Is it Time for Plastics Manufacturers to Invest in 6-axis Robots?

The versatility of multi-axis robots and the many processes in the plastics sector that are within their capabilities for a wide range of common tasks in the plastics sector, from high speed demolding right through to inspection and assembly.

The economic benefits of automation by using industrial robots have never been clearer. While labor rates continue to rise and availability of skills provides ongoing difficulties, the actual cost of robots has been decreasing. Price decreases approaching 25% have taken place since 1993. An investment decision for an industrial robot can now often be of a value similar to that for a company car.
 
This price reduction alone has opened many potential applications to industrial robots that historically would have been difficult to justify. There has never been a better time for manufacturers to invest in robotics. Payback times of 18 months and less are achievable through increased productivity and reduced wastage of materials, in addition to the benefits on operator safety, which are realized immediately.

Manufacturers in the plastics sector are increasingly incorporating 6-axes robots into their production facilities in response to customer demands for shorter lead times. The integration of automation also brings the flexibility to adjust production volumes and change product types quickly to match rapidly varying levels of demand.

This is particularly relevant in the supply of plastic components to the electronics and telecommunications sectors where new models rarely last for more than six months and production volumes can easily double, treble or halve during this short period. Flexible, responsive production becomes a necessity.

Manufacturers and system integrators are discovering that multi-axis robots provide a consistent and practical solution to all of the automation applications in the plastics sector. Many 6-axes robots are particularly suited to these tasks, with current installations providing excellent results in the plastics sector on:

• Demolding
• De-sprueing
• In mould decoration
• Glue laying
• Powder coating
• Painting
• Assembly
• Inspection
• Packaging 

Many users have found that being able to standardise on certain robots for the automation of all these types of operations right across a number of production facilities is an attractive proposition. It minimizes training costs, simplifies integration and reduces the cost of spares and servicing; but, more importantly, the resulting increased familiarisation with the robot's features and capabilities ensures optimum solutions are achieved.

Today's robots are ideal for these accurate and meticulous types of task. They feature high speed and acceleration and are capable of following complex trajectories. Users benefit from outstanding joint speed and consistent performance. Load capacities vary by manufacturer, and reach is another variable, however in all cases the movement in six axes provides an extremely large work envelope.

Speed of operation is often the prime concern when selecting the type of robot. It is commonly accepted that simple Cartesian 2- or 3-axes robots provide the fastest operation on, for example, demolding components from injection molding presses. Consider, however, that some manufacturers would counter this axiom with products capable of high speed demolding giving die interrupt times down to just 0.59secs.  Among the leading models, accuracy and inherent rigidity of the robot construction are major advantages, eliminating unnecessary movement of the extraction tool on the robot arm and positioning the tool precisely where needed.

More than 115,000 robots are installed in North America, and many end users are realizing the benefits that flow from a comprehensive understanding and appreciation of the wide-ranging capabilities of these highly developed machines. Leading robot suppliers are working to ensure that the changing demands of the marketplace will continue to be fully reflected in their robot model ranges and capabilities.

Recommended Resources/Reading

• David Arceneaux, Staubli, [email protected]
• Bob Turner, Quadcom Ltd., [email protected]
• Consumer Products Produced by Robotics. . . . by Bennett Brumson
• Vertical Injection Molding Industry Turns to Robotics. . . . by Jay Hallberg
• Robots Improve Productivity at Glasland Industries
• Staubli Robots Provide the Ideal Solution for Injection Moulding Specialist