4 Inch Submersible Pump
If your site needs a pump that can sit right in the water and keep moving large volumes of liquid without a dry-mounted suction system to babysit, the Hydroman® 100TJQ22-50H6A is built for exactly that job. It's a 22 kW electric submersible centrifugal pump with a 100 mm (4 inch) discharge, designed to be lowered straight into a sump, pit, tank, or open water source and left to run.
Below you'll find the full technical picture, how the pump actually works, where it fits best, and how it compares to a conventional surface-mounted centrifugal pump — so you can decide with confidence whether it's the right fit for your project, not just take our word for it.
How a Submersible Centrifugal Pump Actually Works
There's nothing exotic about the principle — it's the same centrifugal mechanism you'd find in a surface pump, just packaged to run underwater.
Liquid enters through the suction inlet at the base of the pump, which sits below the waterline. The motor spins the impeller at speed, and as the liquid passes through the impeller vanes it picks up velocity. That velocity is converted into pressure as the liquid moves outward into the volute casing, and from there it's pushed out through the 100 mm discharge outlet toward your pipeline. Because the whole unit is submerged, there's no long suction line to prime and no risk of the pump losing suction — the liquid is already right there at the inlet.
This is really the answer to a question a lot of buyers ask us directly: is a submersible pump a centrifugal pump, or something different? The two words describe two separate things. "Submersible" tells you how the pump is installed — underwater, close-coupled to a wet-end motor. "Centrifugal" tells you how it moves liquid — by spinning an impeller. A pump can be, and very often is, both at once. The 100TJQ22-50H6A is a good example: submersible in configuration, centrifugal in operating principle.
22 kW of continuous-duty power. The motor is sized for sustained industrial operation, not intermittent light-duty pumping — it's built to run shifts, not minutes.
A 4-inch discharge that matches real jobsite flow. A 100 mm outlet gives you enough capacity for genuine dewatering and transfer work, without oversizing the pipeline or fittings you already have on site.
Submerged installation cuts out a lot of the complications. No suction piping to lay out, no foot valve to maintain, no priming step before startup. You lower it, connect the discharge hose or pipe, and switch it on.
Single stage, single suction hydraulic design. This keeps the internal flow path simple, which means fewer wear points and more straightforward maintenance compared with multistage designs — a real advantage when the pump is doing continuous dewatering or transfer duty rather than high-head boosting.
Class H insulation and IP68 protection. The motor is designed to handle the heat and moisture stress of running fully submerged for extended periods, which is the actual failure point on cheaper submersible motors.
Key Technical Data
| Parameter | Specification |
| Model | 100TJQ22-50H6A |
| Pump Type | Vertical submersible centrifugal pump |
| Brand | Hydroman® |
| Discharge Diameter | 100 mm / 4 inch |
| Motor Power | 22 kW |
| Drive Type | Electric, three-phase |
| Poles / Speed | 6-pole, ~980 rpm (50 Hz) |
| Installation | Vertical, fully or partially submerged |
| Hydraulic Design | Single stage, single suction centrifugal |
| Insulation Class | H (180°C) |
| Protection Rating | IP68 |
| Cable | Submersible-rated rubber/polyurethane cable, standard 10 m (custom lengths available) |
| Max. Particle Size | Depends on impeller variant — clean water, or semi-open/vortex impeller for solids-laden liquid |
A quick note on how to read this table: flow and head figures for any 22 kW / 100 mm submersible unit will vary depending on the impeller trim and the operating point you run it at, so we always confirm the exact performance curve against your actual head and flow requirement before you order, rather than quoting one number that may not apply to your system.
This is probably the comparison we get asked about most, so let's put it plainly.
| Feature | Submersible Centrifugal Pump | Surface-Mounted Centrifugal Pump |
| Installation | Underwater / submerged in the sump or tank | Above the liquid, on a dry foundation |
| Suction piping | Minimal to none | Required, and needs to be sized and sealed correctly |
| Priming | Not required — inlet is already flooded | Often required before each startup |
| Footprint above ground | Very small | Requires pump house or platform space |
| Noise and vibration at surface | Low (motor is underwater) | Higher, since motor and casing sit in the open |
| Typical use case | Pits, sumps, tanks, dewatering, drainage | Fixed water transfer systems, booster stations |
| Access for maintenance | Requires lifting the unit out | On-site access without lifting |
On the difference between "submersible pump" and "centrifugal pump" specifically — this trips a lot of people up because the terms get used loosely in casual conversation. "Submersible" is an installation classification. "Centrifugal" is a hydraulic classification, describing how the impeller moves liquid, as opposed to positive-displacement designs like diaphragm or piston pumps. So when someone asks about the submersible pump and centrifugal pump difference, the honest answer is: they're not two competing categories, they're two axes you can combine. A submersible unit is very often centrifugal on the inside, including this one.
On efficiency — we won't tell you a submersible pump vs. centrifugal pump efficiency comparison has a clean winner, because it doesn't. Whether a submersible or a surface pump comes out ahead on efficiency depends on your actual operating point relative to the pump's best efficiency point, your total dynamic head, pipe friction losses, and how well the pump was sized for the job in the first place — not on the installation method alone. What submersible units do reliably save you is suction-side hydraulic loss and priming energy, which surface pumps have to account for. Well-selected industrial centrifugal pumps in this power class typically run in the 65–80% hydraulic efficiency range at their best efficiency point; where you land in that range depends far more on correct sizing than on submersible vs. surface configuration.
Where This Pump Gets Put to Work
You'll typically find a vertical submersible centrifugal pump like this one doing:
If your application also involves keeping solids in suspension inside a tank — think thickener feed boxes, agitated slurry sumps, or reagent tanks — that's a slightly different job, and it's worth knowing Hydroman also builds a submersible centrifugal agitator pump line specifically for that duty, combining a mixing/agitating mechanism with centrifugal pumping so solids don't settle out before they're pumped. It's a different product from the 100TJQ22-50H6A, but often specified alongside it on the same site.
A Quick Word on Pump-Type Terminology
Because these terms show up constantly in spec sheets and RFQs, it's worth being precise about what the 100TJQ22-50H6A is — and isn't:
It's a single stage centrifugal pump — one impeller, one pressure boost per pass, which is the standard configuration for drainage and transfer duty at this head range. It's a single suction design, meaning liquid enters the impeller eye from one side rather than two, which is typical for this pump size and keeps the hydraulic path simple.
It is not a single-phase unit — at 22 kW, the motor runs on three-phase power, as virtually every motor above a few kW does; single phase centrifugal pump models exist, but they're a small-motor, light-duty category, not this one. It's also not an end-suction horizontal design — if you're comparing options and a single stage end suction centrifugal pump or a horizontally mounted unit is what your system calls for, that's a different mounting configuration from this vertical submersible pump, even though both are single stage centrifugal at the hydraulic level. If your project genuinely calls for a vertical single stage centrifugal pump in a dry-mounted configuration rather than submerged, that's also a separate product line worth discussing with our engineers rather than assuming this model covers it.
Installation and Operation Notes
The pump is designed for vertical installation, lowered on guide rails or a lifting chain into the sump, pit, or tank. The 100 mm discharge connects to your pipeline via flange or hose coupling, and pipe sizing should match your actual flow rate to avoid unnecessary friction loss.
On the electrical side, the cable, control panel, and protection devices need to be matched to the 22 kW motor's actual full-load current and starting characteristics — this isn't something to eyeball, and we size it with you as part of the quotation. Depending on your site, a soft starter or VFD is often worth adding, both to control inrush current and to let you throttle flow without a physical valve.
The pump needs to stay submerged to the manufacturer-specified minimum level during operation — running it with the motor exposed, even briefly, is the single most common cause of premature motor failure in submersible pumps generally, not just this one. If your application involves fluctuating liquid levels, a 4 inch submersible pump with float switch control is worth specifying so the unit starts and stops automatically at safe levels rather than relying on someone watching the tank. Let us know at quotation stage if you want the float switch and control cabinet bundled in — it's a configuration option rather than a standard inclusion, so we confirm it against your exact setup instead of assuming it's already there.
Choosing the Right Pump for Your System
Before you commit to this model, run through these checks:
If any of these don't line up cleanly with the 100TJQ22-50H6A, that's useful information — it might mean a different motor size, a different impeller, or a genuinely different pump family (like the agitator or end-suction lines) is the better fit, and we'd rather tell you that upfront than sell you the wrong unit.
Built and Tested Before It Ships
Every Hydroman submersible pump goes through casting, precision machining, impeller balancing, and motor assembly under quality control, followed by factory performance testing — flow, head, insulation resistance, and running inspection — before it leaves the plant. Custom configuration is available on cable length, impeller material (for abrasive or corrosive liquids), control cabinet, VFD, float switch, and installation accessories, so the unit you receive matches your site conditions rather than a generic catalog spec.
What is a submersible centrifugal pump? It's a centrifugal pump — one that moves liquid by spinning an impeller — built into a sealed, watertight housing so the whole unit, motor included, can be installed directly underwater.
Is a submersible pump a centrifugal pump? Not automatically — some submersible pumps use positive-displacement mechanisms instead. But the large majority of industrial submersible pumps, including this one, are centrifugal.
What's the actual difference between a submersible pump and a centrifugal pump? They're not opposites. "Submersible" describes where and how the pump is installed; "centrifugal" describes the hydraulic principle it uses to move liquid. This pump is both.
Is this pump suitable for wastewater with solids? Depending on the impeller variant fitted, yes — but the maximum particle size and solids handling capability need to be matched to your specific wastewater characteristics before installation, not assumed.
What's the discharge size on the 100TJQ22-50H6A? 100 mm / 4 inch.
What does a submersible centrifugal pump price typically depend on? There's no single number that applies across the board — submersible centrifugal pump price is driven by motor power, the flow/head duty point, impeller material, any solids-handling requirements, control accessories like a float switch or VFD, order quantity, and shipping destination. Send us your duty point and we'll quote against your actual requirement.
Can this pump be fitted with a float switch? Yes, as a configurable option — let us know at inquiry stage so it's included in your control setup rather than added later.
How do I decide between a submersible pump and a surface-mounted centrifugal pump? Start with your installation environment. If the liquid source is a pit, sump, or tank and you want to avoid suction piping and priming, submersible is usually the simpler and more reliable choice. If you need a fixed, easily accessible pump house setup with straightforward on-site maintenance access, a surface-mounted unit may suit better. Flow, head, and liquid type matter in both cases.
Request a Quote for the Hydroman® 100TJQ22-50H6A
Need a 4-inch electric submersible centrifugal pump for a real project rather than a spec sheet exercise? Send us your required flow, required head, liquid type and temperature, solids content, discharge pipe size, power supply details, quantity, and destination country, and we'll come back with the correct configuration, technical data, and a firm quotation — not a generic price.
[Contact Hydroman® for a Technical Quote →]
Sara Liang
+86 189 3110 6396 (Whatsapp/Wechat)
Inquiry@tobeepump.com
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