Business case
- A multinational pharmaceutical company struggled with a highly automated continuous mixer which was designed to produce 4000 kg/hr of paste.
- Excess inventory and WIP was being stored in bulk tanks
- The plant runs seven days per week and feeds a number of high speed packing lines each running at up to 500 units per minute.
Initial Condition
- The mixing plant running at significantly less than 4000 kgs/hr,
- Many short stops (eight to ten per hour) and re-starts of the line per shift—due to breakdown and loss of raw material feed.
- If an operator is not available for immediate re-set, the plant could be left at a standstill for up to 20 minutes.
- For 90 days prior to intervention, overall output averaged only 2200 kgs/hr with an OEE of less than 50%.
Target Condition
- Increase daily output to 4000kgs/hr as required to meet process and production goals
- Eliminate hourly stops and re-starts of line
- Return product quality to previous levels
Planned Activities / Intervention
- The team used PCS- problem solving model to find root causes for the large number of stoppages associated with the powder feed (raw material) systems.
- A team was put together including experienced plant operators, technicians and area management to work on these problems. A number of Problem Cause Solution (PCS) exercises were carried out to find the root causes.
- Root causes determined included:
- Control system settings not optimized
- Feed systems unable to run at the desired maximum speed
- Bulk density variations
- Line blockages caused by valve timings not being optimally set
- Countermeasures put in place to eliminate all of the above issues, along with skills upgrade for operators and sustainment plan
Achieved Metrics
- OEE of the continuous flow line increased by 38%.
- Running hours dropped by 200 hours to meet annual production plan
- Average number of stoppage alarms dropped from an average of 8-10 per hour to less than 2
- The problem-solving model is now available as a detailed guide in case further problems arise in future (knowledge transfer).
