FLOPAM FO 4498 Equivalent — Medium-Charge Standard-MW Cationic PAM (Bare Grade)

Three facts define the bare row on SNF Catalogue 2007 p.15. First, the charge tier is Medium — the same tier as the SH row directly associated with it. Second, the molecular weight tier is Standard, which is the single published axis on which the two rows differ. Third, the approximate Brookfield readings are 350/200/100 cps at 5/2.5/1 g/L, roughly 54% of the SH figure at 5 g/L. The practical reading is that buying the bare grade buys the charge position without the chain-length step, and the difference is visible in the make-up tank long before it is visible in the filtrate.

That makes the selection question narrower than it first appears. Because the charge tiers are identical, choosing between bare and SH is not a charge decision at all — it is a decision about whether the duty needs molecular weight. Charge-limited duty looks like this: floc forms at a reasonable size but the captured solids release under handling, or supernatant stays hazy while the floc itself looks acceptable. Chain-limited duty looks different: floc forms and then shears apart through a centrifuge bowl or between belt press rollers. The first case points to the bare column as the screening hypothesis, the second to the SH column; either reading is a starting point to confirm on your actual feed, not a conclusion drawn from the visual symptom alone. We publish the SH grade on its own page precisely because the two answers are different.

Our published lane for this row is C8001, which normalises to Medium charge and Medium molecular weight on our own scale. SNF publishes Medium charge and Standard molecular weight on theirs. These are separate vendor scales with no published conversion, so treat the alignment as directional rather than numeric — C8001 is our charge-aligned cationic route, which is the direction this row points. We deliberately do not offer a second screening lane here. C8015 sits in the same band as C8001 on our scale and is an availability option, not a different mechanism; publishing it as an alternative would suggest a second route exists where none does.

The first failure mode is an SH-to-bare substitution made on the number alone. The trigger is a procurement search or a distributor offer matched on "FO 4498" when the incumbent on site is FO 4498 SH — the number is identical and only the suffix differs, so the swap passes a paperwork check. The symptom appears at the equipment: the solution made up at the established concentration is roughly 54% of the previous viscosity at 5 g/L, so the volumetric calibration and dilution-loop assumptions established on the previous solution no longer hold and have to be re-checked by measurement, and floc size or shear survival may change because the source places the two rows in different molecular weight tiers. Raising the dose before confirming the suffix can spend polymer without correcting a grade-class mismatch. The check: confirm the complete label string including the presence or absence of the suffix, then measure the 5 g/L viscosity of the incumbent solution and compare it against the source figures before ordering. A reading near 650 cps means you are running the SH row, whatever the purchase order says.

The second failure mode is carrying over the SH row's make-up and feed settings unchanged. The trigger is a plant that switches to the bare grade and keeps the existing make-up concentration, mixer timing and pump setting because "it is the same grade number". The symptom is a dose that reads correct on the controller and is wrong at the sludge: the viscosity change invalidates the volumetric calibration and mixing assumptions those settings were tuned against, so they have to be re-verified by measurement rather than carried over, and dissolution that appeared complete at the old viscosity is harder to judge visually at the new one. The check is to re-establish three numbers after the change rather than assuming them: weigh actual powder consumption per unit time to confirm the make-up concentration, recalibrate the dosing pump output by measured volume at the intended setting, and re-run a CST or jar test on the new solution to re-establish the active dose. Do this on the first batch, not after a week of drifting results.

Once those two are closed, the remaining procurement decisions for this row are: confirming the exact model string and the absence of a suffix; confirming the duty is charge-limited rather than chain-limited before pricing the Standard MW column; choosing a make-up concentration inside our 1–3 g/L band and re-scaling the feed rate to match; recalibrating the dosing pump after any viscosity change; setting a dissolution and holding time your own fresh-versus-aged testing supports; establishing the active dose by CST or jar test rather than from the datasheet; confirming the document package covers the grade actually quoted; planning a same-material trial before a production commitment; confirming MOQ and packaging format against your storage and handling; and confirming current pricing and lead time with the quotation rather than assuming them from any published table.