Hood Flexible Packaging Saves $50,000 by Reducing Film Scrap
Changes in setup and extrusion reduce plastic film scrap in the printing industry.
Hood Flexible Packaging manufactures bags and plastic film used to package food and other items. Hood employs approximately 130 people and operates 24 hours a day, seven days a week. The company has three main departments: extrusion, press and converting. The extrusion department manufactures rolls of plastic film using a blown-film process, then treats the film to accept ink. The press department prints on the film which is then sent to the converting department to be made into bags.
Incentives for Change
Hood produced 900,000 pounds of plastic film scrap in 1996, giving them a scrap rate of 6.5%. Knowing that the average film scrap rate for the flexographic printing industry is 4%, the company set a goal to reduce the overall weight of their film scrap by 20%.
Identifying the Main Source of Scrap
Because Hood knew that close to 50% of their film scrap was coming from the press department, the MnTAP intern evaluated each of its scrap-producing activities. A form was developed to help press operators document when and how much scrap was generated. Information was also gathered by weighing scrap and using footage counters that measure the length of film used.
The intern found that between 70% and 75% of the film scrap from the printing operation was produced during setup. Setup is the process in which a print job is prepared to run on the press. Equipment is readied, and print quality is tested and adjusted at this time.
The project resulted in savings of $50,000 a year and the facility reduced scrap film by a projected 104,000 pounds for 1998.
Train Press Operators
How press operators do their job has a big impact on the volume of scrap produced. By documenting how the more experienced operators prepared for print jobs, Hood was able to develop training to ensure that employees across all shifts are following the same best setup procedures.
Press operators were trained to stop the presses, whenever possible, while adjustments are being made. An estimated 15 percent of the film scrap was produced while the presses were running during adjustments. Hood will also make certain that equipment needed during setup is in place before the press is started.
As Hood formalizes its quality procedures, they are stressing the importance of ongoing training and the use of job standards.
Order Setup Film
Hood was using off-specification film from their extrusion department as setup film. While this in-house reuse system reduced scrap in the extrusion department, it increased the volume of scrap in the press department because the film was wider and thicker than necessary for setup.
Two steps were needed to reduce this film scrap. First, the extrusion department needed to produce a lighter weight film just for setup. Second, a regrind unit was needed to minimize the waste from extrusion.
Step 1: Film Specifications
Printers can use setup film that is thinner and not as wide as the film specified for the actual print job. Although the same linear feet of film is required to prepare for printing, the actual weight of the scrap is reduced.
Operators need to know the standard length of setup film required for preparing jobs for each press. It is also helpful for them to know if a job has a history of difficulty and to order more film to accommodate the additional adjustments.
Hood’s press department now orders setup film from extrusion, specifying the desired length and width, and 1.25 mil thick—the thinnest film that will provide proper results.
Step 2: Regrind Equipment
To manage the film scrap that is no longer being sent to the press department for setup, the extrusion department installed a second regrind unit and upgraded equipment. These improved quality and reduced scrap at the extrusion process. The scrap that is generated can now be reground into new feedstock. When all of the scrap cannot be mixed with virgin resin to make new film, the clear scrap film has a better sale price for recycling than printed scrap.
An implementation team was designated to carry out the recommendations. The team consisted of the Printing Department supervisor, the Extrusion Department supervisor and the purchasing agent. Previously, the three departments had not worked directly together. Successful implementation required all three to be involved.
Including the purchasing agent in implementation planning helped expedite the purchasing of the grinder and improved the timing of the project.
Additional Recycling Option
Segregating film scrap at the printing presses would allow for unprinted scrap film to be sold for a higher price than the printed scrap. This option was not implemented due to space constraints near the presses.
The scrap rate from the press area has been reduced to 4.5%, exceeding Hood’s reduction goal. Because the extrusion department was involved in the project, the waste was not merely shifted between departments. To help maintain the lower scrap rate, press operator training will be ongoing at Hood. The facility saved $50,000 a year and reduced scrap film by 104,000 pounds in 1998.