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End Suction Pump
QI(H) Series · ISO 2858 Pattern · 120+ ModelsBBP QI(H) Centrifugal Pumps for Water Supply, HVAC & Industrial Duty
End suction pumps designed to the ISO 2858 dimensional grid covering flow ranges from 3.6 to 1,500 m³/h and head ranges from 5 to 147 m in over 120 model arrangements. Each unit leaves our Beijing foundry in one vertically integrated process—cast, machined, assembled, and hydrostatically tested per ISO 9906.
Flow Range
3.6 – 1,500 m³/h
ISO 2858 / EN 733
Head Range
5 – 147 m
Peak Efficiency Up to 86%
Motor Power
0.37 – 315 kW
ISO 9906 Hydrostatic Tested
Impeller Materials
Cast Iron · Bronze · 316 SS
Industrial Duty Construction
Buyer focus: Engineer · Procurement · Plant Manager
Underperforming HVAC Loops, Water Supply Shortfalls & Industrial Transfer Headaches — The Three Pump-Selection Pain Points You Need to Solve
An end suction pump is a single-stage, concentric, centrifugal pump with one axial inflow and a 90° radial outflow—a workhorse of water transfer found in the water industry ever since ISO 2858 established its dimensional pattern in 1975. These pumps deliver head and flow combinations better suited to HVAC, municipal, and light industrial treatment than any other enclosure within this size class. The outline is simple; choosing the right pump is complicated. Nearly every pump we have examined failed because the wrong duty point was coupled with the wrong pump.
HVAC Loop Efficiency Losses
An inadequately selected chilled-water circulator running on average 1800 hours per year 15% away from best efficiency point consumes measurable more energy and reduces bearing lifetime. Selecting the correct impeller trim set at a fixed speed confines that penalty where it belongs, in the past.
Water Supply Pressure Gaps
Municipal boosting stations, building pressure systems all require steady head at varying flow, while an oversize end suction pump results in cycling of power and an under size one prevents achievement of design pressure on peak flow.
Industrial Transfer Mismatches
Different process transfers in clean water, cooling-tower make-up, fire-protection, and irrigation applications have different NPSH headroom, materials of construction, and running profiles. A simple catalog pump that ‘fits the flow’ seldom matches all four.
How the BBP QI(H) Series Solves Each Pain
The QI(H) line stands because end suction duty isn’t one problem; it is three solution groups in a single linear envelope. We communicate with more than 120 model variants all possessing ISO 2858 interchangeability but selecting bronze, cast iron, or 316 stainless steel for the liquid in your system.
Drop-in compatibility
Every QI(H) frame sits on the same flange centerline as Grundfos NB, Sulzer SES, and Xylem Lowara NSC pumps of the same duty point. That means your piping, baseplate, and coupling guard stay where they are when BBP replaces an existing ISO 2858 / EN 733 installation.
Vertically Integrated Manufacturing
The production of every single pump is hydrostatically tested to ISO 9906 with a mechanical seal or gland pack in the same stuffing box. All of our salt sand cast the volute, all of our line machines the shaft sleeve, all of our test logs the Q-H curve before sending it east. What you receive is precisely the same typewriter as you specified, not a standard drop ship.
Buyer focus: Engineer (primary) · Procurement (RFQ match)
BBP QI(H) Series — 120-plus Model Variants for Every Duty Point
The prefix QI(H) describes the standard head range of our end-suction pumps; the suffix “High head” describes the extended high-head operational range. Model numbering within each family system remains a standard ISO 2858: suction and discharge sizes, nominal impeller. A, B, C, or S suffix indicate the impeller trim.
Three Representative Model Classes
QI 50-32-125
Flow 12.5 m³/h · Head 20 m · 2.2 kW
Economical role within a building-pressure boosting, space-heating circulation, workshop cooling loop. Cast iron or bronze construction.
2900 rpm · 50 Hz
DN50 suction / DN32 discharge
NPSHr: 2.0 m
DN50 suction / DN32 discharge
NPSHr: 2.0 m
QI 125-100-315
Flow 160 m³/h · Head 32 m · 22 kW
Business pump distribution for commercial HVAC chilled water, municipal booster stations, or light industrial process cooling. 316 stainless steel/advanced stainless impeller optional.
1450 rpm · IE3 motor
DN125 suction / DN100 discharge
NPSHr: 3.5 m
DN125 suction / DN100 discharge
NPSHr: 3.5 m
QI 250-200-500A
Flow 1,080 m³/h · Head 62 m · 280 kW
Municipal district cooling plants, lobby booster stations, design high heads for domain grade applications. A head efficiency of eighty-six percent within the this envelope air on the money.
1450 rpm · heavy-duty bearings
DN250 suction / DN200 discharge
NPSHr: 6.5 m
DN250 suction / DN200 discharge
NPSHr: 6.5 m
Performance Matrix — Representative 20-Model Selection
| Model | Flow (m³/h) | Head (m) | Speed (rpm) | Power (kW) | Efficiency (%) |
|---|---|---|---|---|---|
| QI 40-25-125 | 6.3 | 20 | 2900 | 0.75 | 48 |
| QI 50-32-125 | 12.5 | 20 | 2900 | 2.2 | 55 |
| QI 50-32-200 | 12.5 | 50 | 2900 | 4.0 | 52 |
| QI 65-50-125 | 25 | 20 | 2900 | 3.0 | 62 |
| QI 65-40-200 | 25 | 50 | 2900 | 7.5 | 58 |
| QI 80-65-125 | 50 | 20 | 2900 | 5.5 | 69 |
| QI 80-50-200 | 50 | 50 | 2900 | 15 | 66 |
| QI 100-80-125 | 100 | 20 | 2900 | 11 | 74 |
| QI 100-65-200 | 100 | 50 | 2900 | 22 | 72 |
| QI 125-100-200 | 200 | 20 | 1450 | 15 | 78 |
| QI 125-100-315 | 160 | 32 | 1450 | 22 | 78 |
| QI 150-125-250 | 315 | 20 | 1450 | 30 | 80 |
| QI 150-125-400 | 250 | 50 | 1450 | 55 | 79 |
| QI 200-150-250 | 500 | 20 | 1450 | 45 | 82 |
| QI 200-150-400 | 400 | 50 | 1450 | 90 | 82 |
| QIH 125-100-400 | 160 | 80 | 2900 | 55 | 75 |
| QIH 150-125-500 | 250 | 100 | 2900 | 110 | 78 |
| QIH 200-150-500 | 400 | 125 | 2900 | 200 | 80 |
| QI 250-200-400 | 800 | 50 | 1450 | 160 | 84 |
| QI 250-200-500A | 1,080 | 62 | 1450 | 280 | 86 |
source: QI(H) 2024-2025 water duty points duty 20 C / SG 1.0 factory brochure. Complete 120-model specification tables available on request.
Reading a QI(H) Model Code: QI(H) 125-100-315A
QI or QIH
Series identifier. QI is for standard head range; QIH has high-head duty, with a reinforced casing and larger-diameter impeller.
125
Suction nominal diameter in millimeters (DN125). The pipe flange on the axial inlet.
100
Discharge nominal diameter (DN100). The 90-degree radial outlet where the fluid exits.
315
Nominal impeller diameter in millimeters. It sets the head at a given speed from the 120-models–the bigger the impeller, the higher the head.
A·B·C·S
Impeller trim within a single frame. “A” is full diameter; “S” is a trimmed version for the extra-lower head duty on the same casing.
Materials & Seal Options
| Component | Cast Iron (GG25) | Bronze (G-CuSn10) | 316 Stainless Steel |
|---|---|---|---|
| Casing | Standard clean water | Seawater / salt spray | Potable / chemical |
| Impeller | Cast iron or bronze | Bronze | 316 SS investment cast |
| Shaft sleeve | 420 SS standard | 316 SS | 316 SS or Hastelloy |
| Wear rings | Replaceable cast iron | Replaceable bronze | Replaceable 316 SS |
| Seal | Mechanical (Burgmann-compatible) or gland packing | Mechanical or packing | Mechanical (EPDM / Viton) |
Note: Your maintenance team can switch from mechanical seal to gland packing and vice versa without re-machining or re-shimming. This single feature increases a frame’s life from one phase to the next.
Need the full specification of a specific model?
Download the QI(H) catalog
Buyer focus: Engineer (technical validation)
Back Pull-Out Construction, Replaceable Wear Rings & Interchangeable Seals — How the QI(H) Frame Earns Its Service Life
The longer a pump goes without a strip-down, the more economical it becomes. The QI(H) frame introduces three design innovations that minimize mean time to repair and that push back on the interval between overhaul.
Back Pull-Out Maintenance
The entire rotating assembly, impeller, shaft, wear rings, mechanical seal – can be removed from the volute casing without disturbing the piping. Technician turns off the coupling, slides out four casing bolts, and the power end with its support feet rolls out. Piping, alignment, and seal are untouched and the entire job takes four hours instead of three days.
Replaceable Wear Rings
The impeller and volute casing both have replaceable wear rings. Head, little-by-little, goes away as the service hours accumulate. The field maintenance report indicates when head drops below the point where the pump slope diverges from the predicted one and your maintenance crew pulls the two wear rings and restores it to Rated Efficiency band in one short workshop session. The other alternative is a major overhaul with either a full impeller or casing replacement.
Interchangeable Seal Chamber
The stuffing box housing accepts either a single mechanical seal (John Crane Type 21; Burgmann MG1; equivalent) or a ‘typical’ gland packing assembly. Same housing, different cartridge. With one frame style, your process engineer can specify packing for a so-called forgiving clean-water application, or a mechanical seal for a rated-potable water line.
“The single next-generation feature that gets a plant maintenance team to purchase a pump platform for a large number of installations; the replaceable wear rings and the interchangeable seal chamber: no one wants to carry two spare-parts inventories. QI(H) lets the user stock one.”
Shaft & Bearing Arrangement
- Shaft deflection at seal face: under 0.05 millimeters at rated duty–the limit where mechanical seal viability stays assured.
- Bearing life (L10): designed for 40,000 hours at rated duty within the Hydraulic Institute’s preferred operating region.
- Coupling configurations: close-coupled for minimum floor space, or frame-mounted with flexible coupling for off-line service capable bearings.
- Motor sizing covers: 0.5 hp up to 420 hp (0.37 – 315 kW) depending on duty point, with IE3 efficiency as the default motor class.
Buyer focus: Engineer + Plant Manager + Procurement
End Suction vs Horizontal Split Case vs Vertical Multistage — Numeric Comparison at the Same Duty Point
Various pump designs battle for the same 200 m³/h / 50 m duty point, but are optimized for differing cost profiles, footprints, and ease of maintenance. Conscientious designers compare like-for-like flow rates without understanding NPSH, footprint, or operation cost. The optimal choice is contingent on the fluid, the run-hour profile, and specific plant industry needs.
| Dimension | End Suction (BBP QI 125-100-315) | Horizontal Split Case | Vertical Multistage |
|---|---|---|---|
| Flow range (m³/h) | 200 | 200 | 200 |
| Head range (m) | 50 | 50 | 50 (via 3-stage) |
| Typical footprint (m²) | 1.2 | 2.4 | 0.6 |
| NPSHr (m) | 3.5 | 2.2 | 4.8 |
| Peak efficiency (%) | 78 | 82 | 72 |
| Relative capex (index) | 1.0 | 1.7 | 1.4 |
| Maintenance skill | Technician | Millwright | Specialist |
| Typical application fit | HVAC · water supply · general transfer | High flow / low NPSH plants | Space-constrained boosting |
Capex index: based on End suction baseline = 1.0. true cost varies with material, motor class, and order volume – contact us for a quote for your application.
Decision Tree — When End Suction Wins
1
Flow ≤ 2,000 m³/h AND head ≤ 150 m:
End suction pump is the cost-effective, efficient solution. The QI(H) pump series starts here.
2
Flow > 2,000 m³/h OR NPSH margin is limited:
Horizontal split case pump incurs its footprint and cost penalty. End suction means oversized frames at this duty.
3
Footprint < 1 m² AND flow is moderate:
Vertical multistage pump solves boosting at this space-constrained duty. Maintenance ease is the decision factor.
4
Mixed-use building duty:
Incorporating chilled water, domestic water, and fire protection systems: combine end suction on dual loops with vertical multistage on the third boost loop to minimize platform costs.
Brand Anchor — Where BBP QI(H) Sits Among Pattern-Compatible Alternatives
BBP pumps are designed to fit the ISO 2858 flange pattern, meaning the QI(H) type product replaces competitor offerings on the same footprint without pipework changes. Use these benchmarks to match a QI(H) to an existing installation:
| Alternative Platform | Standard | Typical Duty Window | BBP QI(H) Equivalent |
|---|---|---|---|
| Grundfos NB / NBG series | EN 733 / ISO 2858 | Up to 2,850 US gpm / 561 ft | QI 200-150 / QIH 200-150 |
| Xylem Lowara e-NSC | EN 733 | Up to 240 m³/h / 60 m | QI 100-65 / QI 125-100 |
| Pentair Aurora 3800 | ANSI B73.1 pattern | HVAC / municipal | QI 80-65 / QI 100-80 (check flange drilling) |
| Sulzer SES / SKS | EN 733 | Drinking water certified duty | QI with 316 SS option |
Buyer focus: Plant Manager + Engineer
Proven in HVAC, Municipal Water Supply, Fire Protection, Irrigation & Cooling Tower Service
A ISO 2858 pattern pump offers a universal clean-water appliqué, but market specifics guide each selection. The QI(H) range supplies these different needs through appropriately matched material, motor class, and seal design.
Commercial HVAC
Offices, hotels & data centers with chilled-water, condenser-water, and hot water sys adds.
Typical selections: QI 100 / 125 / 150 frames
Municipal Water Supply
District booster stations, elevated tank fill, and transfer plant come next.
Typical selections: QI 150 / 200 / 250 frames
Fire Protection
Trunk fire pump & sprinkler distribution systems, often with UL listed driver.
Typical selections: QIH high-head series in 316 SS
Irrigation
Center-pivot feed, drip-line irrigation, and greenhouse air handling.
Typical selections: QI 65 / 80 / 100 in iron or bronze
Cooling Tower Circulation
Process cooling condenser-water loops.
Typical selections: QI 100 / 125 with bronze fittings
Industrial Transfer
Light-duty process water, flushing water, and boiler feed systems for light manufacturing, beverage, & light chemical facilities.
Typical selections: QI 80 / 100 with 316 SS
Potable & Seawater Service
Potable water service needs the 316 SS version with NSF/ANSI 61 wetted parts — specify at RFQ time because this also upgrades the seal elastomer. Brackish or seawater service needs bronze case plus duplex SS shaft and hardware.
Abrasive & Solids Handling
For heavier-solids or abrasive service, explore our horizontal slurry pumps for mining and mineral processing, or our self-priming sewage pumps for wastewater handling.
Buyer focus: Procurement + Engineer
ISO 2858 Pattern Dimensions, ISO 9001 & 14001 Certified Manufacturing, Third-Party Inspection Ready
Standards and certifications address two different questions. A dimensional standard like ISO 2858 verifies that your pump falls within an existing footprint—no piping changes needed. A quality management standard like ISO 9001 verifies that the factory that built the pump controls a documented process from casting to shipped crate.
ISO 2858
End-suction centrifugal pump dimensional pattern (16 bar rating)
ISO 9001
Quality management system — BBP Beijing
ISO 14001
Environmental management system
OHSAS 18001
Occupational health & safety management
CE Marked
European Machinery Directive conformity
ISO 9906
Hydrostatic performance test per pump unit
ISO 2858 Pattern — What It Guarantees
ISO 2858:1975 outlines the critical design and interface parameters of end-suction centrifugal pumps rated for 16 bar maximum working pressure. It determines the flange size, shaft size and casing envelope in such a way that pumps from various manufacturer are interchangeable or replaceable with a few modifications. EN 733 and DIN 24255 possess one of such dimensional Family.
That equates to a QI(H) pump retrofitting a Grundfos NBG, a Sulzer SES or a Xylem Lowara NSC on the same duty point – without modification to base frame, pipes or coupling. We arrive with the flange drillings already matched to your installation – you tell us PN 10 or PN 16 at RFQ time.
Third-Party Inspection — Available on Request
Any QI(H) pump is hydrostatic tested for the casing as per the ISO 9906 before it is dispatched from our factory.
On demand the products can be checked by SGS, Bureau Veritas or TV at the buyer’s cost – witnessed function test, material certificate assessment and dimensional study compared to purchase order.
Goods are released by our QA team only after the inspector signs off.
Buyer focus: Procurement (primary) + Plant Manager (budget)
End Suction Pump Procurement Guide — Pricing Factors, Lead Times, OEM Support & Export Experience
Five questions are asked by the Buyers prior to a purchase order; what is the pricing based on, what speed is the delivery, what is the MOQ, what is the warranty really covering, and how do you do OEM branding. How does BBP currently handle these?
Pricing Factors Framework
Pump Frame Size & Power Class
The DN rating and motor kW dominate the unit cost. Small-frame clean-water pumps are a different price tier from large-frame high-head duty pumps.
Material of Construction
Cast iron is the baseline. Bronze casing adds a material premium. 316 stainless steel investment-cast wetted parts add a second premium.
Motor Efficiency Class
IE2 is the entry baseline. IE3 premium-efficiency and IE4 super-premium carry progressive motor cost premiums. Most EU and North American buyers now specify IE3 by default.
Seal Configuration
Gland packing is the economical choice for clean water with predictable leakage tolerance. Single mechanical seal is standard. Double mechanical seal with flush plan is specified for hazardous or hot duty.
Order Quantity
MOQ is one pump for stock models; volume discounts apply on orders of 10 or more of the same model and configuration.
Certification & Inspection Scope
Standard factory test is included. Witnessed third-party inspection (SGS / BV / TÜV) is at buyer’s cost and adds 5 to 10 working days to the schedule.
Contact BBP for a clearly set out quote applicable to your duty point, material and scope of certification.
Lead Time Timeline
7 days
Stock models
Standard QI range, cast-iron casing, consignment ex – works Beijing within 7 working days.
30 – 45 days
Made to order
Non-stock material/motors combination, full cycle of manufacturing and testing
45 – 60 days
OEM custom
Private-label branding, custom nameplate, custom paint, documentation set.
3 – 5 days
Urgent air freight
Suitable for critical-path projects with a per-kg freight surcharge quoted at RFQ.
OEM Customization — Four Steps from Spec to Crate
01
Specification Lock
Duty point, material, motor, seal, certification, all in one signed datasheet all locked in.
02
Tooling & Pattern
We cast pattern in our foundry for new sizes, regular sizes go directly to the standard.
03
Sample Build & Test
First article is constructed, hydrostatically pressure tested and sent to buyer for approval prior to bulk.
04
Bulk Production & Shipment
Approved sample is used for bulk casting, machining, assembly, test, packing & dispatch.
Warranty Scope
-
Warranty period runs 12 months from the bill-of-lading date, or 2,000 operating hours, whichever comes first.
-
Covered failures include casting defects, machining tolerances outside ISO 2858 spec, motor failures traceable to manufacturing, and seal or bearing failures attributable to assembly.
-
Excluded items are consumables such as gland packing, cavitation damage from under-specified NPSH margin, abrasive wear from solids in the pumped fluid, and storage or installation damage.
-
To file a claim, email the serial number and failure photos to our after-sales desk; we respond within two working days and arrange replacement parts or return-to-factory at our cost if the claim is valid.
Export Experience & Incoterms
BBP ships to buyers across the European Union, the Middle East & North Africa, Southeast Asia, and Latin America — our standard Incoterms are FOB Tianjin, CIF destination port, or DDP where the buyer wants a landed-cost quote.
Payment terms are 30 percent T/T deposit with 70 percent against shipping documents, or an irrevocable L/C at sight for orders above a threshold our sales desk will confirm.
Digital Engineering Solutions
Engineering & Selection Tools
Access our suite of precision digital tools designed for plant engineers and procurement teams. Validate duty points, calculate total cost of ownership, or find direct ISO 2858 replacements instantly.
Duty Point Selector
Input your specific flow (m³/h) and head (m) requirements to instantly generate pump curves, NPSHr data, and optimal motor sizing for the QI(H) series.
Launch SelectorISO 2858 Replacement Finder
Enter your existing pump’s nameplate data (e.g., Grundfos, Xylem, Pentair) to instantly find the 100% dimensionally compatible BBP drop-in equivalent.
Find ReplacementTCO Framework Calculator
Compare the 10-year Total Cost of Ownership between baseline IE2 and premium IE3/IE4 configurations based on your local power costs and operation hours.
Calculate TCO
Knowledge Base
End Suction Pump FAQ — Engineering, Selection, Standards & Purchase
End suction pump has single entry impeller, axial suction on one end of casing and radial discharge at 90-degree angle. Horizontal split case pump has double entry impeller, with axial suction and discharge on opposite sides of a casing split horizontally and requires lower NPSH at same flow. For flows up to approx 2,000 m³/h end suction wins on footprint and capex, split case wins on efficiency and NPSH.
Yes — specify the 316 stainless steel variant with NSF/ANSI 61 compliant wetted parts at RFQ time. Seal elastomer selection also needs to match drinking-water service, typically EPDM. We will confirm the specific model and material combination on the quote.
ISO 2858:1975 defines the dimensional envelope, flange sizes, shaft extension, casing footprint, for end-suction centrifugal pumps rated to 16 barg. A QI(H) pump will be cross-compatible with any other pump of the same construction standard and require no piping changes, as the equivalent of an EN 733 or DIN 24255-compliant E1 medium-duty N, NB, or SEC pump in Europe, or an Xylem Lowara NSC on a defined duty point, for the end user in the EU.
Provide flow in m³/h or US gpm, head in meters or feet, fluid and temperature, and the power supply frequency. We plot the duty point on the QIH selection curves, and send back three candidate models—generally one that fits on the head side, one that fits on the flow side, and the best efficiency point match. You choose according to the NPSH margin and footprint.
Mechanical seal has become the norm for sealed-system duty, for potable water, and whatever service where the odd drop of leakage is not tolerable. Gland packing is the economical solution for clean water, with a drip-tray under the pump, where a small intentionally controlled leak cools the packing, and the maintenance men re-pack twice a year. QI(H) accepts either in the same stuffing box.
Stock models dispatched within 7 working days ex-works Beijing. Made-to-order profiles (non-stock items and motor classes) 30–45 days. OEM private label builds 45–60 days with sample approval. Airfreight available for expeditious projects at a per-kilogram supplement.
Yes – The QI(H) pumps are supplied to the same dimensional family as EN 733 / DIN 24255, which means compatible flange-to-flange and footprint-to-footprint with European applications. As long as you specify flange drilling PN 10 or PN 16 at the RFQ stage we will match your existing site.
Yes. All OEM standard options such as custom nameplate engraving, custom paint color to buyer’s RAL code, as well as custom documentation pack are available. Private-label builds use the four-step OEM flow above add 45 to 60 days to the total lead-time depending on the detail of specification lock.
All standard build ships with IE3 premium-efficiency IEC motors 380V / 50Hz three-phase. We can also provide 400V / 50Hz, 460V / 60Hz, and 220V / 60Hz build for export markets. Motor enclosure is TEFC or ODP depending on buyer specification. IE4 super-premium motors are available at premium cost.
Initial capex on our standard build is generally 20 to 40 percent less than an equivalent Grundfos NB or Xylem Lowara NSC pump, subject to material and motor class. Total cost of ownership is dependent on your energy cost, run-hour profile and maintenance rate – we will guide you through a framework during the RFQ process. Buyers specifying IE3 motors, replaceable wear rings, and our 12 month warranty find the TCO gap to be in single digits over 5 years.
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