Electro Permanent Magnetic Chuck

Product Description

High Precision Electro Permanent Magnetic Chuck
Our high precision electro permanent magnetic chuck for sale at a bargain price, it is ideally suited for clamping of small and big work pieces for milling operations. Pole extensions, easily fixed on the surface of the magnetic chucks, guaranteed a clamping without distortion even for uneven work pieces. The full steel body, offers an ideal protection against external influences like hot chips and coolant. If you work very big work pieces, you will get optionally a 4 channel controller, making a simultaneous switching of max. 4 magnetic chucks.
                                    
Specification
 
 

Item No.	W (mm)	L (mm)	H (mm)	Poles
GME-EMC01	240	430	93	18
GME-EMC02	300	430	93	24
GME-EMC03	420	590	93	48
GME-EMC04	480	750	93	60
GME-EMC05	600	990	93	126
GME-EMC06	250	425	93	8
GME-EMC07	327	601	93	18
GME-EMC08	415	815	93	32
GME-EMC09	503	1029	93	50
GME-EMC10	591	601	93	36

 
Feature
• A magnetic bed which comes also with a T-Slots.
• The working surface of the electro permanent magnetic chuck is machined from a single block of mild steel, wherein the poles are demarcated by making slots in the top surface obviating the need to use filler material.
• Very rigid and robust construction.
• Universal clamping directly on Magnetic bed for both ferrous and non ferrous components.
•Maximum accuracy due to homogeneous surface.
•Once clamped on the precision machine table -assures 100% safety to the original machine bed.
•Pole size 50 x 50 mm
• Adhesive force ≥ 350 kg per pole
•Penetration depth of the magnetic field at maximum of adhesive force level up to 12 mm
•A minimum of 8 poles contact is necessary for optimum clamping
•Controller for the magnets above

Application
• This kind of electro permanent magnetic chuck could be clamp small or big workpieces by milling processes
•Clamping without vibration and distortion
• Manufacturing and process accuracy with plane parallelism of 0.02 mm and more

 How to choose a magnetic chuck?

1. Contact Area
The ideal condition is minimum air gap, which offers highest resistance to machining force and larger contact area. The poorest results are obtained where large airgaps and limited (line) contact.
 
2. Surface Finish
A lapped finish which has no air gaps present the best magnetic workholding condition, a coarse surface with many air gaps the worst.

c	Ground finish	Rough finish	Rough planned	As Cast
100%	85%	65%	45%	25%

3. Workpiece Materials
Maximum induction of flux is done in Pure Iron and minimum in Stainless Steel for practical purpose.
 

Cobalt Iron	Best possible grip  26 kg/cm^2
Mild Steel (C-<0.25%)	Best practical grip   17 kg/cm^2
Carbon Steel (0.9%)	Best possible grip   12 kg/cm^2
Cast Iron	Best possible grip     8 kg/cm^2
Nickel (SS 410/420)	Best possible grip     2 kg/cm^2

4. Condition of Material
Heat Treatment of materials effects its physical structure and its ability to absorb Magnetic Flux. Annealed materials absorbs Maximum induction of flux and do not retain any residual magnetism.
Hardened materials do not absorb as much Magnetic Flux but tend to retain after the Chuck is switched Off.
 
5. Workpiece Thickness
The Magnetic Flux path within a work-piece is a semi-circle path from the center of one Chuck Pole to the Center of the next Pole.
So if the work-piece is thinner than its radius path, it cannot absorb all the flux and some passes out in Air. Thus the resultant pull is lower than that when all the flux is absorbed by a Thick job.
 
Note: Different types of magnetic chucks For work holding
1. Permanent Magnetic Chuck
2. Electro Magnetic Chuck
3. Electro Permanent Magnetic Chuck
From the above it is found that the main consideration for choosing the correct type of Magnetic Chuck is determined by the above 5 factors.
Further type of Grinding Machine and the directional force of the Wheel is also to be considered. (direction on which the grinding or cutting force is applied).
Generally the maximum grip is generated where force is applied at right angle to the pole direction. Downward force is 4-5 times the magnitude of the sliding force so that the greater the downward grip the less likely is the job to slide.