Non-Galling ILLIUM 8 Alloy Is the Right Recipe for Food Processing Equipment

Food safety and food quality go hand in hand at food processing and equipment manufacturing facilities. To avoid food contact with contaminants including lubricants, metal shavings, and cleaning chemicals, production equipment must adhere to strict regulations from the U.S. Food and Drug Administration (FDA), the U.S. Department of Agriculture (USDA) and 3-A Sanitary Standards, Inc. (3-A SSI).

Food processing equipment manufacturers work hard to balance food safety regulations with equipment that can run at maximum uptime. ILLIUM 8, a nickel-based alloy (equivalent to ASTM A494, grade CY5SnBiM) is corrosion-resistant and designed to operate in contact with stainless steel without galling or seizing. The unique properties of ILLIUM 8 make it key to OEMs achieving this food safety-operational efficiency balance.

Working with ILLIUM Alloys for over 70 Years

Stainless Foundry & Engineering (SF&E) has experience pouring different ILLIUM alloys that goes back decades and is part of the 250 different ferrous and non-ferrous alloys SF&E uses in their castings. The developers of Illium alloy initially formulated it for coal testing equipment because of its sulfuric acid-resistant qualities. SF&E purchased assets of Illium Corporation from Burgess Parr in Freeport, IL in 1956 and have made ILLIUM ever since.

Nickel-based ILLIUM 8 alloy has qualities that are ideal for food, dairy, and pharmaceutical processing equipment. A large percentage of the parts SF&E casts out of ILLIUM 8 are for food and dairy processing OEMs, particularly positive displacement pumps for moving thick foodstuffs like dough, icing, pastes and sauces, and for filling liquids, powders, and granular products into containers. We also have experience casting this alloy for petrochemical usage.

Pump bodies, casings, and covers are typically made of 316L stainless steel for food processing equipment, but the moving parts such as the impellers and rotors are often made of ILLIUM 8.

Remove the Risk of Contamination

OEMs have found that ILLIUM 8 is ideal for food processing machinery where food contact is required, including food pumps, scrapers, bushings, mixing components, meat grinders, dairy products, and pharmaceuticals. Due to its excellent non-galling properties, ILLIUM 8 removes the main risks of equipment-related food contamination: lubricant leaks, metal shavings, and corrosion from abrasive food products or cleaning chemicals.

ILLIUM 8 contains bismuth and tin, which prevents galling and seizing in machinery with metal-to-metal contact. When galling occurs in machinery, metal shavings can enter the food product. Without the risk of galling when parts operate against austenitic stainless steels such as 316L, there is no longer a need for machine lubrication. As an added bonus, ILLIUM 8-machined parts can function well under tolerances as tight as +/- 0.004″ or better on diameters and +/- 0.0015 on axial lengths. This can mean a 99% pump efficiency, where pistons filling machines can deliver food product and empty reservoirs or the tubes leading up to the filler.

Corrosion is another factor that significantly threatens food quality, requiring processing plants to remove it from their machinery constantly. Along with damaging equipment and being difficult to clean, corrosion can provide breeding places for bacteria. ASTM A494, Grade CY5SnBiM is listed in the 3-A SSI as one of the materials which have been shown to be as corrosion resistant as the 300 Series Stainless Steel. ILLIUM 8 conforms to the requirements of ASTM A494 for grade CY5SnBiM.

Sand Cast ILLIUM 8 Rotor (left) and Positive Displacement Pump (right)

Experts at Pouring ILLIUM 8

So why doesn’t every OEM in the food and beverage industry use ILLIUM 8? For many foundries, ILLIUM 8 is difficult to pour without defects. SF&E has poured ILLIUM for food applications over the past 65+ years and has developed techniques and processes to produce high-quality castings that meet OEM specifications efficiently.

First, ILLIUM 8 can be easily machined with or without any cooling fluid with carbide inserts. It does not have to be welded or heat treated, so castings are supplied as-cast or in a semi-machined condition. Second, non- metallic inclusions are limited by constant monitoring of melt and pour procedures. An inexperienced foundry may struggle with these aspects and have excessive scrap.

“SF&E has established standard processes backed up by highly experienced production and metallurgy teams,” says Vijay Talwar, Director of Metallurgy & Process Engineering at Stainless Foundry & Engineering. “With our experience and our expertise, we are always looking for new applications that ILLIUM 8 can be ideal for, new OEMs in the food/beverage and petrochemical industries we can support, and new ways to continuously improve.”

To learn more about how SF&E can provide your company with high-quality food-grade castings, please get in touch with us today. Contact Us