Takt in manufacturing – production that doesn’t miss a beat
26 September 2017
The humble drumkit is the cornerstone of modern music and is responsible for keeping pace, giving listeners precisely the song they want. Interestingly, the principles of musical timekeeping have contributed to one of manufacturing’s most important lean measurements — takt time.
Takt time is a way of measuring the rate of production in line with customer demand. The phrase was likely introduced to Japan by German engineers in the 1930s and takes its name from the German word Taktzeit, which translates to ‘clock interval’ (it has its roots in musical measures). The concept is critical for lean manufacturers to directly meet the expectations of the market.
Takt time is mostly calculated for production lines, but it can be implemented across every task in a business environment, from manufacturing and operations to control tasks and administration. Yet despite its importance, many plant managers misunderstand the essence of the idea and fall behind on production.
This often comes down to an error of measurement and terminology. While the endgame is to perfectly align the rate of production with takt time, many plant managers believe that takt time is related to the time it takes to make the product.
taktThis leads to the misconception that managers think of takt in terms of production cycle times and shifts. However, depending on the business, these measurements are inaccurate and result in ineffective production rates.
Shift-mentality, for example, assumes that the rate of customer demand will be steady and unchanging. Yet this is not the case in industries such as the food sector, which requires manufacturers to be ready to meet the rapidly changing demands of the market at any time.
For example, food manufacturers will often need to change recipes and branding to align them with seasonal events, such as pumpkin-based product variants in Autumnal months. This requires the manufacturer to ensure that lead times are kept to a minimal, allowing production to adhere closely to the takt time.
Adjusting takt time to each company’s requirements
In reality, people and any machinery in a production line cannot maintain 100 per cent efficiency and stoppages can occur. In these instances, managers must think more in terms of smaller, more specific blocks of time and adjust takt time to fit within the requirements of a company.
For example, if there is one department which delivers parts to multiple manufacturing lines, managers should consider using similar takt times across all lines, to keep the flow from the preceding station controlled. This may result in certain hours of the day where takt time is higher than others, similar to that of a restaurant catering for elevated demand during evening hours.
Similarly, implementing a takt system enables managers to easily identify issues in the production line that could hinder production. This is because, as the line moves a long, stations requiring longer times will become apparent almost immediately. Managers can then adjust production times accordingly to optimise production.
Arguably the most important thing to bear in mind is the distinction between cycle time and takt time. It is almost inevitable for some cycles, irrespective of how lean the management of the plant is, to contain waste. Unless this is also taken into consideration, the process will eventually result in a shortfall of customer demand.
For example, a manufacturing facility that requires a recently produced part to be transported from one line to another will find that waste occurs during this process. This could be due to the ease of manually handling the product or, depending on the size and quantity of the parts, the availability of factory forklifts.
In this instance, the cycle time matching the takt time would still result in under-production. Instead, managers should seek to make production cycles and the average waste per cycle total the takt time. Once this is in place and production is in line with demand, managers can then go about reducing the waste per cycle.
This is achieved by determining what each process is capable of, from the speeds of the machines to the number of people needed to produce a single batch or product. Takt time only permits a certain amount of time to perform the actual value-added work, which assists manufacturers in being able to eliminate all non-value added tasks to optimise their production lines.
Allocate time for instances of downtime
With takt time, plant managers can pace production so that the customer demand is level across the time it chooses to produce. Practically applied, takt time will specifically allocate time for any instances of planned and unplanned downtime, so that plant managers can compensate any shortfall in production.
This is one of the less obvious benefits of takt time. By fully assessing the production process and identifying these areas of waste, plant managers can subsequently improve efficiency in those specific areas. This is because takt times create a beat, or flow, to a company’s processes so that issues with quality, capacity and synchronisation become more apparent.
In situations where staff have to manually handle waste because of a lack of forklift availability, plant managers should invest in pedestrian-operated industrial handling equipment, such as a motorised electric tug like MasterMover’s MasterTug. This allows staff to easily move heavy objects or large quantities of product from one line to another efficiently and without waste.
This is just one example of how businesses can reduce the number of non-value-added tasks in their production line.
It is fundamental that plant managers think of takt time as a tool to ensure that all of their plant capacity is utilised, so that, with detailed planning, customer demand is met. It is therefore not merely a metric of time but a new and practical way of running operations.
Just as a musical composer would not keep all but one instrument in time with the drum beat, plant managers must consider all aspects of a production cycle when determining takt time. By accounting for waste and anticipated shifts in customer demand, managers can ensure that their production never misses a beat.
Andy Owen, managing director of motorised electric tug specialist MasterMover