Lean concepts timing

Later in this chapter, comments are made on a catastrophe in which the management acknowledged in its own internally prepared report that its safety culture, over time, had been allowed to deteriorate. In Chapter 14, Lean Concepts Opportunities for Safety Professionals, reference is made to safety levels being diminished as lean concepts are applied. In discussions with several safety directors, it has been readily established that everyone is expected to do more with less and that bottom-line pressures weigh heavily. 

Applying lean concepts to eliminate waste, improve efficiency, and lower production costs has become popular with senior-level managements. Minimizing waste is the foundation on which the lean concept is built. In a lean endeavor, activities or processes that consume resources, add cost, or require unproductive time without creating value are eliminated. The lean concept can be described as striving for excellence in operations in which each employee seeks to eliminate waste and participates in the smooth flow of value to the customer. 

Value Stream Mapping is the written or computer-based identification of the sequence of activities and information flows to produce a product or deliver a service. This represents a vital step in the lean concept because it provides the opportunity for team brainstorming to identify activities that do not add value. Lean practitioners use value stream mapping to identify major sources of non-value-added time in a value stream envision a less wasteful future state and develop an implementation plan for future lean activities. An Addendum providing a Simplified Initial Value Stream Map appears at the end of this chapter. 

The more popular concepts of lean operations tend to be the concepts of muda, flow and pull system. A preliminary analysis of all these methods, as we have described earlier, however, highlights the fact that all assume sufficient machine availability exists as a prerequisite. In our experience for many companies attempting a lean transformation this assumption is not true. Machine availability depends on maximizing the machine up time by eliminating the root causes of down time. The ratio of up time and planned operation time is the efficiency of the operation. Therefore, in order to make lean concepts work it is vital that the pre-condition of running the operations at a high level of efficiency should be met. The old approach of measuring labour efficiency (e.g. the ratio of standard hours and hours worked) has now shifted to the efficiency of the control or bottleneck workstation. 

An alternate to the concept of cluster renewal discussed above is the concept of two-phase convection. This second approach disregards the separate behavior of lean and dense phases, instead models the time average heat transfer process as if it were convective from a pseudo-homogeneous particle-gas medium. Thus h hcl, hh and hd are not... 

Nearly a century later, Frederick W. Taylor introduced the concepts of time study and standardized work, coining the term scientific management. It was not until 1908, with Henry Ford s introduction of the Model T, that the value of lean manufacturing was recognized worldwide. Henry Ford is considered by some to be the first practi-... 

New Concept of Waste-Gas Capture during Viscose Staple Fiber Production. As a result of the basic chemical reactions in a sulfuric acid plant and the desired conversion of nearly 100%, the ratio of the quantity of combustion air to sulfur is fixed. If the entire amount of waste gas formed in a conventional viscose staple fiber plant were to be used as combustion air in a sulfuric acid plant, about 30 times as much sulfuric acid would have to be produced as the staple fiber plant consumes. The quantity of lean waste gas from the viscose plant must therefore first be matched to the much lower combustion air requirement of the sulfuric acid plant. This can be achieved by appropriate reduction of the air exhaustion in the viscose staple fiber plant. However, this is possible only if, at the same time, risks to safety as a result of exceeding the in-plant threshold limit value and of the occurrence of explosive gas-air mixtures are avoided. 

Many companies undertake training of employees in the concepts and tools shown in Table 24.1. Much of this time is wasted without application to a process improvement effort. Supply chain improvement efforts are a good way to introduce Design Team members to process documentation as part of lean. Six Sigma, Total Quality initiatives, or unlabeled efforts. Process documentation and analysis skill is the core competency for these initiatives. 

The implementation of lean manufacturing, just-in-time, and quick response concepts caused large manufacturing firms to be seen as too diversified and inflexible to operate efficiently on a dynamically changing market. The management of many companies concluded that... 

In summary, the researchers have applied the concepts above, by focusing on the concepts of Ohno (1998), Hudson et al. (2001), Wilson et al. (2008), and Nasser Mohd et al. (2009) to specify the criteria for performance measurement related to lean manufacmring, and in all twenty-four variables under all the five performance measurement perspectives (quality, time, finance, customer satisfaction, and human resources) as follows ... 

When work on a critical path stops because resources are busy elsewhere or critical resources are idle, the cause is likely to be in poor scheduling. The critical path keeps shifting because of the uncertainty of project work. Goldratt (1999) with his Critical Chain and theory of constraints pointed out that the calculation of floats can be misleading. The apparent buffer of time can evaporate due to preset times and allocation of resources. Building upon the concept of Critical Chain lean project management developed, and it comprises three major activities ... 

---