Time studies at a manufacturer of energy storage devices

Project period: February 2016 - March 2016,
Germany, North Rhine-Westphalia
Consultants involved: 1

Initial situation

The company assembles energy storage systems at its plant in NRW. In particular, the energy storage system XY is entirely assembled there. The assembly times have increased in the past, which has had a negative impact on the cost structure or the manufacturing costs of the product.

The profit margin of the product moved towards 0.

Aim of the REFA counselling

The aim of the project was to determine the scheduled times (basic times) and the unscheduled times (Waste) and to make suggestions for reducing assembly times . A sustainable reduction in manufacturing costs via reduced assembly times was the principal aim.

REFA approach

The work order time for the person T requires the presence of setup times and execution times or the time per unit.

The object of the time studies are the basic times. All unscheduled times (factual allowance time) are recorded as part of the time studies. The unscheduled times are used to identify anomalies that could include possibilities to improve the process organisation.

Procedure in the specific project

Conducting time studies during the manufacturing of the product at the factory in NRW. For this purpose, all necessary work contents of the

• assembly of the mechanical parts,
• assembly of the electrical/electronic parts,
• prefabrication as well as the
• activities to make the product ready for shipment

had to be registered.

Within the framework of the time studies, not only the scheduled and unscheduled times had to be recorded, but also the non- value-adding activities (travelling times, provision of materials, waiting times, etc.).

The processes were ultimately assessed in terms of how and where the extent of manufacturing could be reduced.

1. Preparation of the time studies/process studies

• Coordination with existing descriptions of the work progressions and determination of the process sections and measuring points.
• The types of time to be recorded for persons’ activities were determined.
• Briefing by our REFA consultant on the detailed process and specification of the processes and occupational safety.
• The study frameworks for data collection (time studies) were created.
• The employees were informed about the objectives and the implementation of the data collection.   

2. Implementation the time studies

The time studies were carried out and evaluated by a consultant from REFA Consulting AG using the software solution REFA Time.

3. Results of this consulting project “Time study”

• Complete and reproducible documentation of all determined data, assigned to the processes
• Evaluation of all time fractions (reproducible) according to the REFA methodology and according to the operational requirements
• Thematic list with observed anomalies and wastes
• Proposals for increasing the value creation and thus reducing the allowed time for the complete assembly

The savings volume through the REFA time study was 21 % of the manufacturing costs, which reduced the assembly costs by 219,000 euros per annum.