Learn how to calculate RTY and use it to identify and eliminate waste in your processes.

Key Takeaways:

  • RTY calculation is a formula that multiplies the first pass yield of each process step to show you the probability of producing defect-free outputs.
  • RTY calculation helps you find and fix the root causes of defects and rework in your processes and improve your process performance.

If you’re looking for a simple and effective way to measure and improve your process efficiency, you need to know about RTY calculation. RTY stands for Rolled Throughput Yield, and it’s a metric that shows you how likely your process is to produce defect-free outputs.

RTY calculation is based on the concept of Six Sigma, which is a methodology for achieving excellence in quality and performance. Six Sigma aims to reduce variation and defects in processes by following a structured approach of Define, Measure, Analyze, Improve, and Control (DMAIC).

One of the key steps in Six Sigma is to measure the current state of your process and identify the sources of waste and inefficiency. This is where RTY calculation comes in handy. RTY calculation helps you quantify the cumulative effect of defects and rework on your process output and throughput.

What is RTY Calculation and How to Do It

RTY calculation is a simple formula that multiplies the first pass yield (FPY) of each step in your process. FPY is the percentage of units that pass a process step without any defects or rework. For example, if you have 100 units entering a process step and 90 of them pass without any issues, your FPY is 90%.

To calculate RTY, you just need to multiply the FPY of each process step. For example, if you have a four-step process with FPYs of 90%, 80%, 95%, and 85%, your RTY is:

  • RTY = 0.9 x 0.8 x 0.95 x 0.85 == 0.58

This means that only 58% of the units that enter your process will come out defect-free, and the rest will either be scrapped or require rework, which adds to your cost and time.

RTY calculation gives you a realistic picture of your process performance and reveals the hidden factory of rework and waste. It also helps you compare different processes and identify the ones that need improvement.

How to Use RTY Calculation to Improve Your Processes

Once you have calculated the RTY of your process, you can use it to find and eliminate the root causes of defects and inefficiency. Here are some steps you can follow to use RTY calculation for process improvement:

  • Identify the process steps with the lowest FPY and focus on them first. These are the steps that have the most impact on your RTY and your process output.
  • Analyze the data and information related to the low-FPY steps and look for patterns and trends. Use tools like Pareto charts, fishbone diagrams, and 5 whys to identify the most significant factors that contribute to defects and rework.
  • Generate and implement solutions to address the root causes of defects and rework. Use tools like brainstorming, benchmarking, and pilot testing to come up with effective and feasible solutions.
  • Monitor and evaluate the results of your solutions and measure the improvement in your FPY and RTY. Use tools like control charts, dashboards, and audits to track and sustain your process performance.

Summary:

RTY calculation is a powerful tool that can help you measure and improve your process efficiency. By calculating the RTY of your process, you can identify the sources of waste and rework and take action to eliminate them. This will result in higher quality, lower cost, and faster delivery of your products and services.