Machining gray cast iron CBN insert for
CNC Lathe
Part 1
The characters of gray cast iron
(1) Poor strength;
(2) Hardness: a range in tensile strength.
(3)Low notch sensitivity;
(4) Good reduction shock;
(5) Good anti-friction properties.
As its low cost, the production process is
simple, so it also was widely used in auto parts, such as brakes,
brake drums, flywheels. Some gray cast iron parts belong consumables,
manufacturers will have large demands. Improving the processing efficiency and the costs
become very important. So it is very important to choose the most
suitable inserts material to machine the gray cast iron parts.
Part 2 How to choose inserts
machining gray cast iron for CNC Lathe
Currently, there are 3 kinds cutting
tools can be used for machining gray cast iron for CNC Lathe:carbide insert, ceramic insert and CBN
insert.
(1) Carbide insert: Carbide insert
was sensitive to the linear velocity.when machining gray cast iron
with high speed, the tools lifetime will be low, which
will result a higher frequency for change the insert,
and ultimately affect the
processing efficiency and increase the insert costs (choose carbide tools for small quantities machine the gray cast ironwaseconomical choice).
processing efficiency and increase the insert costs (choose carbide tools for small quantities machine the gray cast ironwaseconomical choice).
(2) Ceramic insert: the hardness of ceramic insert is higher than
carbide insert, but as its brittle, white tissue easily chipping when
meet hard spots,It is well for ceramic tools for finish machining or large
allowance process.
(3) CBN insert : CBN insert
has a higherhardness than carbide insert and ceramic
insert, traditional CBN insert has bugs in brittleness.
But Non-metallic binder BN-S30 CBN insert has a better toughness,
higher hardness, better wear resistance, strong impact toughness,
and can ensure part accuracy requirements while enabling high-speed cutting,can machine the parts when meet hard spots and white tissue without annealing directly.
The Cutting parameters of CBN insert machining gray cast iron
The Cutting parameters of CBN insert machining gray cast iron
The material of machined parts
|
CBN inserts cutting parameters and grade
|
|||
Cutting speed（m/min）
|
Cut depth
(mm)
|
Feed rate
（mm/r)
|
Insert grade
|
|
Gray cast iron
|
200-500(rough machining)
|
1-10
|
0.2-1
|
BN-S30
|
500~1500（finish machining）
|
≤1
|
0.05-0.3
|
BN-S30,BN-K20 or BN-S300
|
|
The characteristic of BN-S30 grade CBN insert
(1) High hardness;
(2) Better impact toughness and wear resistance
(3) High-speed cutting.
(4) Both roughing and finishing,
Dry cutting and Wet Cutting
BN-K20 and BN-S300 also
can be used for finish machining gray cast iron.
BN-K20 CBN insert belongs to welded CBN insert, its advantage is more flexible,
more cutting edge number; excellent wear resistance;
more cutting edge number; excellent wear resistance;
BN-S300 CBN insert belongs to the Solid CBN insert,
advantages as follows: excellent sharp type, suit for gray cast iron work
pieces finishing and semi-finishing.
Rough and finish machining Cylindrical and end face on CNC lathe
as the out diameter was different (300-419mm),the cutting time was different
One Japan carbide coated inserts: Depth of cut ap = 2.5mm (roughing),
ap = 0.3mm (finishing), line speed 270-330m/min;
roughing and finishing spend respectively 5 minutes and 4.5 minutes.
Non-metallic binder BN-S30 CBN insert: Depth of cut ap = 2.5mm (roughing), ap=0.3mm (finishing),
linear speed 650-720m/min;spend separately 1.5 minutes and 75 seconds.
roughing and finishing spend respectively 5 minutes and 4.5 minutes.
Non-metallic binder BN-S30 CBN insert: Depth of cut ap = 2.5mm (roughing), ap=0.3mm (finishing),
linear speed 650-720m/min;spend separately 1.5 minutes and 75 seconds.
Part 4 Summary
With the development of the
technology ,manufacturers will required more on the insert lifetime and the
product quality. They would like to improve the processing efficiency and
obtain the excellent performance. And it also a big chance for insert
manufacturers. Halnn is a professional manufacturer of cbn insert and always
devote to researching new cbn insert materials to satisfy the customers’
requirements.And Halnn already become the most famous cbn insert brand in China
.
Any question on cbn insert or hard
materials machining,please contact with us
halnntools@gmail.com.skype:cbn_inserts_angels
