New Sealing System for Hot-Oil Applications

To eliminate vegetable oil and steam leaks in the production of snack foods, Neocooper Industrial Solutions has developed together with the seal manufacturer CinchSeal a brand new mechanical sealing system for drive shafts of frying processors, making the production of fried foods safer, more hygienic and more ecological as well as economical. The result of a three-year test and improvement period, the new CinchSeal NECAS seal is the solution for all “Hot Oil” applications in the food and process industry.

The core of the seal is a split elastomer made from AFLAS®, a new synthetic rubber that has all the benefits of Viton® but is also resistant to hot organic steams and vapours. The split AFLAS® elastomer is placed around the drive shaft and is glued together at the dovetail joint. It is secured with a hose clamp and rotates together with the drive shaft, protects the shaft against wear and prevents leakage along the shaft. The elastomer transfers the rotational movement onto two PTFE sealing discs, the Rotor Cups, which also rotate with the shaft. The PTFE Rotor Cups on the product and atmospheric side seal off against a stainless steel housing which creates an internal compression, thereby forming an internal and external sealing surface. The PTFE Rotor Cups and the housing are also split, so that no disassembly of the bearing and motor is required during installation.

This project has been started at an international snack foods manufacturer with an iconic crisps brand who was looking to replace the old packing seals, because the constant leakage burned the frying oil in the cord gaskets, causing smoke, odor and harmful substances such as trans fats and carbons. In addition, the cord gaskets caused wear and damaged the drive shafts, so they had to be metal sprayed after ten years in operation. This had been a time-consuming and expensive maintenance job for 13 shafts with a length of 2.5 meters and a diameter of 200 millimeters per processor line. The constant leakage also led to intensive cleaning and frequent bearing damage.

After an initial test phase of eight weeks with mechanical seals from different manufacturers, CinchSeal’s sealing system was the only solution that showed no leakage and the customer decided to cooperate with Neocooper Industrial Solutions to develop a seal model that would meet the specific requirements and a service life of at least 24 months. The seals could not be provided with a compressed air connection, usually necessary to support the compression in the seal housing, so a model with hose clamp was designed. The connection of the split PTFE Rotor Cups had to be reinforced in order to achieve the required service life with an operational process time of 4 times 6 months continuously, with one week for maintenance and cleaning in between. In addition, the standard silicone elastomer was found not to be sufficiently resistant to the hot organic steam and had to be replaced after 18 months. Therefore, after an intensive study of different rubber materials, a test with the new AFLAS elastomer was conducted and this was the breakthrough to meet all the customer's requirements.

The customer has since taken the decision to equip all six processor lines with the new CinchSeal NECAS seal and has mad this seal his Global Standard for all future production lines. The first processors have been retrofitted in 2021 and will continue to be upgraded during the next years.

For more information about our products and services feel free to contact Christian Wermeter of Neocooper Industrial Solutions or send us a message !