Since 1842, Charles Ross and Son Company has been developing and manufacturing industrial mixing, blending, drying, and dispersion equipment. Flip through the timeline below to see how Ross has been at the forefront of mixing technology over the years.
Two young brothers, John, a baker and Charles, a mechanic, become partners in two businesses, side by side in a small building in Rochester, New York. The Ross brothers operate a bakery and build grain mills. They prosper for 20 years until the Civil War divides the brothers. Years later, Charles returns to the shop. John lays buried on a hillside in Virginia.
Charles G. Ross moves the factory to another part of Brooklyn which was fast becoming a paint center in those days. Ross designs and builds mills for nearby thriving paint companies. The chemical and pharmaceutical also become extensive markets for mills and mixers. Stimulated by the growing automobile industry, producers of lubricants and greases purchase Ross stone mills. The better facilities of the new plant allow Charles Ross & Son Company to serve the growing demand and gather enough momentum to carry them through the 1903 recession and 1907 banking crisis.
Ross introduces the world's first change-can Double Planetary Mixer which quickly becomes a popular machine for batching heavy paste paints. It had two sets of prong-like stirrers that rotated on individual axes while revolving around the vessel interior. All the gearing and other moving parts were enclosed in cast iron housings and operated in a continuous oil bath. During mixing, the vessel was fully covered but the operator could view the internals from a lamp-lit inspection window. When the batch is complete, a hydraulic lift raised the driving components and stirrers from the mix can. As the finished product is discharged, another vessel could be placed under the mixer to start a new batch.
Ross moves to Hauppauge, a town on Long Island, New York. The headquarters consisted of administrative and engineering offices, a manufacturing shop and soon after a testing lab where customers could test Ross mixers and blenders prior to purchase. The lab has expanded numerous times in the following decades. Today, the Ross Test & Development Center is the most equipped testing facility in the specialty mixing industry. A typical mixing simulation test utilizes the end user's actual raw materials and the mixer is operated at process conditions as close as possible to actual production. Proof-of-concept demonstrations such as high shear emulsification, particle size reduction, dry blending, vacuum drying, high viscosity mixing and three roll milling are performed routinely.
Ross patents a hybrid planetary mixer design equipped with both low and high speed agitators, accomplishing mixing tasks normally done by two or more devices. The novel configuration features a stirrer blade that rotates on its own axis while orbiting the mix vessel, delivering a thorough mixing and kneading action suitable for processing high viscosity mixtures. At the same time, a saw-tooth disperser blade also revolves around the batch while turning on its own axis at tip speeds of around 5,000 ft/min. This high speed blade quickly disperses powders, fibers, pellets and other solids regardless of product rheology. Each agitator is controlled independently allowing the operator to fine-tune flow patterns and shear rates at any point during the mixing cycle. Today, the PowerMix Planetary Disperser is an indispensable tool for hundreds of users in the adhesives, chemical, plastics, composites, coatings, medical and other industries.
James C. Ross, son of Richard Ross, invents the X-Series Inline Ultra-High Shear Mixer, a quantum leap in rotor/stator technology. Turning at tip speeds over 11,000 ft/min, the X-Series rotor consists of concentric rows of intermeshing teeth. Product enters from the center of the stator and moves outward through radial channels in the rotor/stator teeth. The combination of high tip speed and extremely close tolerances between the interlocking channels subjects the product to intense shear in every pass. Adjustable gap settings allow for fine-tuning of shear level and flow rate. The X-Series patent is granted in 1997 and in process lines around the world, the invention readily demonstrates a distinct ability to produce submicron dispersions and emulsions superior to those made in multi-stage rotor/stators and colloid mills. In certain applications, X-Series Mixers replace high pressure homogenizers, delivering comparable size reduction at significantly higher throughputs.
The company's technical services group completes the development a novel powder induction technology called SLIM which stands for Solids/Liquid Injection Manifold. The SLIM is the most efficient and reliable device available in the market today for dispersing powders into a liquid. It features a specially engineered rotor that creates an intense vacuum which draws solids into the high shear zone of the mix chamber. Challenging powders like fumed silica, gums, thickeners and pigments are dispersed instantly. Proven on process lines around the world, the SLIM routinely cuts process times by 80% or more, eliminating issues like excessive dusting, floating powders, persistent lumps or "fish eyes" and wasted raw materials due to inefficient dispersion.
Ross is granted the patent for the "Delta" rotor/stator of its PreMax Batch Ultra-High Shear Mixer. The Delta rotor runs at higher tip speeds (5,000 ft/min) than a regular high-shear mixer device, creating enhanced levels of mechanical, hydraulic and cavitational shear. In addition, the Delta rotor's unique shape generates a double vortex and intense vigorous flow which quickly draws powders from the batch surface. For most inks and coating applications, the level of pigment dispersion achieved in the PreMax is comparable to one or two passes through a media mill.
Ross receives another patent for the development of "High Viscosity" (HV) Blades, now the prevalent stirrer design used in Ross Double Planetary Mixers. Featuring a precisely angled helical contour, HV Blades generate a forward and downward mixing action, keeping product within the vessel at all times and preventing the climbing problem sometimes experienced with traditional rectangular stirrers. The HV Blades extend the Double Planetary Mixer's viscosity range to approximately 6 million centipoise, easily handling applications that previously required a more expensive horizontal sigma blade kneader. The rotating helical stirrers pass each other in a slicing motion, which more evenly distributes the resistance of thick, non-flowable materials compared to the vertical flights of rectangular blades. The absence of horizontal crossbars also allows the HV Blades to be lifted very cleanly and easily out of a viscous or dense batch.
Ross builds a 250,000-sq.ft. state-of-the-art facility in Wuxi, China to accommodate hundreds of large-scale Dual Planetary Dispersers for the lithium battery industry. Ross Wuxi is the number one supplier of mixing equipment to the Chinese battery industry. To date, it has supplied over 2,000 mixers to this market alone. Dual Planetary Dispersers feature four agitators - two planetary stirrers and two high speed shafts - all rotating on their own axes while orbiting the vessel on a common axis. The robust mixing action is ideal for preparing thick slurries and highly-filled pastes with excellent uniformity and dispersion quality.
Mixing Technology Insights
Mixing Technology Insights offer a brief look into Ross' products, process expertise, and market strengths. The reports delve into how the equipment can be used to improve your process and to add to your bottom line. Below are a few hand picked reports specifically catering to your interests: