Clean water or solids: choosing between the B, K and L series

Ask what the water is carrying before anything else

Solids handling is a physical clearance, not a filter rating. It states the largest spherical particle that can pass through the impeller and casing without jamming. A pump rated at 44 mm will pass a 44 mm stone; it will not screen out a 60 mm one, it will block on it.

That makes it a hard constraint rather than a preference. If the water carries material larger than the rating, no amount of extra flow or head capacity compensates — the pump stops. Conversely, a clean-water pump asked to handle silt and gravel will not merely underperform, it will wear its impeller clearances open and lose head over a season.

So the first question is not how much water, or how high. It is whether there is solid matter in it, and how coarse.

Clean water, high pressure: the K Series

The K Series carries no solids rating at all, which is a design position rather than an omission. Its three models are built for clean water where the requirement is pressure: total heads of 85 m on the K300, 140 m on the K150 and 145 m on the K200.

Flows run from 850 m³/hr on the K150 to 2,300 m³/hr on the K300. That combination — high volume and high head together — is what the range exists for, and it is only available if the water is genuinely clean.

Typical duties are booster and transfer work, clean-water dewatering from a settled source, and any application where the pump sits downstream of screening or settlement.

Solids in suspension, high volume: the B Series

The B Series is the range for dirty water in quantity. Its six models span 245 to 3,350 m³/hr and pass solids from 44 mm on the B100 up to 124 mm on the B400 — coarse enough for construction spoil, pit water and storm debris without a separate strainer stage.

The constraint is head. The B Series operates in a comparatively narrow band, from 42 m on the B400 to 60 m on the B150. If a duty needs more than roughly 60 m of total head, the B Series is out regardless of how well the solids rating fits, and the choice moves to the L Series.

Sewage-impeller options are available where the material is stringy or fibrous rather than granular — sewage, organics and rag will bind a standard solids impeller that would pass a stone of the same nominal size.

Solids and high head together: the L Series

The L Series covers the case the other two ranges cannot: real head with solids still present. Total heads run to 295 m on the L295, and every model retains a solids rating, from 19 mm on the L110 and L125 up to 64 mm on the L250.

The trade is flow. The range spans 112 to 1,258 m³/hr, so it does not reach the volumes the B Series delivers. The L295 produces 988 m³/hr at 295 m of head in a single stage, which matters because reaching that head by staging pumps in series introduces intermediate seals, couplings and service points that a single stage does not have.

The trap: the biggest pump is not the most capable one

Within the B Series, the highest-flow model is not the highest solids-handling model. The B500 delivers 3,350 m³/hr and passes 79 mm. The B400 delivers 2,218 m³/hr and passes 124 mm.

If the water carries coarse material, the B400 is the more capable pump despite moving a third less water. Specifying on flow alone selects the B500 and produces a pump that blocks on material the smaller unit would have passed.

Where the ranges genuinely do not overlap

Some duty points are served by one range and nothing else, and the arithmetic makes that obvious once the tables are read together.

A duty of 2,300 m³/hr at 85 m of total head is met by the K300 and by nothing else in the catalogue — the B Series tops out near 60 m of head, and the L Series tops out at 1,258 m³/hr of flow. That duty is therefore available only if the water is clean. If it is not, the requirement has to change: screen the water upstream, split the duty across multiple pumps, or accept a different operating point.

This is worth establishing early. A duty that only a clean-water pump can meet, on water that is not clean, is a specification problem rather than a purchasing one, and it is cheaper to find before an order than after.

Check total head, not vertical distance

Total head combines the static lift with the pressure lost to friction in the pipework. A duty quoted only as a vertical distance understates the real requirement, sometimes substantially on long runs or small-bore pipe.

This is the most common reason a pump that met its specification on paper fails to deliver on site. Where the discharge run is long, the friction component can exceed the static lift.

Suction lift is not a differentiator across the eBORA range: all models self-prime to 8.5 m, so the pump can sit above the water rather than in it, and no foot valve or vacuum assistance is needed to start or restart. What does change with model size is port diameter — 100 mm on the B100 through to a 500 mm inlet on the B500 — and that has to match the pipework, or the connection throttles the pump.