Technology drives die & mould industry

August 11, 2014 12:28 pm

Die and mould industry in today’s era is getting prospered in many ways with the help of technology. This article talks about such important technology drivers
 Today India is considered as one of the fastest growing economies in the world and many foreign companies can be seen investing in Indian projects. No wonder that like many other sectors, die and mould sector is also putting all its efforts to support the precision industries with some advanced technologies and trying to provide the best solutions to meet the ever-increasing requirements.
Let us have a look at these effective technology drivers that are making an impact being a vital part in growth path of the industry.
Technology drivers CNCCNC technology is changing rapidly, and the changes are helping to improve the productivity of machine tools used in the mould industry.
“Faster central processing units (CPUs) are at the heart of many CNC changes,” says Vaibhav Aggarwal, MD, Expo Machine Tools Pvt. Ltd. “However, the improvements go beyond just faster processing, and the speed itself touches on many different CNC advances. With so much that has changed in recent years, it’s worthwhile to present a summary of the state of mould-making CNC technology today.
Linear motorsA machine is only as good as its controller and its motion control system, since it is directly responsible for the movement of the axes.  The linear motor drive system is found to be superior to a rotary motor with ball screw drive system. The linear motor drive system relies on direct feedback from a linear scale for positioning, reporting an exact position and not a theoretical position.
“The linear motors and ceramics have revolutionised the electric discharge machines (EDMs), the V-LINE system in injection moulding machines are all solutions we have developed for solving customers’ problems,” says Ken Takahashi, Managing Director, Sodick Technologies India Pvt. Ltd. “These products are now the source of the competitive strength. Our products find applications in automobile, aerospace, medical, electrical, electronic industries and many more.”
This technology has improved significantly in recent years in both performance and acceptance. Commenting on the trend Mr Aggarwal says, “Every IMTS sees more machining centres offered with linear motors, and to date, Fanuc has shipped more than 1,000 units. Some of the GE Fanuc’s advances have resulted in machine tool linear motors with a maximum force of 15,500 N and a maximum acceleration of 30 G. Other advances have led to smaller size, lighter weight and more efficient cooling.”
It is clear that all of these changes serve to enhance the benefits linear motors offer over rotary motors. These benefits include higher acc/dec rates, superior position control and higher stiffness, improved reliability and inherent dynamic braking.
“Sodick has accumulated a rich portfolio of knowledge and expertise in linear motors including the know-how for the design and production of linear motors, best suited for various types of machines,” believes Mr Takahashi.
Linear motor drive system is simple in mechanism and easy to assemble as well. Moreover, it generates power efficiently due to little energy loss. Some of the more advantages of linear motor drive system are as follows:• High speed and high acceleration control system• Fast response due to no delay of motion control• High accuracy and repeatability when coupled with linear glass scales• Direct drive – no couplings or belts, no back lash or lost motion• No vibration on axes, no sticks-slips• No maintenance and longer life.
Five-axisAs CNCs have become more powerful, CNC manufacturers have been able to add more five-axis features. Capabilities once found only in high-end controls are now available in mid-range products. Most of the features have to do with making five-axis machining easier to use for shops that have little five-axis experience.
Mr Aggarwal adds, “Nowadays five-axis machining is increasingly being applied to complex mould work. The technology can reduce the number of setups and/or machine tools required to produce a part, thereby minimising work-in-process inventory and reducing total manufacturing time.”
Today, accessible CNC technology can deliver all of these benefits to the five-axis machining process:• Eliminate the need for qualified tooling• Allow tool offsets to be set after the part program has been posted• Support ‘machine anywhere’ programming, so that posted programs are interchangeable from machine to machine• Improve surface finish• Support various machine configurations, so the program no longer has to account for the spindle pivots or the work piece pivots. This is now accounted for by parameters at the CNC.  
How does technology helpHaving the right machines, with the right technologies specifically suited for high speed, hard milling of complex dies and moulds enables low labour-cost.
“With new technology machines, tools rooms are able to reduce cycle times and lead-times, lower labour costs through unattended machining processes, gain more business by offering rapid prototyping, high- performance milling and no-polish EDM burning, all while reducing total operating costs,” says Mr Aggarwal.
With latest 3D CAD and CAM software, die-mould shops are able to process long, complex mould programs at extremely fast speeds while achieving levels of accuracy and finish previously unobtainable. Hence dependency up on highly skilled manpower and higher lead time has decreased thus decreasing the overall costs.
“Frequently a mould can be made in one continuous operation, eliminating multiple setups, manual handling and the need to move parts from machine to machine,” adds Mr Aggarwal. “Moreover, the superior finish speeds up overall production even more by eliminating hand polishing, the most time-consuming part of traditional mould making.”
Initiatives being takenBeing proactive, the current industry players are taking some promising initiatives to offer their solutions in order to meet the requirements in die and mould industry. It is useful to know the same.
Mr Aggarwal informs about the initiatives being taken by Expo Machine Tools in this regard. Some of which are:• Introduction of new technology in the machine shops• High end quality assurance  and quality control instruments• New machines from Japan, USA And Germany• Proper workshops training for the employees• Recruiting skilled employees with proper training.
Ceramics is a material indispensable for ultra-precision machining because of its extremely small thermal expansion coefficient. Further ceramic being highly resistant, completely isolates the work-piece and prevents any leakage current flowing from the body of the machine. Such work-piece isolation helps to detect optimum spark gap and maintain the servo voltage accurately even at the high frequency low current skim passes.
In fact, ceramics offer a wide range of advantages when compared with other materials such as steel or plastic. Ceramic is light and yet hard, stable and resistant to ageing, it doesn’t rust, has a high electrical resistance, and scarcely changes at all under the effects of heat as its coefficient of thermal expansion is one third that of cast iron. In other words, ceramics are ideal for EDM.
Sodick owns technologies for producing ceramic products that support high-precision positioning such as high-rigidity machine structural components, informed Mr Takahashi.
Sodick machines are considered to be light-weight and high-rigidity structure, thanks to their key components made of proprietary ceramic products (FINEXCERA series).  Further, in Sodick wire-cut EDM machines ceramic components are used in critical areas such as the upper and lower arms, base plate and pedestals. In Sodick die-sinker EDM work table and Z-axis quill are the major parts made from ceramic.
End noteDie and mould industry is being driven today by continuously evolving technology, which in turn is making the industry more efficient and promising through increased productivity.