OEE: Overall Equipment Effectiveness and Its Unintended Side Effects

Have you heard of overall equipment effectiveness, or OEE? If not, it’s time to learn; OEE is a standard practice in many top tier production conglomerates and helps to measure certain impacts on your business that might, without a proper system, seem abstract or intangible. Basically, overall equipment effectiveness operates on the premise than any part of your production process that occurs can be quantified and used to determine the most efficient operating procedures for your business. As the name implies, OEE is mostly concerned with machinery and equipment, especially when machine maintenance, breakage, and productivity metrics are key to the livelihood of your business. While this article gives a brief overview of what OEE is, we’re also going to be looking at some of the unintended (positive) side effects to making use of such a system. As with any proposition to implement a new number crunching regimen, taking on OEE can seem like a hassle that won’t pay off on the time you put in. Hopefully, after having a read through, you might just think otherwise.

OEE Basics

OEE comes down to taking the types of time-loss factors workplaces commonly experience and putting them into measurable means. To accomplish this, all machine-related production delays are divided into three primary categories.

Availability: Availability losses have to do with machine downtime that renders stations inoperable to workers, and thus “unavailable” to produce goods. This downtime is further categorized into either planned downtime or unplanned downtime. Planned downtime basically just involves scheduled maintenance, upgrades, and machine replacements. Unplanned downtime involve errors in machine behavior that necessitate maintenance and special attention. It is important to know that all time losses associated with any unplanned repairs or machine downtime should be included as well. Think about things like the time it takes to wait for support, supervisors, paperwork or maintenance crews, etc. Breaks in which all available workers for a machine are on lunch or otherwise unavailable also count towards this tally.

Performance: Performance losses have to do with times when, despite a machine being up and running, certain settings or employee practices are causing it to produce at a less than optimal rate: Workers who can’t keep up with loading or unloading a machine, materials not feeding into a process properly, or equipment failures that require restarts (though not complete shutouts) will fall under this category. It is also important to make note that when machines are down it is highly recommended that specific safety signage (which can be found here) be utilized to ensure the safety of employees. Certain settings, especially imprecision, on machinery might also qualify as performance-based losses of time. Here’s an example of just that,

…operators may be reluctant to let the control system set a control valve at its design position. Instead, they will leave the valve at a very conservative position. This conservatism can reduce attainable throughput by as much as 5%.
-Futuristix – Overall Equipment Effectiveness

Cases in which new machinery is being optimized or in which employees are not yet completely comfortable with a new machine or system can often cause these types of time losses.

Quality: The third and final consideration is product quality. Losing production time due to quality issues usually means that products are coming out either completely defective or in such a state that they require additional work to be shipped, even thought they should be finished at the given stage. Repeated quality issues can indicate worker shortcomings, machine malfunctions, or both.

Once you’ve gathered your various time loss factors in one place, you will calculate how much time is lost in each instance. This is usually done by associating an event (a machine breaking down), with a loss of productivity (X amount of work minutes/hours/days lost). Ultimately, this allows managers to avoid guessing at where their biggest areas in need of attention lie; you can address your replacement, maintenance, and training efforts at the areas you calculate to be most in need.

Why Utilize OEE

Business of varying sizes that have implemented OEE programs only to find that they’ve enjoyed some unforeseen benefits, not the least of which being safety.

When machines are corrected to run without breaking, jamming, or otherwise stalling production, safety statistics tend to rise given a large enough sample time. Why is this? The less machines are down, the less guards are removed, the less hands are stuck in and around moving parts, and the less employees have to climb on top of machinery in places they shouldn’t be.

Well-oiled machines, both figuratively and literally, also mean that workers don’t have to fidget with getting materials to fit right. When a machine has a problem, a worker might have to choose between completely stalling production to shut the station down, or engaging in unsafe manual tampering to get things running smoothly again. Not wanting to be seen as unproductive or slowing things down themselves, many workers might opt for the more risky route.

You’ll also likely realize a long term decrease in operating costs, as emergency repairs often cost more and indicate a more serious problem than regular upkeep. Additionally, producing fewer defective items means that you won’t have to waste more materials making the same thing. Your biggest, most obvious source of improvement will come from the increase in efficiency production. This can be used to reduce your current costs by scaling back the number of employee hours needed to maintain production levels, or it can be used to grow your business by producing more goods for more clients with the same initial capital and time inputs.

In any event, OEE has proven itself time and time again to be an effective management tool for ironing out efficiency issues. With revelations that the technique can improve safety metrics and other measures as well, there’s no better time than the present to start using it for yourself.