Ultrasonic welding raises productivity

Citation

(1999), "Ultrasonic welding raises productivity", Assembly Automation, Vol. 19 No. 1. https://doi.org/10.1108/aa.1999.03319aaf.001

Ultrasonic welding raises productivity

Ultrasonic welding raises productivity

Keywords Ultrasonic, Welding

When Cole and Mason, the world's largest manufacturer of salt and pepper mills, decided to streamline its production lines it looked carefully at how its mills were put together. By investing in two ultrasonic welders to attach a plastic guard over the base of its acrylic salt and pepper mills (see Plate 1), Cole and Mason has increased productivity and managed to cut costs.

"Previously, the plastic guard was attached with screws by hand and the half-assembled mills then stored until they could be taken for full assembly", explained Brian Buckland, industrial engineer. "The mills are now fully assembled, filled and packaged along one line."

It is not just the streamlining of the production lines that has helped improve productivity, the assembly process itself is now much quicker with the welding only taking 0.25 seconds per mill. "Ultrasonic welding has proved to be much faster than having the plastic fitting screwed on by hand", Brian commented. "We can now increase our output by avoiding the problems associated with screw fixing and in the long run improve quality and save money. We expect the machines to pay for themselves in about a year."

Plate 1By investing in two ultrasonic welders to attach a plastic guard over the bases of its acrylic salt and pepper mills, Cole and Mason has increased productivity and managed to cut costs

Originally using nylon plastic guards, Cole and Mason now make the guard out of ABS in order to use the ultrasonic welding machines, as ABS has the same melting point as the acrylic mill casings. There is a varied range of acrylic mill sizes and shapes; however, the fittings onto which the casings are loaded can be changed easily to accommodate the differences.

The two machines are incorporated into different production lines to cope with different workloads. The rotary plastic welder has six fittings to handle the large volume orders for the acrylic 505 mill family. To allow continual loading on and off, without stopping the machine, the mills are rotated under the welding horn one by one. Safety flaps prevent anyone reaching for the mill while welding is in progress. For acrylic mills made in smaller volumes, a "shuttle" plastic welder was bought which has two fittings and is activated by the closing of a drawer.

"We chose ultrasonic welding because it offered us the opportunity to speed up and streamline production without having to redesign our mills", explained Brian. Equally important was the cleanliness of the ultrasonic process as the cleanliness of the assembly lines has to reach the highest standards to avoid any contamination.

For further information contact: Kerry Ultrasonics Ltd, Hunting Gate, Wilbury Way, Hitchin, Herts SG4 0TQ. Tel: + 44 (0) 1462 450761; Fax: +44 (0) 1462 420712.