62
Instruction and maintenance manual
ENGLISH
8
ORDINARY USE OF
THE SYSTEM
The following section describes the basic operating
procedure to follow in order to use the magnetic
chuck.
8.1 Clamping force
The clamping force of the system is directly propor-
tional to the working magnetic surface, the type of
material being machined and the general conditions
of the surface.
• Material to machine (mild and alloyed metal, cast
iron......)
• Superficial conditions of the part (roughness, line-
arity........)
• Contact surface between the part and chuck (i.e.
the surface in contact with the poles)
CLAMPING FORCE
PART TO
MACHINE
MAGNETIC CHUCK
The clamping force is distributed consistently.
The magnetic clamping force is always applied
towards the surface of the magnetic chuck.
8.2 Cutting force
The cutting force during all types of machining op-
erations always depends on the operating condi-
tions of the tool (depth, direction of movement, revo-
lutions per minute) and on the hardness of the
material that has to be machined.
The cutting force applied by a tool includes a
component that tends to slide the part being ma-
chined along the surface of the magnetic chuck.
PART TO
MACHINE
MAGNETIC CHUCK
Width
Depth
The horizontal component is influenced by the ge-
ometry and direction of movement of the tool. There-
fore, the clamping force must necessarily be greater
than the cutting force, which is distributed in all di-
rections, in order to guarantee a safe clamping of the
part.
It is therefore very important to make sure that the
clamping force, applied in straight line as compared
to the magnetic chuck, is reduced by one fifth (1/5)
in order to be able to contrast the tangential force,
which tends to slide the part.
Tool
movement
CUTTING FORCE
(direction of movement)
Example: cutting force of 1000 daN
Clamping force of 4000 daN
Clamping force = 4000 N/5 = 800 N
Therefore: clamping force of 800 daN <
Cutting force 1000 daN (resulting in an
insufficient clamping force)
If mechanical stops are installed to offset tangen-
tial forces and thus allow for the fact that the part
to be machined may slide on the magnetic contact
surface, changes in the forces in action can be ob-
served.
Clamping force of 4000 daN > Cutting force
of 1000 daN (resulting in a sufficient clamping
force)
