Solenoid Metering Pump Manufacturers: Brands for Low-Flow Chemical Feed

Solenoid metering pump manufacturers are easy to list and harder to choose between. On water treatment, cooling tower and small wastewater jobs, the names we run into most are NEWDOSE, Iwaki, LMI, ProMinent, SEKO and Doseuro. All of them build solenoid diaphragm pumps covering a few liters per hour up to several tens of liters per hour, at pressures from a few bar to around 20 bar. The right one depends on your chemical, flow, backpressure and control signal, then on spares and support. This guide is for project engineers, buyers and maintenance teams. We describe only series that appear in the makers' own literature, and we do not rank anyone.

Solenoid metering pump manufacturers and what each focuses on

NEWDOSE: series split by control method

NEWDOSE offers four solenoid diaphragm series: DFD, DP, DM and DC. Its brochure states that DFD is adjusted manually on the panel, DP follows an external pulse signal and DM follows an external current signal. Head materials include PP, PVC, PVDF, SS316 and PTFE, which covers common acids, caustic and hypochlorite. See how the NEWDOSE DFD, DP, DM and DC series differ.

Iwaki: many liquid end options

The Iwaki EHN series is digitally controlled, with 1 to 360 strokes per minute and a universal AC100 to 240V supply in the catalog. Its strength is liquid end choice, including auto-degassing and high-pressure heads. For gassing chemicals such as hypochlorite or hydrogen peroxide, an auto-degassing head saves a lot of trouble.

LMI: Milton Roy's solenoid line

LMI is the Milton Roy brand dedicated to solenoid pumps. In its literature the P+ series reaches 15.1 L/h and 17.2 bar with 4 to 20 mA and pulse control, the D series reaches 90 L/h and 18 bar, and the EXCEL AD series offers turndown up to 1000:1. Its FASTPRIME liquid end makes priming straightforward.

ProMinent and SEKO

ProMinent, from Germany, is a common sight on water treatment projects, and gamma/X is its smart solenoid series. SEKO, from Italy, has a broad solenoid range: TEKNA and TEKBA up to 54 L/h and 20 bar, KOMPACT and KOMBA up to 9 L/h and 10 bar, INVIKTA up to 6 L/h and 7 bar. Details are in SEKO solenoid pump models explained.

Doseuro SDP

Doseuro is known mainly for plunger and mechanical pumps, and its solenoid model is the SDP: microprocessor control, reinforced PP housing, solid PTFE diaphragm and IP65, aimed at drinking water and cooling tower duty with constant or proportional feed.

These are the solenoid metering pump manufacturers we meet most often, not a complete list. Our metering pump brands page covers more names.

How to compare solenoid metering pump manufacturers

A list is the easy part. When we help clients compare solenoid metering pump manufacturers, we work through these questions in order:

1. Does the liquid end suit the chemical? Ask which heads (PVDF, PTFE, SS316) are in stock and what the balls and seals are made of. The wrong seal on hypochlorite can leak within months.
2. Is there a degassing head? Hypochlorite and peroxide release gas. Without an auto-degassing head or a manual bleed valve, gas lock becomes routine.
3. Are the control inputs enough? For PLC integration, check for 4 to 20 mA input, pulse input, low-level alarm input and any fieldbus option you need.
4. Is there pressure margin? Higher-pressure solenoid models usually deliver less flow. The rated pressure must exceed the maximum pressure at the injection point.
5. Spares and service. Fast access to diaphragms, valve sets and injection valves matters more over the years than the purchase price. Solenoid metering pump manufacturers with local stock turn a failed diaphragm into a quick fix instead of a long shutdown.

An often-missed trap: solenoid pumps stroke quickly, and long, thin discharge lines produce strong pulsation. Some brands recommend a pulsation dampener or backpressure valve. Send line length and injection pressure with your enquiry so flow stability is not a surprise after installation.

Solenoid metering pump manufacturers vs general chemical dosing pump suppliers

They overlap but are not the same. Chemical dosing pump suppliers also cover mechanical diaphragm, hydraulic diaphragm and plunger pumps plus complete dosing skids. Solenoid metering pump manufacturers are the subset building low-flow electronic pumps. Some do both, NEWDOSE and SEKO among them, which lets one supplier cover small and large pumps on the same project and simplifies spare parts.

Once flow climbs into hundreds of liters per hour, or pressure goes well beyond the solenoid range, move to a mechanical or hydraulic pump rather than forcing a solenoid model to fit. For a side-by-side view of control options, IP rating and support, read solenoid dosing pump brands compared.

Conclusion

The solenoid metering pump manufacturers most buyers will shortlist include NEWDOSE, Iwaki, LMI, ProMinent, SEKO and Doseuro, each with its own emphasis: NEWDOSE splits series by control method, Iwaki offers many liquid ends, LMI primes easily, SEKO steps its range by flow, and Doseuro offers the SDP. Judge a supplier on head materials, degassing design, control inputs, pressure margin and spare parts, not on the logo. Browse solenoid diaphragm metering pumps to filter models, then send your chemical, flow, pressure and control method and contact our engineers for a shortlist.

FAQ

Is there a big gap between imported and Chinese solenoid metering pump manufacturers?

It depends on the series. Differences show up mainly in control features, liquid end options and long-term stability. For routine acid or caustic feed, mainstream Chinese series usually do the job.

Can one site mix pumps from different solenoid metering pump manufacturers?

Yes, but spares get complicated. Standardize on one or two brands where you can.

What documents should solenoid metering pump manufacturers provide?

A selection catalog, an instruction manual and a material compatibility chart. Read the manual before ordering to confirm installation and wiring.

Which head should I pick for low-flow hypochlorite?

One with auto-degassing or a bleed valve, oxidation-resistant head and valve materials, short tubing, and no direct sun or heat.

How much flow can a solenoid pump deliver?

It varies by series. In our literature the LMI D series tops out at 90 L/h and SEKO TEKNA at 54 L/h. Above that, a mechanical diaphragm pump is the usual move.