Doseuro – solenoid dosing pump for low reagent flow rates SDP
Doseuro SDP dosing pump - solenoid diaphragm metering pump for low flow rates. Flow rate - from 1 to 22 l/h, pressure - from 1 to 20 bar depending on the model and stroke length adjustment.
The casing is made of reinforced polypropylene, which is resistant to corrosion, and the diaphragm is made of solid PTFE. Enclosure rating IP65. Control is via an integrated microprocessor.
Steiner Ukraine supplies Doseuro equipment to Ukraine: selection according to reagent and duty point, supply, service, spare parts.
What is a Doseuro SDP dosing pump?
This is a pump without rotating parts. Instead of a motor and gearbox, it has an electromagnet: a coil pulls in the core, the core pushes the diaphragm, and the diaphragm displaces a dose of reagent. A spring returns the system back.
A consequence of the design is that the stroke frequency is fixed and equal to 120 beats per minuteThe feed is regulated in two ways: by stroke length from 0.8 to 2.2 mm and by stroke frequency via a microprocessor.
No rotating shaft means no shaft seal or mechanical seal. This removes the most frequent point of failure from the pump.
The SDP series is part of the model range Doseuro — from the Italian dosing equipment manufacturer of the FPZ group.
Which models are in the series?
There are six models in the manufacturer's catalogue. Each is available with several stroke length settings, and each setting provides its own "delivery-pressure" pair.
| The model | Flow rate range, l/h | Pressure range, barg |
|---|---|---|
| SDP 115 | 1–5 | 2–15 |
| SDP 220 | 2–5 | 2–20 |
| SDP 507 | 5–8 | 2–7 |
| SDP 810 | by 11 | 2–12 |
| SDP 154 | 15–17 | 1–4 |
| SDP 203 | 20–22 | 1–3 |
Overall series limits: flow rate from 1 to 22 l/h, pressure from 1 to 20 barg.
Why are flow rate and pressure inversely related?
The table above shows a pattern: the greater the model's delivery rate, the lower its pressure.
The cause is physical. The electromagnet develops a fixed force. This force is distributed between two quantities: how much reagent to displace per stroke and against what pressure.
| Settings | What you get |
|---|---|
| Short stroke | lower dose, higher pressure |
| Long corridor | higher dose, lower pressure |
Therefore, model selection begins not with the feed, but with value pairswhat is the required dosage and against what backpressure in the line.
The SDP 220 model delivers 22 barg, but only 2 l/h. The SDP 203 model delivers 22 l/h, but only up to 3 barg. These are two different tasks.
What materials is the Doseuro SDP dosing pump made of?
| Node | Material |
|---|---|
| Pump casing | corrosion-resistant reinforced polypropylene |
| Membrane | solid PTFE |
| Parts in contact with the reagent | PP, PVC, PTFE, PVDF to choose from |
| Degree of protection | IP65 |
Solid PTFE in the membrane, it is not a coating, but a solid material. PTFE has the widest chemical resistance of all polymers and does not swell in aggressive reagents.
IP65 means complete protection against dust and against water jets from any direction. The pump can be washed in place and placed in damp rooms.
The reagent determines the choice of the wet-end material. PVDF is usually used for hypochlorite and strong oxidising agents, PP for acids and alkalis, and PVC for moderately aggressive aqueous solutions.
What management functions are available?
The manufacturer offers four microprocessor versions.
| Implementation | Function |
|---|---|
| SMC | analogue control |
| SMM | digital control |
| SSW | multifunction control |
| SMF | built-in pH, Rx (redox potential) or chlorine control |
The SMF unit combines a pump and a controller in a single housing. It measures the parameter itself and automatically regulates the flow to the setpoint, without the need for a separate controller in the control cabinet. For a small water treatment plant, this eliminates the need for a separate device in the design.
Power supply: Standard: 230 V, 50/60 Hz. Versions are available in 24 V DC, 12 V DC, 24 V AC and 110 V.
What is included in the delivery set?
| Position | Purpose |
|---|---|
| Injection valve | connection to the pipeline, non-return valve to prevent backflow |
| Suction tube, 1.5 m | reagent withdrawal from the vessel |
| Pressure pipe | feed to the entry point |
Maximum suction height is 2 metres. Standard tube connection is 4/6 mm.
The kit allows you to start the pump without purchasing any additional pipework.
When to choose a Doseuro SDP dosing pump and when a mechanical one?
| Condition | solenoid valve | SR and PDP mechanical series |
|---|---|---|
| Flow rate up to 22 l/h | suits | excessively |
| Flow rate over 22 L/h | Doesn't fit | SR up to 1,400 litres per hour, PDP up to 4028 l/h |
| Pressure over 20 bar | Doesn't fit | up to 250 bar |
| Compliance with API 675 is required | none | PDP |
| ATEX compliance is required | not stated | SR and PDP |
| Built-in pH or chlorine monitoring is required | SMF implementation | separate controller |
| Compactness and low weight | advantage | larger dimensions |
Rule of thumb: SDP pumps are used where the reagent requirement is small and precise—such as chlorine dosing, coagulant dosing, or pH control in a small loop. Mechanical series are required for process flow rates.
For which processes is the SDP series used?
The manufacturer addresses the series to low-flow applications. According to Doseuro's list of industries, these are:
| Process | What are they dosing |
|---|---|
| Drinking water treatment | coagulants, flocculants, pH neutralisation reagents, chlorine, antiscalants |
| Spray booths with a water curtain | flocculants, antifoaming agents, pH regulators |
| CIP equipment cleaning | acid and soda |
| Swimming pools and industrial water | hypochlorite, pH regulators |
| Food industry | acid, soda, citric acid in small doses |
SMF execution with built-in pH, Rx or chlorine control is designed precisely for such loops – where the parameter needs to be automatically kept within a given range.
Frequently asked questions about the Doseuro SDP dosing pump
What is the maximum flow rate?
22 l/h — model SDP 203.
What is the maximum pressure?
20 bar — SDP 220 model configured for a shorter stroke.
Why is it not possible to get both 22 l/h and 20 bar at the same time?
The electromagnet develops a fixed force. It is distributed between the dose per stroke and the backpressure. A larger dose means a lower permissible pressure.
How many models are in the series?
Six: SDP 115, 220, 507, 810, 154, 203.
What is the case made of?
Made of corrosion-resistant reinforced polypropylene. The membrane is made of solid PTFE.
What materials are available for contact with the reagent?
PP, PVC, PTFE and PVDF.
What is the degree of protection?
IP65 — complete protection against dust and jets of water.
Can a pump be controlled by a pH or chlorine signal?
Yes, SMF execution has built-in pH, Rx or chlorine control. In addition to it, analogue (SMC), digital (SMM) and multifunctional (SSW) control are available.
What is the stroke rate?
120 strokes per minute. The stroke length is adjustable in the range of 0.8–2.2 mm.
What is the maximum suction lift?
2 metres.
What is included in the delivery?
Injection valve, 1.5 m suction tube and delivery tube. Connection 4/6 mm.
What is the power supply?
Standard 230 V 50/60 Hz. Versions for 24 V DC, 12 V DC, 24 V AC and 110 V are available.
Enquiry for selection and price via ContactsOther equipment from the manufacturer — DoseuroMechanical series of greater feed: Spring return and Positive return. Sections: Pumps and systems, Pumps for food production, Spare parts.
