Why lean production?
Our main target is reducing waste (time is a major waste) in the production and better (faster) serve our customers.
The first step – “clear the clouds”
We first needed to learn to see the real nature of our production processes. We learn to look through “lean glasses” to recognise the biggest waste items in our process. Waste can be waiting times between different processes, or stability problems in the process that create flow breakdowns.
Second step – list and analyse problems, set priorities
We formed a brainstorming team with colleagues from all areas in the company. The purpose of the sessions is to identify these areas in our process where we find important waste that can be cleared rather fast. We use Ishikawa root cause analysis for this.
During the brainstorming sessions we identified four areas where we think we can improve rapidly:
- Mechanical department
- Galvanic lines
- define KPI”s ( Key performance indicators)
- Priority settings
Creating a smooth production flow
When we have waves in our production this creates “traffic jams”. These jams are the main reason for delay. The best way to guarantee on-time delivery is by creating a smooth production flow. For that we need stable processes, a well balanced capacity distribution throughout the process, and skilled operators.
PCB production is a complicated process with a lot of different steps. Each order can be following a slightly different flow as different options are chosen. That makes is challenging to create a smooth flow. Most energy is spend in organizing the “human factor” – monitoring and motivating operators to think and act lean. Training is organised continually, and we try to involve people from all levels and all departments in the project.
New KPI”s (key performance indicators)
Existing KPI”s in the organisation are evaluated for their usefulness and following new KPI”s are introduced because we think they can inform us about our progress in this lean project.
- KPI for measuring the average throughput time (in hours)
- KPI”s measuring the efficiency in the galvanic process
- KPI for measuring the efficiency in the drilling department.
Beginning of October 2011 we started experimenting with a FIFO based system for setting priorities in each step of the production from the Blackhole PTH till the Soldermask curing step. As the first results are good we are now organizing to extend the reach of this FIFO method to the whole process of double sided production.
Controlled and decreased WIP (Work in Process)
We decreased and started to control the inventory of panels in production. Inventory is allowed only in clearly defined locations and up to a defined maximum number of panels. We produce in smaller lots based on the capacity of our bottleneck, the galvanic line. Jobs are started only for production when there is capacity available.
Panels waiting before the galvanic process before introduction of the WIP inventory control
Panels before the galvanic process with controlled inventory
As we are gaining more experience in the lean project, our confidence is growing that we can further increase efficiency and reliability. The knowledge built in the factory in Eger, Hungary will be useful when we start a new production unit in Gandhinagar India in 2012 to serve the Asian market with prototype pcb”s.