How VMAC Reduced Its Rotor Production Time with Kata Experiments

VMAC is committed to lean manufacturing, a style of manufacturing that aims to reduce waste through continuous improvement. In celebration of Manufacturing Month, we wanted to share how we applied one lean tool—the Kata Improvement Method—to improve rotor production here at VMAC.

kata-experiment

Kata Improvement Method

Many tools can be used to reduce waste in lean manufacturing, including the kata improvement method. Kata involves four steps:

  1. Identify The Challenge
  2. Understand The Current Condition
  3. Determine A Target Condition
  4. Conduct Experiments

Kata uses quick, rapid experiments to determine whether a change will help the team reach their target condition. In many cases, several experiments are required before the kata team can successfully reach their target condition. That’s expected! By making one change at a time, we can determine whether any given change is an improvement.

VMAC Rotor Improvement Kata Experiment

VMAC used the Kata Improvement Method to try to reduce the time it takes to make rotors. Our rotors are a core component of every air compressor we manufacture and a cornerstone to VMAC’s success. The faster we can make rotors, the more air compressors we can produce within any given timeframe.

1. Identify The Challenge

To begin, the kata team identified their challenge and created a clear goal for their kata experiment: “Increase rotor capacity without increasing staff or shifts.” The challenge statement also had a specific numerical target that is publicly redacted.

2. Understand The Current Condition

On the surface, the current condition may seem straightforward, but understanding the condition of a process requires in-depth analysis.

First, our team made a block diagram of the entire process, identifying each step of the rotor production process. Then, each step was timed through numerous cycles, identifying the number of seconds required to complete the individual steps.

By mapping out the current condition of VMAC’s rotors, our team identified something peculiar: some aspects of the machine process were taking three times as long to produce within the female rotors when compared to their male counterparts. Male and female rotors are of different shapes, but this much discrepancy in time did not make sense. This discovery was something to come back to…

3. Determine A Target Condition

At this point, the kata team was ready to set their target condition. The team identified the following target: decrease the rotor cycle time by 10%, by a set date.

4. Conduct Experiments

Now that the kata team had identified their challenge, understood the current condition, and determined a target condition, they were ready to experiment!

Experiment 1

The first experiment tackled the anomaly in which the female rotor was taking more time to produce than the male rotor. The team decided to try to reduce the time so that the female rotor feed rate would match the male rotor feed rate.

One of our machinists carefully analyzed the code and was able to identify the issue. While the male rotor code focused on the task at hand, the female rotor code had “look ahead routing” pre-programmed. Look ahead routing allows the machine to plan for the next steps, but it was causing unnecessary pauses within the production process.

By removing the extra code from the process, the kata team was able to cut the female rotor production time in half. This improvement was a significant accomplishment, and the experiment was a success.

However, the female rotor production was still slower than the male rotor, which meant there was more experimentation to do.

Experiment 2

The second experiment focused on further improving the movement and feed speed. The team continued to analyze the code for improvements that could speed up the male and female rotor creation process.

During this experiment, the kata team discovered the code was intentionally controlling the speed that the machines moved while creating the rotors and had some other inefficiencies. In other words, the pre-programmed code was causing unnecessary delays.

By further refining the code, our kata team was able to decrease the finish time by increasing speeds and feed times, and changing 2D movements to 3D movements.

The total rotor cycle time was improved by 13%, exceeding the target condition. The challenge to “increase rotor capacity without increasing staff or shifts” was met, making the kata Improvement project a success.

Why Kata Experimentation & Lean Manufacturing Is Important

VMAC's first rotors

Lean manufacturing is a mentality of continuous improvement, and the kata improvement method is one tool we can use to improve. When we challenge the status quo, we find ways to manufacture our products faster and more profitably than before. Rather than accepting that something should be done the way it’s always been done, we find ways to improve upon our past.

In the case of the rotors, we identified code discrepancies that were creating time waste and slowing down the process. By removing this waste from the process, our team was able to significantly increase rotor production, without adding any staff or shifts. A 13% improvement in the rotor cycle time allowed VMAC to create 21% more rotors.

Thanks to a lean manufacturing mentality and the use of kata experimentation, VMAC now makes more rotors in a shorter period. But this is just one example of how lean manufacturing leads to clear, tangible improvements. VMAC participates in hundreds of continuous improvement initiatives every year, as we encourage our teams to explore new ways to work smarter, better, and leaner.