ULTRA-SANITARY STAINLESS STEEL (USSS):
Used primarily when sanitary construction is specified for food, chemical and pharmaceutical industries requiring stainless steel product contact, a finish with no cracks or crevices, and a high degree of interior polish. Interior is polished to 120 grit final finish.
- Construction Materials
- Stainless steel product contact surfaces (surfaces in direct contact with the material being processed or handled and/or exposed to material dust or residue).
- Stainless steel externals except as noted or as determined and defined by the customer. Use only stainless or plated fasteners; no unfinished carbon steel (black) fasteners.
- Product contact zone – Continuous TIG welds free of overlaps, cracks and surface pores.
- Exterior – Continuous TIG welds free of overlaps, cracks and surface pores.
- Welds in the Product Contact Zone – Grind and polish welds smooth to 120 grit final finish.
- Exterior Welds – Remove slag and weld “spatter”.
- Surfaces in the Product Contact Zone – Grind all surface imperfections and manufacturing “scars” smooth and power tool polish to 120 grit final finish with a uniform “grained” appearance.
- Exterior Surfaces – Exterior to be “sugar” blasted to a uniform finish.
- Interior and exterior to be thoroughly cleaned prior to shipping to remove soil, fabrication debris and hand prints.
- Exterior fabricated mild steel to be cleaned, masked and painted with Steel-It stainless topcoat over rust inhibitive primer.
- Purchased components (bearings, reducers, motors, etc.) to be painted with Steel-It stainless topcoat over factory applied coatings.
- Exposed mild steel shafts and unfinished mild steel components on motors, reducers, etc. shall be protected with FDA compliant rust-inhibitive coating (grease).
- End Plate Design – U-Shaped end plate with legs and gusseted C-Shaped horizontal bearing brackets. Bearing to be mounted in suspension on brackets.
- End Plate Attachment – Drive end plate to be bolted and interior seam sealed with small, continuous fusion weld at final assembly. Weld discoloration to be removed. Tail end plate to be welded.
- Mixer Support – Square tubing legs mounted on the end plates. Locate so as not to interfere with discharge gate or take-away conveyor system. Discharge height to be specified.
- Ribbon Shaft Assemblies – Cross arm collars to be eliminated. Cross arms to be continuously welded to the main shaft. Ribbon “wraps” or backing straps shall not be used. Ribbons to be continuously welded to the cross arms. Proper ribbon to tub wall clearance to be determined at assembly and the seal mounting plates welded-in-place to the end plates (non-adjustable).
- Paddle Shaft Assemblies – Keyed and bolted cross arms shall be replaced with welded-in-place cross arms. Paddles to be continuously welded to the cross arms. Proper paddle to tub wall clearance to be determined at assembly and the seal mounting plates welded-in-place to the end plates (non-adjustable).
- Drop bottom mixers do not meet the strict requirements for sanitary applications.