Using Lean Manufacturing Tools

Read this article. It highlights the importance, in a global competition environment, of measuring and analyzing lean manufacturing processes.

1. Introduction

The improvement initiative arose when it became clear that production capacity for the front and rear M300 wheel hub needed to increase in order to meet increased demand in Ecuador and Colombia. It is a business that holds potential to deal with SOFASA and General Motors, which required high production volumes compared with the current ones.

At the same time, General Motors demands that "lean manufacturing" be applied as a way of both increasing productivity and ensuring high quality. The goal is to make continuous improvement processes more robust.

These strategies must be applied to the manufacture of the front and rear M300 wheel hub supplied to General Motors.

The plant is divided into two main areas: forging and machining.

  1. Forge area: The smelting process is carried out under heat. In this area, the forging process is a closed one where the material is formed by applying compression forces. The steel is shaped by pressing it between two blocks (closed matrix) while raising the temperature in industrial furnaces. The furnaces work in the same cell as the corresponding presses. A normalization process and checking for cracks also takes place in this area.

  2. Machining area: here chip removal operations are preformed that result in semi-finished products through roughing (which require subsequent processes), or finished products with their final diameter (finishing processes).

Table 1 shows the machines and the manufacturing process for each area of the plant.

There are currently 14 operators working at the plant:

  • Production capacity: The average real maximum production of M300 wheel hubs was 3000 units during the last half of 2017. Taking stock of performance flaws revealed that there was no record of machine stoppages or other short-comings in the process, and no standardized time tests to identify the maximum installed capacity of the plant along with bottle necks. This implies that no corrective planning and production programming is done leading to cost over-runs, delays, and all kinds of waste.

  • Time studies: In order to define the initial productivity level, a time study was done to find the standard time and number of pieces produced per hour in each operation. This can also be seen in Table 1.