Mold Maintenance & Repair

OCT 2013

Mold Maintenance & Repair

Issue link:

Contents of this Issue


Page 12 of 27

The PM toolmaker may decide to use a portable dry-ice blasting method during an inpress PM. The use of dry-ice blasting does not require the mold to be cooled down—in fact, the heat of the mold actually enhances the efectiveness of the dry-ice blast method. This technology uses compressed air and shaved dry ice to clean mold surfaces and remove residue without introducing any contaminants. The efect of small particles of ice hitting the mold surface at high speeds with the extreme temperature diference between the hot mold surface and the dry ice (-109 F/-78 c) makes for an efective scrub without leaving any residue behind. This cleaning method process is approved by the ePA, usdA, and FdA. While the setup of the dry-ice system initially adds a small amount of time to the event, it signifcantly reduces overall PM time (which is downtime) by keeping the mold in the press and out of the shop. dry-ice cleaning is used for both in-press and on-the-bench PM. it is an efective and safe cleaning method for all steels, including polished surfaces. says Mgs germantown's tooling engineering manager, Mike Welnak, "We have documented a signifcant reduction in mold downtime since we deployed the dry-ice system. We run a wide range of engineered resins in both conventional and highly engineered tooling systems and this technique has proven to be efective on many in-press applications." When the PM schedule calls for a full preventive maintenance event, the mold will be taken out of the press and into our PM shop. Here it is treated like the celebrity it is and is greeted How Other Molders Approach Mold Cleaning "Rogan's policy specific to mold cleaning and inspection applies to all molds, after the mold is removed from the molding press and before it is put back in its storage location. Mold faces are cleaned with mold cleaner and a clean rag, and/or compressed air. All water lines are cleared with compressed air, and all plastic and molding residues are removed. For diamond-polished surfaces, Rogan uses mold cleaner and compressed air only. We also make a point to check for scratches, chips, cracked cavities, broken cores, core pins, ejector pins, missing components, broken leader pins and bushings, and warped or burred plates." Jim Ritzema, Direction of Operations, Rogan Corporation, Northbrook, Ill. 3. The third is a PMXXXX (mold #). This PM has a specific instruction; a predetermined frequency based on run-hours, and it comes to the toolroom on a unique work order, which must be completed before the system will allow the job to be scheduled into the press." Shawn Dusing, Manufacturing Engineering Manager, Donnelly Custom Manufacturing, Alexandria, Minn. "At Donnelly, we have three categories of preventative maintenance, depending on the need of the individual mold: 1. We have a standard PM initially set up on a 250 run-hour frequency, this is adjusted up or down as necessary and includes a generic instruction for cleaning the mold components. 2. We also have what is called a CCPM where the mold is scheduled for cleaning as soon as an order is entered into the ERP system. This PM contains specific instructions on what issue needs attention prior to the mold going into the press, regardless of run hours logged on the mold. An example may be "vent pins" in specific areas. "One of the things we do for injection mold Preventative Maintenance is use environmentally friendly mold solvents in cleaning all the sub-components of a mold. The type of solvent used does not require additional wipe-down after cleaning. This is a dramatic improvement in the method we used prior to this, which required a secondary wipe-down on all the components just to get rid of leftover residue. We also have eliminated shop rags from our tool room and strictly just use White Wipe All's. We eliminated shop rags for tooling because they could be used with other types of chemicals that could have a negative impact on surface steel, and the rags tend to collect chips or debris that could damage polished surfaces." Steve Feaster, Injection Molding Plant Manager, Currier Plastics, Inc., Auburn, N.Y. "We still do it the old way, tearing the mold apart, and either using a plastic bead air blast or polishing compound." Per Flem, Owner & CEO, Recto Molded Products, Cincinnati, Ohio October 2013 11

Articles in this issue

Archives of this issue

view archives of Mold Maintenance & Repair - OCT 2013