Injection moulding process monitoring system reduces rejects to less than three percent

Investment in a new process monitoring system has resulted in the reduction of rejects from 20 percent to less than three percent at a South-Wales based injection moulding manufacturer.

Waldon Ltd installed the new ‘CoMoNeo’ process monitoring system from Kistler Instruments to enable cavity pressure-based analysis, optimisation, monitoring and documentation of the injection moulding process following on from the success of an earlier version of the technology in 2009.

The new system builds on Kistler’s original cavity pressure monitoring system through increased ease of operation and user friendliness, as well as providing more detailed information on the production process. In particular, CoMoNeo identifies rejects more precisely, including notification of which cavity produced the reject, and delivers them automatically to a robotic handling system for recycling.

At Waldon’s manufacturing site, the high level of process control and monitoring provided by the new system allows it to run its injection moulding machines ‘lights out’ for 24-hours a day, six days a week with any problems being advised to the duty maintenance engineer by mobile phone.

The precise control over the entire injection phase delivers a CPK, the measure of process capability, of better than 1.33 to be achieved consistently. In addition, reject parts have reduced from 20 percent to less than three percent, with a zero ppm forecast.

The design of the software is predicated on operational simplicity by using advanced technology to minimising the need for manual input. “The user-friendliness of CoMoNeo means that the systems benefits are achievable without heavy dependence on a senior, experienced engineer. In fact, they are now accessible to good semi-skilled technicians,” said Richard Kempa, Waldon’s Commercial Manager

In addition to making the initial setup faster and more accurate, this approach ensures that the production process is continually monitored with high precision, false rejects reduced and faulty components eliminated from the production line.

This improvement in reject detection is allowing Waldon to expand its marketing to high precision sectors such as medical products, where customers demand a guarantee that every moulding delivered is within specification.

The use of the system has also led an existing customer to place orders for three new mission critical components of automobile sensing systems.