Improving Productivity of Molding Machines for a Plastics Manufacturer

Reducing Changeover Time: Improving Productivity of Molding Machines for a Plastics Manufacturer

Client:  A designer and manufacturer of consumer packaging.

Goal:  Reduce the changeover time of molding machines to increase capacity and reduce lead time from order placement to order fulfillment.

Requirements: The company is consolidating product lines into product-center oriented facilities. This will require the machines in all facilities to changeover molds more often. A 50% reduction in changeover time is required.

Initial Tasks: To frame the improvement event, a Daniel Penn consultant conducted a lean and kaizen principles training session. The team went to work by reviewing data obtained from a changeover of a similar machine and mold that was performed to prepare for the workshop.

Findings: The time observations gave the team baseline numbers from which they established the 50% time reduction goal. During the pre-event trial, they witnessed several interruptions of the process, missing equipment, a mold that hadn’t been engineered for the machine and other issues that came up during the changeover.

Reducing Changeover Time

Actions: The first trial of the event was conducted with the troubleshooter/mechanic changing out the mold, but with interruptions from other production issues. Several improvements were identified from review of video that capture the mechanic’s activities. Even with little preparation, significant reduction in time was realized. The key point the team took from the first trial was the mechanic works best with support from another mechanic.

For the second trial, advanced preparations were made. Tooling was identified and arranged for ease of access and sequence of use. Support equipment (ladder, crane) was staged for ready access. The mechanic worked in an uninterrupted manner, and along with ease of access to tooling and support equipment, performed the changeover in about a quarter of the time from the pre-kaizen observations.

During its presentation to senior management, the team recommended that the mechanic be dedicated to the changeover task. Another significant recommendation was the installation of a valve assembly to reduce the time for bleeding and re-filling the water system for the mold. With the addition of key visuals, the mechanic won’t have to think twice about the sequence in which to operate the valves.

Project Baseline to Benefits Comparison

The initial changeover trial of the workshop realized an improvement of 65%. The second trial realized an improvement of 73%. With this level of performance and improvement across the 14 machines in the facility, the company will now realize a 23% increase in capacity on an annual basis, essential to meeting revised productivity goals and their plant-based product and design plan.