Mastering your work - a Japanese Chef

I was recently on vacation in the beautiful foodie heaven of Vancouver, BC. After a long day of sight seeing on Victoria Island, my girlfriend and I decided to have some Japanese food in the downtown area at a restaurant named Guu. I was definitely not prepared for the epic cooking mastery that I was about to witness. We got a perfect seat at the bar area facing the chefs. After watching in awe for about an hour and dining on some scrumptious food, I decided to film what looked appeared to be their head chef. Have you ever been to a factory and watched an operator just absolutely master an operation? It was like that but considering the mixed model and variable demand that a chef has to deal with, it was extra special. Enjoy the show.

The Missing Pareto line - Who cares?

Pareto Analysis is a critical part of the practical problem solving process. Paretos help you prioritize your problems so you can systematically address them. Paretos have two components:
  • Bars sorted in descending order by whatever categories you're measuring
  • Cumulative percent contribution line
A proper pareto
I made up a pareto of defects above. This graph counts defects for Acme company sorted by defect type. Most people easily grasp the whole sorted bar concept, but don't quite understand the cumulative line. I've seen many paretos where people just leave it off. They're probably thinking - "well, I know what my top bar is - I'll go work on that." Yeah, that's true - they know what their top bar is - but do they understand the affect improvements are going to have on their project? That's really what the percent contribution line does for you - it helps you estimate how much of that gap you are really going to close by improving the selected bar(s).

For example, lets say my boss at Acme Company says "You better reduce those defects by at least 75%". I look at my defect pareto and it clearly shows me that if I just address the top bar (scratches), I'm only addressing 43% of my problem. The percent contribution line immediately shows me that in order to close the entire 75% gap I have to address the top four pareto bars (this assumes I completely get rid of that defect type). Without the percent contribution line, I might have just gone off and fixed scratches then been left scratching my head trying to figure out why my boss was yelling at me!

My point here is don't forget that extra line on the pareto and don't let people tell you its not important.

SpikeTV's "Coal" and Lost Time Analysis

I've been watching this great new show on Spike called "Coal". It documents the trials and tribulations of a group of miners and supervisors at a coal mine in West Virginia. It's exciting TV because you realize just what these men are risking to support their families. It seems to be an incredibly dangerous profession, but I definitely understand why they're willing to sign up. In a state where the median household income is about $36,600 (2009), a coal miner starting salary is on average $60,000.

A recent episode really stood out in mind. The team was having average production on dayshift but was failing to meet their targets on the night shift. The mine operators were scratching their heads and wondering why they weren't hitting their targets on the off-shift. Whenever the drilling machine (continuous miner I think is what they called it), wasn't running, they weren't adding any value. A variety of things were causing the drill not to run - e.g generator failure, pump failure, conveyor belts jamming, ventilation fans shutting off, etc.

The mine's solution to their problem was to bring in a "hired gun" - a contractor to take over as the shift supervisor and solve the problems. After a couple of shifts, he quickly identified the generator failure as their biggest source of downtime. When the drill was run too fast, it would bind up and kick the generator, effectively shutting down the mine for 15 minutes. This would happen several times during the night shift due to an inexperienced drill operator, costing the mine thousands. This very observant "hired gun" was able to identify this fairly obvious root cause but it seems the mine would have benefited from a lean tool called Lost Time Analysis.

In Lost Time Analysis (LTA), you track production time (planned and unplanned) you lose to a bunch of different causes. Typical causes are like "machine down", "tooling change", "absenteeism", or "preventative maintenance". You can assign codes for each cause like 01 is machine down, 02 is tooling change, etc. Whenever the machine - whatever machine you are tracking - isn't adding value, you log the time you lost and assign it to the appropriate cause code. After a set period of time, management or engineering paretos and reviews the data with the team. The team might see that they are spending an excessive amount of time on tooling changes so maybe its time for a changeover reduction event.

Lost Time Analysis might have looked like this for the mine (simplified obviously)
For the "Coal" mine, they could have used the aforementioned causes like generator failure and conveyor belts. Whenever the drill wasn't running, they could log the cause and note the minutes they lost. Their pareto should have showed them what that "hired gun" figured out - that their generator was too small. In an industry where minutes cost you thousands of dollars in lost production, measuring and understanding your downtime seems critical.

Have any insight on what kind of systems they use in the mining industry or have any past experiences in your industry with lost time analysis? Please share.