Table
Magnetic Chuck | Electromagnetic Table | Magnetic Grinding Table |
Workholding tool used in grinding, milling, and machining processes. | The specific type of work-holding device uses only an electromagnet during the machining process. | A special type of magnetic chuck is used specifically for surface grinding. |
The electromagnet or permanent magnet creates a magnetic field. | An electric power supply is required to activate and deactivate electromagnetic tables. | Either electromagnetic or permanent magnet depends on the applications |
Strongly holds the workpiece through magnetic attraction | Offers more convenience and flexibility by allowing quick setups. | Offers a stable and precise platform for getting the surface finish and flatness requirements. |
12. Frequently Asked Questions
12.1. What is a magnetic chuck?
Magnetic chucks are the latest devices that replace fixtures, vices, and mechanical clamps. Permanent, electromagnetic, and electro-permanent magnetic chucks can be utilized to clamp and unclamp the machine's components quickly.
12.2. How strong is a magnetic chuck?
The magnetic chuck force varies from type to type. It can be as strong as up to 16 kg per centimeter square. The strength of the magnetic chuck remains the same and doesn't reduce with time.
12.3. What creates the magnetic field in an electromagnetic chuck?
When direct electrical current is passed in the coils of electromagnetic chucks, a magnetic field is created. A control unit activates the electromagnetic chucks by quickly magnetizing and demagnetizing the workpiece.
13. The Final Verdict
This article explained magnetic chucks, electromagnetic tables, and magnetic grinding tables. Magnetic chucks are of different shapes, types and have various applications.
Magnet chuck is a powerful tool that boosts productivity when cutting, grinding, or milling ferrous metals. It has replaced the clamps, mechanical vices, jigs, and fixtures.
Magnetic chuck saves time and offers a secure operating method while firmly holding the workpiece.