Wilton FK350-4 사용자 설명서

15

When using the FK350 cold saw, it is important 
to select the correct type of blade for the 
material to be cut. This section explains the 
limitations and specific applications of the 
different types of blades. 

Fine Tooth Pitch --used for thin wall materials 
such as sheet steel, tubes and profiles 

Coarse Tooth Pitch --used for large cross-
sections -- for soft materials (aluminum alloys 
and soft alloys in general). 

Proper tooth pitch depends on: 

a) the size of the section; 

b) the hardness of the material; 

c) wall thickness. 

Solid sections call for 
discs with a coarse 
tooth pitch, while 
small cross-sections 
require blades with 
finer teeth. This is 
because when cutting 
walls of small cross-
section (1–7 mm) 
profiles, it is important that the number of teeth 
actually making the cut should not be too small, 
otherwise the effect obtained will be one of 
tearing rather than of chip removal, leading to a 
large increase in shearing stress. On the other 
hand, when cutting thick materials or solid 
sections using an excessively fine tooth pitch, 
the chip collects as a spiral inside the gullet, and 
since fine tooth pitches have small gullets, the 
accumulated chip will exceed the gullet capacity 
and press against the walls of the workpieces, 
resulting in poor cutting (same situation with soft 
materials), greater shearing stress and hence 
breakage of the blade. 

A larger pitch should be chosen when, as a 
result of the shape of the piece to be cut, the 
cross-section at any given point exceeds the 
average cross-section given above. 

The cutting speed, in m/min, and the head 
feeding speed, in cm

2

/min, are limited by the 

amount of heat generated near to the points of 
the teeth. If the head feeding speed is too high, 
the cut will not be straight in either the vertical or 
the horizontal plane. As we have already said, 
the cutting speed depends on the strength 
(kg/mm

2

) and hardness (HRC) of the material 

and the dimensions of the thickest section. The 
feeding speed depends on the cross-section of 
the material. Solid or thick-walled materials 
(thickness>5mm) can therefore be cut at high 
speed providing there is sufficient swarf removal 
by the blade, while thin-walled materials such as 
tubes or thin profiles must be cut with a low 
feeding speed. 

The cooling fluid ensures that the blade teeth 
and material in the area of the cut do not 
overheat. The fluid must be an excellent 
lubricant so as to prevent abrasion of the teeth 
and welding of the chips to the teeth themselves 
(seizing).