The spray painting division of Hilustre Coatings handles a wide and varied range of products, ranging through kitchen cabinets, display panels, shop fittings and automotive components. One of the more unusual products they paint is plastic panels for life-size animatronic dinosaurs for a theatrical production. The materials range from timber, metal, plastic and glass, adding to the need for flexibility of the spray-painting operation, involving relatively small volumes of a particular product.
Difficulty in finding skilled staff
Initially, the idea to consider robotics was prompted by looking at the mechanised operations at its powder-coating division, and thinking that the spray-painting operation could benefit from more efficient ways of operating its business, says Peter Harrison, the General Manager of Hilustre Coatings. One other major consideration in looking at robotics was the increasingly difficult position of finding skilled staff, which impacted on operations.
“We looked at the possibility five years ago, visited a number of robotics trade shows and discussed the concepts with several robotics suppliers,” says Harrison. “However, the capital outlay and cost of the associated software programs to cater for our specialised requirements was prohibitive for a business of our size.
“When we looked at other systems I was sure the robot could paint with precision, but our main problem is the ever-changing variety of parts we have to paint each day. To program the robot through the Teach Pendant is time consuming, which is fine if you only have a few parts and high volumes, but being a job shop we are painting different-sized parts in every job. A kitchen may have 70 different-sized doors and panels, so we needed a system that could make the robot create its own spraying path by just entering the size of the parts.”
ABB partner designed flexible system
The breakthrough to make the acquisition of a robot a practical proposition came when Harrison met Glenn Westonsmith of Robotsplus, an integrator that works with ABB robots. Hilustre worked with Westonsmith to devise a flexible software program that suited its requirements. The custom-designed Windows-based program is connected to the robot controller via a standard computer. The key feature is its ease of use — no previous robotics experience is required for the operator.
The Windows-based program makes operation and adjustment of the system simple. Parts are entered into a job entry page which includes the size of the parts, how many edges are to be painted and even a section on the underside of the panel can be selected. Various 'paint patterns' can be chosen depending on the type of finish required. This determines the number of coats and all of the robot-spraying parameters such as fluid and air volumes, etc.
Once entered, the parts can be identified via a bar code scanner or keyboard entry and the optimising program determines the position of each part on the delivery table to maximise efficiency of the spray-painting process. This is displayed on a monitor in the loading chamber, giving the operator an accurate view of the positioning and shape of the article. Parts then travel into the separate spraying chamber and the robot paints them producing uniform quality with 100% consistency.
The installation of the robotic process allows Hilustre to train unskilled operators in a very short time, with excellent production results. Processing around one million items annually, the variation in size, shape and product diversity means the program must be capable of quick and easy transition to cope with the requirements of the facility.
Efficiency increased 40%
“We now run on an increased efficiency of some 40%, using one operator and having reduced the amount of paint per run while increasing the quality and consistency. Colour changes are done in minutes and waste less paint and solvent. All of which produces improved economy for our operations,” Harrison says.
Another advantage in installing the robotic spraying system is the improvement in health and safety for the operator, who is separated from the actual spraying operation and not exposed to the hazardous elements of some paints.
“The system was a collaboration with Glenn who programmed and commissioned the robot, Couray Sheetmetal who designed and built the spray booth, while we designed and built the pneumatic conveyor tables, and ABB who supplied the robot,” says Harrison.