Good, better, asphalt production

Even good practices can be improved. Lemminkäinen’s asphalt production costs in Latvia were already competitive to begin with, but a Lean Six Sigma (LSS) project was given the bold target of further improving competitiveness.

The project resulted in an even more effective production process, along with cost savings and a more environmentally friendly asphalt product.

We set up a team of production employees to implement the project. We rolled up our sleeves and started by identifying as many factors affecting asphalt production costs as possible. When that was done, we proceeded to analyse the information.

“Assumptions should be tested by examining actual figures, as collecting accurate data is the key to success. Only then do the facts begin to shine through,” says Aivis Putniņš, Asphalt Plant Manager at Lemminkäinen.

“We found out that moisture content affects production costs the most. Our team soon realised that we could generate substantial savings by using more recycled mineral aggregates,” says Production Quality Engineer Jānis Oga.

New recipe brings environmental benefits

The asphalt recipe was modified to allow us to use more recycled material in production. This increased the use of recycled mineral aggregates in asphalt production by 15 per cent while also reducing the environmental impact.

“We further elaborated on our objective when planning production cost cuts, opting for reducing the use of natural gas. The significant factors affecting gas consumption included the moisture content of mineral aggregates and the calibration of the drying drum burner,” Putniņš explains.

By autumn, asphalt production was at full speed. “The LSS project has helped us achieve significant savings,” Jānis says, adding that the most important thing is to engage as many team members as possible in the reform. “The desired outcome is easier to achieve when everybody knows the objective of and reasons for the changes.”

What is Lean Six Sigma?

  • Six Sigma is a systematic way of working based on statistical methods to reduce process errors and deviations.
  • Lean focuses on streamlining processes to reduce unnecessary work and the amount of tied-up capital.
  • Lean Six Sigma is a way of thinking that combines the best aspects of these two approaches.
  • We have successfully applied Lean Six Sigma thinking to many development projects in various businesses