APMEN: From a cutting tool maker’s perspective, what is the most pertinent trend in the aerospace industry which will cause the most impact in the metal cutting sector and why?
Reuven Shapir (RS): Demand to increase Productivity, Performance and Profitability (PPP) has resulted due to a need to apply new cutting tools and grades for machining tough and hard steels, high temperatures alloys, and titanium with reduced Cost Per Unit (CPU).
Modern CNC controls with the ability to work and control very fast feeds lead to using the High Speed Machining (HSM) method that uses tools with an increased maximum number of flutes.
It also results in milling with a small width of cut and short contact time during the cut. That contributes to reducing generated heat and increasing the cutting edge life when machining the tough materials that are very common in the aerospace industry.
The results of extreme table feeds to achieve high Metal Removal Rate (MRR) with the advantage of less generated heat due to small contact time enable the ability to achieve more PPP.
The increase of coolant efficiency by delivering the coolant directly to the cutting edge with a much higher pressure method, High-Pressure Coolant (HPC) enables the increase of cutting parameters and doubles the cutting speed, due to the more efficient cooling. That in turn contributes to reducing the generated heat in the cutting zone and increases PPP.
APMEN: Do you see the aerospace and defence sectors growing in Asia and how would it affect the metal cutting industry?
RS: All of the forecasts show that the demand for aerospace products will increase in large numbers for the long term because the demand for passenger flights is rising rapidly due to globalisation and international tourism, placing increasing demands on the aviation industry.
The international political tension all over the world contributes to increase in military budgets with more demands for aerospace and defence equipment.
The aerospace industry in Asia is growing quickly. They have the advantage of being sub-contractors with lower production costs versus production in western countries. In addition, there is an increase in demand for military aerospace products (for own consumption). These circumstances contribute to the rise of the aerospace industry in industrialised Asian countries.
APMEN: Do you see 3D printing as a competing or complementary technology for traditional cutting technologies in the field of aerospace?
RS: Due to the tough demands for strength and metallurgical features for parts in the aerospace industry, using parts produced by 3D printing technology is limited in the near future.
APMEN: What are the special characteristics that operators need to take note of while machining various airplane parts? Do you have any tips in terms of metal/composite materials cutting to help increase the productivity in manufacturing aircraft components?
RS: The aerospace industry is managed under the AS100 standard with very strict QA rules. One of the main rules is that after the FAI (First Article Inspection) is done, it is forbidden to create uncontrolled changes in the production process.
Actually the process and technology are sealed and any further change demands a complicated approval procedure. Therefore the demand in the aerospace industry is to produce parts which are 100 percent perfect from the beginning.
This requires the highest engineering and technology attention and focus in order to design the process right from the beginning of the production trials with the most suitable tool technology and CNC programs with the most efficient tool path.
In order to reach this goal, it is required to be very professional and updated with knowledge about the most innovative tools for each machining operation. Therefore engineers and technologists require close professional support from the tool manufacturers, with specific experience on the performance of their tools.
APMEN: What are some of the technological advancements in milling, turning and hole making that can be applied to the aerospace sector?
RS: The demand for better cost saving drives the need for an increased number of cutting edges per insert. Iscar’s standard double-sided inserts with double cutting edges are available as standard — rhombus, square, round, FF style (Fast Feed), hexagonal and octagonal (up to 16 cutting edges in one insert) — in all insert size ranges.
Milling aluminium parts with high spindle speed up to 33,000 rpm with high powerful spindle power above 100 kW and fast controls enable the increase of MRR for milling aluminium. Tools should be designed to perform at these extreme conditions. For example, the Helialu designated HSM90S line includes 90 deg milling cutters for milling aluminium at very high rotational spindle speeds.
