Downtime planning

by Kendall McFall
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Former United States (U.S.) president Dwight Eisenhower, the commanding general for the allied invasion of Normandy, expressed clearly that he believed in planning. He was also well aware of the harsh realities of battle, meaning that when the battle begins, new information, real-time trials and unforeseen events are going to come rapidly. As a leader, his ability to react to the changes would only be as good as the focused attention given to creating the battle plan.

Repair days in a flour mill are not epic battles, but planning that is focused toward an expected outcome does lead to measurable improvement to a mill’s bottom line. A plant’s expected outcome from a well-executed repair day should be that the mill will operate without unscheduled shutdowns or systems running at reduced capacity. Focused repair day planning can help with both.

Repair day planning should involve all mill employees, not just the maintenance crew. My time in a commercial mill was spent before there were computer-based preventive or predictive maintenance programs spitting out lists of work on command. I was trained in the now-ancient art of pencil and paper maintenance planning, and as a result I relied heavily on those people with the most experience.

My regret is not developing a way to involve more of the crew in the planning process. Certain work done according to a schedule, like roll changes and sifter sections, dominated the repair day, and rightly so. However, often some piece  of equipment needing a new belt or sprocket was left off the list because the person with the information wasn’t involved in the planning process. Occasionally, this lapse would cost the company production due to a breakdown at startup. Regardless of the reason it occurred, it always frustrated the shift miller who had to deal with a second startup and extending the work day of the maintenance crew when they were ready to go home.

PREPARING A REPAIR LIST

Planning for a repair day starts before the shutdown. If we prepare our repair list an hour before the wheat is off the mill, there is a good chance that something in need of repair will be either left undone or fixed temporarily because the right materials were unavailable.

A miller whose facility is located in a remote area may need to plan shutdowns five to 10 days in advance, whereas a miller whose mill is in or near an urban area may only need two days due to the accessibility of bearing and belting suppliers. Unforeseen problems aside, too

much repair time in mills can be spent by the technical people “tooling up” for the job. Preplanning the jobs with respect to tools and parts needed and having them delivered to the job site prior to the wheat coming off the mill certainly helps to improve the efficiency of the maintenance people.

Planning helps to balance repair demands with available resources. Every repair day carries with it a certain number of compromises. Seldom do mills have the human resources available to accomplish every item on the maintenance list. However, in many cases repair days carry added significance in that they also provide the time for internal system cleaning and sanitizing.

A 24-hour-a-day, seven-day-a-week operating schedule makes it nearly impossible to balance the available crew between repair work and sanitation work. Given this challenge, it can be beneficial in many instances to outsource certain portions of the downtime work to third-party vendors. Jobs such as filter sock exchange, bin cleaning and, in some cases, sieve repair might actually be less expensive if carried out by a vendor with individuals specifically trained for the job.

While certainly not the right solution for all plants, the realities of rising food  safety standards and minimal operating crews require managers to take a more creative approach to accomplishing these repair and sanitation tasks. The planning process can be used to provide the mill manager with the documentation and the cost-versus-benefit analysis to make the right decision for the plant.

Finally, included in the plan for the repair crew should be a “to do list” for the mill manager during repair day. Allowing for a moment to relax on a repair day may be warranted, but using this time to survey the mill with a critical eye may be just the thing that moves us beyond where we’ve been in running efficiencies. A visual inspection of belts and chains that are not on the list for repair and listening for compressed air leaks are easy ways a manager can contribute to a successful repair day.

Beyond the obvious, though, a mill manager can learn a lot about the mill by closely examining the rolls. Questions the mill manager should consider include: Where is the roll wear occurring? How fast is it happening? Is the wear consistent across the entire roll surface or are there abnormal wear points? For example, a small band of wear circling the roll may indicate improper tramming, while lines of wear down the length of the roll (thin lines that appear to shine in comparison to the matted surface) may indicate overloading at that passage. Nicks or gouges on fluted rolls, or a shortened life, are often indicative of problems in the cleaning house stone removal equipment. Planning your own time with a purpose in mind can do as much to improve the mill operation as a well-focused repair crew.

Downtime planning can be used to move from the present situation toward the achievement of one or more objectives or goals. By involving a broader group of employees at the plant, planning as far in advance as possible and getting creative with respect to human resources, the plant’s downtime effectiveness and, ultimately, the efficiencies of the entire operation will improve.

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