Part Two of a Two-Part Series Optimizing Mold Performance And Maintenance Efficiency
The last three steps of a six-step process for strategizing for improvement in shop operations when it comes to how we maintain molds.
Last month (December 2006) we discussed how optimizing mold performance and maintenance efficiency are different, yet work hand in hand to impact the overall profitability of a molding company. We discussed the first three steps (Clean-up and Organize, Stop the Bleeding and Assess the Damage) of a six-step process and typical objectives to overcome.
In the article a chart was shown that demonstrates how to assess the damage by tracking all unscheduled stop reasons to determine the most serious or #1 issue (based on tooling and labor or corrective action costs) that shut down production and the total number of these occurrences. It also is important to remember that the corrective action costs do not reflect press downtime and lost production, which could add greatly to the overall cost of the unscheduled mold stop event.
Having access to the frequency, conditions and contributing issues surrounding these stops represents the most rudimentary of initial steps to begin improving mold performance. When you acquire the ability to track and target unscheduled downtime events, you then begin the process of moving from a completely reactive culture into a more profitable, proactive one.
Data as a Resource
Data is necessary to accurately determine exactly where and how repair hours are being used. The typical reaction to unscheduled breakdowns is panic, frustration and immediately assessing blame. The reaction should be to use available data to “work the problem” to achieve root cause identification, if possible, or at minimum, better understand the variables involved.
Efficient and accurate troubleshooting is dependent upon our understanding of how the many molding variables in conjunction with maintenance practices, impact the mold design features which prevent us from: (a) molding our part to a spec or (b) running the mold efficiently. If there is no clear-cut resolution to eliminate the defect, then the next step is to better control the inconsistencies that exacerbate the design weakness. This is where categorized data earns its money. You simply cannot rely on memory or random journal entries made manually or electronically in which to base decisions.
Step 4: Count the Issues
Once unscheduled mold stops are categorized, the next step is to count all occurrences to see where your problems really lie. Unscheduled mold stops should be documented at the press by process personnel into a system that organizes and tallies the frequencies.
It is here where most shops in the early stages of data assessments are truly shocked at the results. Things are never what they seem. Why? It is human nature for people to remember particular maintenance events more vividly and many times, differently than others based on their own interaction with the event. For instance, repair techs easily recall procedures or events that cause physical pain such as skinned knuckles, pinched or cut fingers. Molds or components that are unwieldy or tedious to work on create anxiety that can bias opinions concerning labor hours required to perform simple tasks. Conversely, issues that are readily corrected through a simple procedure or by installing new tooling are easily forgotten, even though the collective dollars put it at the top of the “things to be concerned with” list. After you have accumulated enough mold stop data to create a list of targets, the next step is to figure out what you want to go after.
Step 5: Prioritize
Prioritizing or setting a maintenance schedule for your shop will be dependent first upon production requirements. Determining this is not something a toolroom supervisor will readily know (unless he molds mostly long-running jobs) without first meeting with production and process personnel.
One thing I find amazing is the number of shops that do not even attempt to develop a production schedule, instead relying on a “shoot from the hip” mentality in terms of projecting sales (i.e., workload). Even a couple of days notice of a potential mold run would give many repair shop managers the ability to more wisely utilize the time they have a mold on a bench, through job scheduling.
In last month’s chart example, Mold Damage was at the top of the list in both frequency (17) and corrective action dollars ($41,555.76). This would make it the likely #1 target for our shop. At this point the Mold Damage occurrences would be sorted by distribution to see exactly what molds were stopped for damage, when, what tooling was involved, etc. to narrow the field down to a manageable goal, which according to our chart, would be the 51895-CN mold. See Chart 1 (sorted by repair costs). This type of report also makes it easy to sort and filter on different column headings looking for information that might be related to several of the mold stops regardless of mold type.
Optimizing mold performance and maintenance efficiency should be taken one step at a time in order not to be overwhelmed and to maintain focus. If necessary, all documentation referring to the production run and relevant shop records should be collected and reviewed further for other linking information.
In prioritizing secondary targets, I always look for maintenance items that could be eliminated or significantly reduced by simply making repair techs aware that an issue exists, such as the following maintenance issues.
These type of issues that involve incorrect installation techniques or oversights cause much heartburn with process. Though maybe not in the top five of occurrences, these issues always get a lot of publicity in the corner office, so that makes them viable targets in my book.
Target Maintenance Issues Second
Establish shop targets/goals based on frequency and simplicity of the corrective action first.
1. Maintenance Mistakes
a. Internal water or oil leaks due to missing, cut, twisted or wrong size o-rings and seals
b. Missing, loose or stripped SHCSs
c. Repetitive electrical issues such as bad heaters, probes, thermocouples and loose or shorted connections. (lack of Final Check procedures)
d. Missing tooling or incorrect tooling/mold assembly
e. Incorrect cleaning techniques (leaching solvent or uncleaned vent residue)
f. Incorrect greasing (too much or too little)
g. Repetitive parts or runners sticking (no corrective action applied)
h. Mold damage by improper handling (nicks, dings or burrs in tooling)
Step 6: Act
Now that you have targeted issues for your shop to investigate, follow through with mold maintenance plans that directly address these issues. Publicize frequencies, defect corrective action costs and lost production calculations to give repair techs a sense of value to their actions versus just printing out a work order that states “Clean and Rack” or “PM Mold.”
Changing a maintenance culture to think proactively is dependent upon systematically choosing targets based upon accurate data, diligently going after them and then continuing to monitor these defects for improvement or change.
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