A twin-screw pump is a twin-screw pump — two rotors, timing gears, no metal contact — until you look at what the media demands of the wetted path. The industrial build and the hygienic build differ not in principle but in every surface the product touches, and the gap decides whether your pump passes audit or feeds the scrap bin.
The industrial build
Industrial twin-screw pumps move fuel oil, crude, bitumen and wastewater. Cast housings, mechanical seals chosen per media, rotors optimized for viscosity and solids tolerance. The ALLWEILER 216.10 class is the archetype: 535 m³/h of fuel oil through a pump designed for decades of continuous marine or plant duty. Cleanliness means keeping grit out of the bearings; nothing more.
The hygienic build
Hygienic twin-screws — the Fristam FDS, Q-Pumps QTS, Waukesha 015-UTS class — serve yogurt, cream, pharmaceutical syrups. Every wetted surface is 316L or better, electropolished; seals are FDA/3A-listed elastomers; the casing drains fully with no dead legs; CIP (clean-in-place) is a design requirement, not an afterthought. Surface roughness is measured and certified, because bacteria measure it too.
The decision rule
Follow the auditor, not the fluid. If a regulation (3-A, EHEDG, FDA, pharma GMP) governs your product contact, you need the hygienic build with its certificates — no industrial pump is "clean enough." If no regulation governs contact, the hygienic premium buys nothing but polish. In both worlds, the flow measurement downstream should hold the same hygiene or industrial class as the pump.
Can a hygienic pump run my fuel-oil transfer?
Mechanically yes, economically no — you pay hygienic prices for elastomers and polish that industrial media will chew. And its certificates are worthless in your duty.
Do industrial builds handle CIP?
They handle flush-out, not validated CIP. If your recipe changes daily and the cleaner runs through the pump, the hygienic build's full-drain geometry is what keeps yesterday's product out of today's batch.
