How Mixers Can Help Improve the Quality and Efficiency of Production
In an ever-increasing competitive landscape, manufacturing companies are always looking for ways to increase the efficiency of their production and the quality of their products. The coatings industry is no exception. The choice of mixing technology while developing new coatings and when scaling up production is an important consideration to help ensure the best products are produced in the most economical way.
PCI recently asked Christine Banaszek, a Sales Manager at Charles Ross & Son Co., how mixers can help manufacturers to improve the efficiency and quality of their coatings. Established in 1842, Charles Ross & Son Co. is an employee-owned company with a reputation for innovative engineering and excellent construction. The company provides mixing, blending, drying and dispersion equipment that is available in standard and custom designs, working to meet customers’ specific processing needs. Ross serves industries that include the chemical, coatings, pharmaceutical, cosmetics, adhesives, plastics and food industries, among others.
PCI: What is an aspect of mixing technology that manufacturers should be paying more attention to?
Banaszek: In the product development stage, manufacturers need to ensure that their lab or pilot plant employs mixing technologies that are truly scalable. While the choices for laboratory mixers are many – from simple magnetic stirrers, kitchen-style blenders and overhead mixers to more expensive glass reactors – not all are easily scaled to production volumes. Since many mixtures obtain characteristics that are process-sensitive, the proper mixing equipment must be identified at the R&D level. Without a practical path to scale-up, results produced in the lab cannot be replicated in a cost-effective manner.
PCI: How can poor decisions about new mixing technology impact efficiency of operation and quality outcomes?
Banaszek: Poor choice of a mixing strategy, or even selecting the right type of mixer but failing to include critical customizations, can become a costly mistake in the long run. Consequences include longer cycle times, labor-intensive processing and cleaning, batch-to-batch inconsistencies, contamination, frequent reworks, and expensive maintenance.
PCI: What are the trends in automation that can help improve quality outcomes?
Banaszek: More and more manufacturers are investing in PLC-based controls with automated recipe system for key process variables (speed, time, temperature, vacuum level, etc.). Automating the mixing operation lessens operator errors, which leads to more predictable and repeatable quality. It offers many other important benefits including better monitoring and recordkeeping; improved safety; faster changeovers; and lower overall cost of production due to less labor, less waste and less energy consumption.
PCI: How are new technologies helping to reduce the amount of scrap product generated from manufacturing operations related to mixing?
Banaszek: Waste and delays attributed to frequent rework or scrapping of a bad batch may be resolved by reviewing each step of the mixing process including method and order of ingredient addition. There are new and evolving technologies for rapid sub-surface powder dispersion, high-speed mixing of viscous mixtures, vacuum blending/drying, ultra-high shear emulsification, etc. Mixing is a very application-dependent operation, which is why actual testing is often a prerequisite in identifying the most practical solution to a particular inefficient operation. In exploring unfamiliar technologies, take advantage of mixer trials/demo runs or rental programs.
PCI: What are some examples of how mixers have made a manufacturing process more efficient?
Banaszek: In the manufacture of paints and coatings, ultra-high-shear mixing of dry pigment powders into the liquid vehicle has eliminated the need for downstream milling in some instances, eliminated clogging and accelerated media milling in others. Hybrid planetary dispersers have enabled "one-pot processing" of various viscous formulations that previously required a double planetary mixer to process the concentrate or masterbatch, followed by a let-down step in a different type of mixer, typically a dissolver.
PCI: In manufacturing, correct measurement is essential for quality outcomes. Are there recent improvements in measurement technology and methods that can help to improve quality and efficiency?
Banaszek: One example is a multi-shaft mixer supplied with a recirculation line equipped with viscosity and density transmitters to quickly verify that the batch has reached the end point and is within spec. (See photo.)