Pain Multiplies When Processes Connect

Pain Multiplies When Processes Connect

Organizations unlock tremendous waste by focusing on the flow of value in delivering their product or service. The velocity of the value stream that delivers the product or service is directly tied to the flow of the process. Queues, buffers, and staging points slow the velocity and increase the cost … BUT, there is risk that comes with connecting all processes and not accumulating any product between them.

The Compounding Effect of Delays on Connected Processes

Suppose a business has automated the process of washing crates used for transporting produce. The process starts with unstacking the crates, opening the crates, washing the crates, drying the crates, and restacking them. The wonders of modern automation allow the process to be linked and coordinated with sophisticated Programmable Logic Controls (plc’s). Conveyors transfer the crates quickly from process to process. Tremendous value is created as one by one the crates are washed at a pace of 4,000 per hour.

The challenge for the leader of such a process is to continue the flow, uninterrupted, every hour and wash 4,000 crates. With good daily management and effective problem solving it will be possible, but in the early stages jams and delays will plague the process while the demand for 4,000 crates an hour will remain. One countermeasure to maintain flow is the use of safety stock within the process.

Buffer the Impact of Minor Delays with Safety Stock

The challenge of processes linked together is the compounded effect of delays. If the first process of unstacking the crates is able to flawlessly unstack 95% of the crates, then 3,800 crates will make it to the process of opening the crates. If opening the crates is 95% successful, then 3,610 of the 3,800 crates will make it to washing. If washing is 95% successful, then 3,429 crates will make it through washing and so on.

In the end, with just these 3 initial processes, the goal of 4,000 crates will result in 3,429 crates if each of the first three process achieves 95% success.

Interestingly if each process were 99% successful, it would still miss the mark with 3,881 crates instead of 4,000.

The good news, however, is that there is an effective countermeasure. If we allow for the accumulation of crates between the processes to effectively absorb the minor delays, we can maintain a flow 4,000 an hour.

Suppose we set up a plc that will introduce a crate that is already unstacked to the system is one is delayed. Likewise, we can introduce an opened crate to the flow if the process of opening is jammed, and finally we can add washed crates from an inventory of washed crates if the washer has a jam.

This strategy requires that we have built entry points into the process for these crates with completed steps and it requires that we build up the inventory at the end of the shift to allow for the next run.

The Hidden Beauty is in the Clarity of the Cost of the Problem

The goal of connected processes and flow is to remove the barriers to flow and increase the reliability of each process. As said, this is done with good daily management and problem solving. But the beauty of the safety stock in the process is that it can be measured and reduced over time. What may start out as 200 crates can have a reasonable goal of maintaining flow with only 50 crates.

Help your organization recognize the compounding effect of connected processes and build stock to maintain the flow of your product or service.

Learn more in Patrick’s book, “Facilitating Effective Change,” available online through Amazon and Barnes & Noble.