Since 1982 – Reliability in Every Batch
Case Study: Upgrading Color
Mixing Technology for Rotational Molding
Background
A rotational molding plant specializing in underground enclosures for waterworks and irrigation was facing severe color irregularities in its molded components. Their existing line of mixers had been foraged from their bone yard and procured from used equipment dealers.
Original Mixers
- Manufactured by: Unknown in most cases.
- Mixing capacity: 8,000–10,000 lbs per day with a 12-hour shift.
- Mixer Design: Drum Mixers and Cement Mixers (Home Depot)
- Issues observed:
- Inconsistent dispersion of pigments
- Streaking in final molded product
- Long Cleanouts
- Multiple Mixing Operators running multiple mixers
Motivation for Changeout
- Loss of Customers
- Reduction of Costs
- Demand for higher thruput
- Source for support
New Rotational Molding Mixer
- Manufactured By: Reliance Industries, Inc.
- Mixer capacity: 300 lbs per batch @ 7 batches per hour.
- Mixer Design: High Intensity Mixer for Rotational Molding Application
- Key features:
- Fluidizing Material
- Fast Mixing Times
- Homogenized Mix with complete dispersion of pigment
. Changeout Process
- Preparation: New Mixer is setup and all required air and electrical brought into area.
- Installation: Mixer stand placed and anchored in place. Mixer installed on stand and all electrical and pneumatics plumbed to mixer.
- Integration: Control panel was supplied mounted on mixer, so 460V power was supplied to the panel and pneumatics were connected to the air port on the mixer.
Results and Performance Comparison
Metric | Original Capacity | New Capacity |
---|---|---|
Throughput capacity | 8–10K lbs in 12-hour shift | 14K lbs in 8-hour shift |
Scrap due to mixing | 5–7% | 0% |
Benefits Achieved
- Production increase: 40% Increase in 66% of the original time.
- Support: Startup assistance supplied along with technical support
- Labor: Customer was able to reduce shift time by 4 hrs and cut labor by 50%.
Conclusion
The changeout from the original mixing process to a Reliance Rotational Molding Mixer provided improvements in efficiency, repeatability, and cost savings. High speed mixer blades coupled with a Vertical Bowl/Pot design allowed for fast repeatable mixing with quality improvement. Labor and Man hours were drastically reduced and scrap from Mixing came down to 0%.

