PHASA assembly is key to productivity

Citation

(2002), "PHASA assembly is key to productivity", Assembly Automation, Vol. 22 No. 3. https://doi.org/10.1108/aa.2002.03322caf.002

PHASA assembly is key to productivity

Keywords: Plastics, Rivets

A PHASA 20/40 series machine producing 90 off riveted fixings every cycle is the key to high productivity on critical assemblies at the heart of central locking control units for Scandinavian vehicle manufacturer Saab (see Plate 2).

Plate 2 Plastic hot air staking technology from PHASA Developments has been selected for the production of critical PCB assemblies at the heart of central locking control units for Scandinavian vehicle manufacturer Saab#

The equipment, from Harlow-based PHASA Developments, is used to secure moulded key fob housings to PCB motherboards, which are nested together to allow 30 individual units to be processed in a single cycle. In operation, the motherboards are first mounted in a special-purpose turnover fixture. Individual key fob housings are then positioned onto the PCB from above, using three moulded pegs for location. The fixture subsequently clamps the components in position, before inverting them ready for the hot air staking process.

During the PHASA machine's automatic cycle, a custom-designed manifold arrangement directs air at 300°C precisely over the 1.5mm diameter pegs to bring them to their plastic state. Cold forming tools then reshape them into riveted heads, which cool and solidify to produce a permanent, vibration proof fastening.

According to PHASA's John Neugebauer, the development of the latest equipment for Saab follows the success of a similar contract for Rover. "We have proven the suitability of plastic hot air staking for this type of work over a number of years. Our track record includes refining the process to produce more than 200 fixings in a single operation. As a result, customers throughout the telecommunications, IT and domestic appliance sectors can undertake PCB assembly applications extremely cost-effectively.

"The system's ability to assemble 30 off units within a single 16 second cycle is a key factor in achieving our customer's required production rates. What is more, this capability is backed by inherent repeatability and consistency, which enables C_pk figures in excess of 2.0 to be achieved by most users – the equivalent of less than one reject per million operations."

"Hot air staking not only offers a simple and effective method of producing permanent, low-cost fastenings, but is also suitable for the pre-loading of seals, or the retention of bearings and threaded inserts", he continues: "It has therefore become a first choice assembly method for thermoplastic materials across a wide range of automotive industry applications – from lamp assemblies to interior trim retention."

For more information contact: International House, Horsecroft Road, Harlow, Essex CM19 55U, UK. Tel: +44 (0) 1279 630200; Fax: +44 (0) 1279 630222. E-mail: sales@phasa.co.uk; www: phasa.co.uk