What is Lean Manufacturing?

(Tiwari and Wanjari, 2010)

As per Kilpatrick (1997), lean manufacturing increases capacity, quality, and productivity while reducing inventory and lead time(s). Several features of Lean techniques were first introduced at the Ford production plants in the 1920s. This was mentioned in the books ‘My life and work’ and ‘Today and tomorrow’, written by Henry Ford himself. According to Ford, focus on functions which add value to customer while reducing material, time and motion wastages.

The book “The Machine that Changed the World” describes about the Toyota Production System and the term “Lean production” was firstly appeared. Lean approach allowed Japanese companies to reduce the cost and increase the quality (Korchagin, Deniskina, and Fateeva , 2019).

Korchagin et al. (2018) stated that the efficiency of lean process is based on the eliminating unnecessary activities or in other words wastes in the manufacturing process. This would save cost and optimize the production cost and resources.

Korchagin, Deniskina, and Fateeva (2019) identifies following types of Wastes

1. Wastes due to overproduction (Eg: Manufacturing more than the demand or what is required for the next stage of the process)
2. Time waste due to waiting (Eg: short breaks in between working hours; waiting for people, materials, equipment etc)
3. Wastes due to excessive processing (Eg: due to tool’s poor quality, design mistakes etc.)
4. Wastes due to unnecessary movements (Eg: movement of people, tools or equipment that does not add value to the final product)
5. Wastes due to inventory (Eg: high stock level of raw materials or finished product)
6. Wastes during transportation (Eg: Unnecessary long distance transportation of materials etc.)
7. Wastes due to the release of defective products (Eg: Additional inspection, replacement etc.)

Following Lean manufacturing techniques, which could be used to reduce or eliminate wastages.

1. Cellular manufacturing

Organizes the entire process into a group (or “cell”), including all the necessary machines, equipment and operators to facilitate small lot, continuous flow production.

(AMIA systems, 2017) 

2. Just-in-time (JIT)

JIT is an inventory system that minimizes inventory by aligning raw-material orders directly with production schedules.

3. Kanbans: A signalling system or scheduling system for JIT production.

4. Total preventive maintenance (TPM): Preventing breakdowns rather than fixing.

5. Setup time reduction: Continuously reducing the machine setup time.

6. Total quality management (TQM): TQM is a continual process of detecting and reducing or eliminating errors in manufacturing. Key components are employee involvement and training, problem-solving etc.

References;
Ford H. (1922) My life and work. New York: Garden City.

Ford, H. (1926) Today and tomorrow. New York: Doubleday.

Kilpatrick, A. (1997) Lean manufacturing principles: a comprehensive framework for improving production efficiency. MSc Thesis. Massachusetts Institute of Technology.

Korchagin, A., Deniskina, A. and Fateeva, I. (2019) ‘Lean and energy efficient production based on internet of things (IOT) in aviation industry’, E3S Web of Conferences, 110, pp. 1-13.

AMIA systems (2017), What is Cellular Manufacturing?. Available at: https://www.amia-systems.com/what-is-cellular-manufacturing/ (Accessed 15 Dec. 2019).

Tiwari, A. and Wanjari, S. (2010), Lean Manufacturing In Apparel Industry. Available at: https://www.fibre2fashion.com/industry-article/5159/lean-manufacturing-in-apparel-industr (Accessed 15 Dec. 2019).