The drum is scheduled to deliver in the same sequence as the market demand. Only the drum is scheduled to make maximum use of its available capacity. All other machines have to work in such a way that the drum never runs out of work and the drum schedule is not disrupted.

This means more set ups and lower machine efficiencies on non-drum machines. Even though it appears that the non-drum machines are not utilised fully and some of them are idle from time to time, this is encouraged. This is contrary to the traditional way of working but is actually good for the plant as a whole.

Another important point is to recognise the fact that Murphy exists. Murphy’s Law states that if anything has to go wrong, it will at the worst possible time. In simpler terms, it means that there are always bound to be some interruptions, or unexpected deviations, in our planned activities. Absenteeism, late deliveries by suppliers, quality problems etc. are some commonly known examples of Murphy.

Buffers (time buffers or stock buffers) are introduced before the drum in order to protect its schedule from Murphy. Inventory is not allowed to accumulate anywhere else, thus reducing WIP and ensuring faster processing times.

This way, even if there are interruptions due to bad quality, absenteeism, breakdowns etc., the drum schedule does not suffer. Therefore, we get the maximum money out of the drum, and hence the maximum money out of the plant.

This ensures that the plant works only on the material for which there is a firm market demand. Consequently, it has better ability to deliver on time and is able to adjust to a changing market demand more quickly.

The buffer manger monitors the extent of buffer depletion. When the penetration is up to 33%, no expediting is needed. When the penetration is between 33% and 66%, a plan for expediting is made, however, no expediting actually takes place. Expediting is done, i.e. the action plan is put in to practice, only after the penetration is more than 66%.

This greatly reduces the need for fire fighting. Moreover, it ensures that a plan for expediting is already in place before the delay actually occurs. Thus, the expediting under this scheme is more effective than traditional fire fighting.

Buffers also play an important role in focusing on the areas where improvements will bring maximum benefits to the company. Any buffer depletion means that something did not work as planned. All causes of buffer depletions are carefully investigated to determine the root cause. Elimination/minimization of the root cause ensures that the system is now improved and therefore, is having better reliability and lesser lead-time. These effects are highly desirable. About 50% of the benefits of adopting a DBR come from good buffer management alone.

The Rope ties the material release to the actual market demand. Thus, only that material is released in to the system for which there is a firm order. The sequence of the drum schedule determines the sequence and timing of material release. Forecast orders are reduced to zero.

Using the improvements in on time delivery and total manufacturing time, a better marketing strategy can be used to have further increase in demand and hence more profits.

• On time deliveries will potentially improve to the tune of 95 - 98%.
• Inventory can potentially reduce to 30-40%.
• 20-25% capacity can be potentially revealed. This can be converted to increase in throughput if there is a good order book on hand.
• Provide a system that will give common priorities to all resources in line with satisfying the customer.
• Provide a system to monitor progress and take corrective actions proactively.
• Provide a system of ongoing improvements to focus the improvement efforts.
• Provide right financial, operational and shop floor measurements in line with achieving system goal.
• The team's morale and effectiveness will improve because they will be operating in an environment that is comfortable with uncertainty and that avoids micro management.
• Senior management time will be freed up for more developmental activities rather than fire fighting activities.