How to Select the Right Shaft Seal for Processing

        The protein powder industry is booming. As of 2019, the global protein supplement market was valued at $49.82 billion, according to MarketsandMarkets. Its growth is expected to be 6% per year until 2025. That’s a lot of protein powder. Protein supplement manufacturers need to prepare for growth.
       *People prefer a healthy diet and nutritious foods rich in amino acids, minerals and dietary fiber (found in many types of proteins) *People want to prevent exposure to gluten, lactose and other types of allergens *People are replacing dairy products with meat, eggs and whey protein supports heart health vascular system* People need quality personal care and health products with ingredients that strengthen hair and skin.
        Manufacturing in these industries uses processing equipment such as mixers, stirrers, stirrers, dryers, and kettles to extrude, separate, concentrate, evaporate, and dry the final product. Manufacturers must keep some important considerations in mind during this process:
       * How to make processing as efficient and productive as possible * How to ensure high product safety standards are maintained and maintained
        Why choose rotary shaft seals? Maintaining and improving high levels of production while ensuring product safety requires more than just more powerful and better processing equipment. In fact, one of the keys to success may lie in the hands of a relatively small player who is often overlooked – until he stops working, of course. This unsung member of the team is the seal, specifically the rotary shaft seal or radial shaft seal, which holds the product in place and protects it from contamination.
        Making protein powder is another form of food processing. Moreover, protein contains many amino acids. Therefore, the raw material must pass through a system that separates the target material. To move materials, a variety of conveyors are needed, the design of which includes rotating axles. The shaft must be sealed to prevent product leakage and contamination.
        Various sealing methods have been used over the years: lip seals, mechanical seals and rotary shaft seals. All are designed to prevent leakage and contamination of mixed or transported products. However, there are significant differences in how and how well these seals work.
        Lip seals and mechanical seals use different types of lips to prevent leakage. The rotating shaft creates a hydrodynamic effect that helps maintain the seal, but the operator must also maintain a thin layer of lubricant between the lip and the shaft. The edge makes point contact with the shaft at two angles, and it is this contact with the rotating shaft that causes wear and damage to the shaft. This is the main difference between lip seals and rotating shaft seals.
       Benefits The biggest advantage of lip seals and mechanical packing used in oil seals is their low cost, making replacement relatively cheap (but keep in mind that replacing these seals and wasting product will negate the initial savings).
     The lip seal has a relatively small surface area that can be used to grip a rotating shaft. This design increases the risk of contamination and leakage in all lip seal applications. Ultimately, contaminants can form grooves on the shaft and damage bearings and gearboxes due to particle contamination. *Small lip surface area also results in faster lip seal wear, especially in harsh environments. This requires more frequent replacement of the lip seal, eliminating the initial cost savings. *Metal seals are of limited use because their fixed design causes friction and heat. The viscosity of the sealing fluid directly affects the friction that occurs in the lubricating film. When using low viscosity fluids this can become a serious problem as the lubricating film becomes too thin to maintain seal/shaft separation. * Lip seals do not withstand pressure well, further limiting their usefulness. *Non-rotating lip seals can also cause shaft damage within a short period of time. *Finally, lip seals do not have the government certification required for meat, poultry and dairy processing plants. *Mechanical packing is a packing made of square braided rope, compressed in a gland along the diameter of the shaft. Packing wears out during normal operation of the equipment and requires frequent and costly replacement. *When transporting abrasive bulk material, it migrates into the compaction area and impregnates the rope filler. The abrasive begins to wear along the outer diameter of the shaft. A smaller shaft diameter will reduce the strength and torque of the shaft, and will also make the sealing surface uneven and difficult to seal.
        Advantages of rotating shaft seals. Rotary shaft seals have clear advantages over lip seals and mechanical seals:
        * Rotating design eliminates the risk of shaft damage inherent in lip seals and mechanical packing. * Withstands up to 1/4 inch of shaft misalignment commonly found in bulk material handling equipment without loss of seal. This prevents leaks and loss of material. *Has a larger surface area than lip seals, reducing the likelihood of contamination and leaks. * Its self-lubricating design keeps the seal running dry and reduces wear. *USDA certified for use in meat, poultry and dairy products available. In this hygienic environment, prompt disassembly and cleaning of equipment every day is critical.
        As equipment upgrades and new installations become necessary to keep up with growth, protein powder companies must remember when selecting lip seals and rotary shaft seals that lower price does not equate to return on investment. More frequent repairs and replacement of lip and mechanical seals will quickly eat up the initial savings on the purchase price. When choosing the best solution for your protein processing application, it is important to consider all the costs associated with shaft seal selection.
  GREAT Seal has been providing rotary shaft seal solutions for mixers, screw conveyors and all types of bulk materials handling equipment for over 25 years. For more information, visit gsealing.com.