About stainless steel:
Stainless steel, simply referred to as SS, has several distinct characters, such as plasticity, work hardening, easy to accumulate shavings, which are always worsen processed surface.
Why difficult to drill?
1. Cutting force is 25% higher than 45# carbon steel (normalizing), with higher hardening level and in depth.
2. Lower thermal conductivity, 1/3 of 45# carbon steel, produces more heat and leads to higher cutting temperature.
3. Drill to fast or too slow, makes stainless steel work-hardened, makes even harder to drill through.
4. Due to high cutting temperature, work hardening, carbide existing forms foreign inclusion, drilling tools are easily to wear, have low durability.
Two aspects of processing difficulties:
SS has less machinability than carbon steel, the drilling of SS even worse than the lathe work of it. Therefore, drilling SS has the following 2 aspects:
1. High plasticity and tenacity bring adhesion abrasion to drilling tool. With low heat and thermal conductivity make hard to dissipate heat during drilling. Irrational geometric angle of drilling tool leads to high abrasion and low durability.
2. The banded chips are easy to hurt people and hard for drilling fluid injection. It’s necessary to change the geometric parameters, choose rational cutting output.
Some suggestions:
To enhance drilling tools durability, guarantee chip breaking and removal, it’s necessary to choose the right drill bit, hand pressure, drill speed, keep drilling tools cool. Apart from this, should change the geometric parameters, rational cutting output.
More info:
Jinan Supertime Technology Co.,Ltd
CNC machine design & manufacture specialist
Q:What factors influence CNC angle line gauge line or backmark?
A:Pressing device & V type surface.
When steel angle enters machine, before punching action, pressing jaw holds angle to C type surface, thus ensure backmark stability. Without saying, any problems with these 2 mechanisms will lead to backmark error.
As pic. above shows: Wear occurs when pressing jaw works long time, distance between pressing jaw and angle makes angle processing unstable, and causes backmark error.
This pic shows V type surface, wear also occurs after long term usage. Try to keep 90°A and B surfaces.
