Choose between MIL’S SIRELLA dry claw and EVISA oil-lubricated rotary vane pumps by starting with the pressure and flow your process needs. Then check gas compatibility, contamination requirements, maintenance and the exact electrical version. The technology name alone is not enough to specify a replacement.
Two distinctions matter: a dry pumping chamber can still have a lubricated gearbox, and end vacuum is not always the continuous operating limit. For example, the SIRELLA SL300.R datasheet lists 50 mbar end vacuum but 150 mbar continuous end vacuum at 50 and 60 Hz.
What changes between dry claw and rotary vane?
SIRELLA uses contactless claws to move and compress gas in a dry pumping chamber. EVISA uses oil-lubricated rotary vanes. These designs have different maintenance and operating requirements; neither provides an automatic answer for every application in a particular industry.
| Selection question | SIRELLA dry claw | EVISA rotary vane |
|---|---|---|
| Where is oil used? | The pumping chamber is dry. The SL300.R gearbox uses 1 litre of MB150S synthetic oil. | The pump uses operating oil. The E100.R sheet specifies 3 litres of MV99S synthetic oil. |
| Which pressure should I compare? | Use the continuous operating limit for sustained duty, plus the flow curve at your working pressure. | Check the exact standard or HV variant and the gas-ballast setting. These change the stated end vacuum. |
| What needs servicing? | Follow the model’s gearbox lubricant, filter and maintenance-kit requirements. | Follow the model’s oil, filters, seals and other service requirements. |
| Which uses less electricity? | Compare measured consumption or manufacturer data at the same pressure, flow and duty cycle. Motor rating alone does not establish running cost. | |
| Can it replace my current pump? | Check pressure, usable flow, gas load, connections, electrical supply, controls, cooling and maintenance access before selecting a replacement. | |
Read the model suffix and the test conditions
The EVISA E100.R sheet illustrates why a range-wide vacuum claim can mislead. Without gas ballast it lists end vacuum of ≤3 mbar for E100.R and ≤0.06 mbar for E100.R HV. With gas ballast open, different figures apply. A quotation should identify the variant and operating conditions, not simply say “EVISA”.
The same sheet distinguishes nominal flow from measured pumping speed: at 50 Hz, nominal flow is 100 m³/h, PNEUROP pumping speed is 96 m³/h, and pumping speed at 1 mbar for the HV version is 52 m³/h. These are different specifications, not interchangeable descriptions of capacity. The PNEUROP measurements are stated at 20°C.
Use performance curves to check the duty point
For a vessel that must evacuate in a set time, give Girovac both the vessel volume and the cycle-time requirement. For continuous operation, give the target pressure and gas flow. Pipework, leakage and process gas loads affect the result at the equipment.
The SIRELLA SL300.R product page includes the manufacturer’s pumping-speed and 1000-litre vessel pump-down curves, with the operating limits explained alongside them.
Cleanliness, vapours and hazardous processes
A dry chamber removes the need for oil in that chamber; it does not prove that the entire process is contamination-free or suitable for a specific gas. Explain any oil-sensitive process requirements, moisture, solvents, particles or reactive gases before selection. The E100.R documentation includes gas-ballast and water-vapour data that must be read for the chosen version and frequency.
For potentially explosive atmospheres or gases, provide the site’s equipment requirements and ask for the exact manufacturer certification and permitted use. Do not assume that a whole product family has the same approval.
What to send for a useful quotation
- Existing pump model, full suffix and a nameplate photograph.
- Required continuous pressure, flow, and any vessel volume or evacuation-time target.
- Process gases, vapours, particles and contamination limits.
- Hours of operation and whether demand changes during the day.
- Electrical supply, inlet and exhaust connections, controls and available space.
Browse MIL’S equipment, compare claw pumps with oil-lubricated rotary vane pumps, or ask Girovac to review your requirements.
Common selection questions
Does SIRELLA need oil?
The SL300.R pumping chamber is dry, but its gearbox needs the specified lubricant. Its datasheet lists MB150S oil and maintenance kits. “Oil-less” does not mean maintenance-free.
Can the SL300.R run continuously at 50 mbar?
The datasheet lists 150 mbar as continuous end vacuum and 50 mbar as end vacuum. Use the continuous-duty figure when discussing sustained operation and confirm the exact installation requirements.
Is a dry claw pump always cheaper to run?
No universal saving can be stated from the technology alone. Compare the complete installation at the required duty point, including electricity, servicing, consumables and hours of use.
Which range should you investigate first?
If your process needs a dry pumping chamber, start with the SIRELLA SL300.R and the other SIRELLA models in the MIL’S catalogue, then check the continuous operating limit. For lubricated rotary vane technology, compare the EVISA E100.R and the exact standard or HV configuration your pressure requirement calls for.
For a shared vacuum supply, use our central vacuum system selection guide to define simultaneous demand, receiver and control requirements. Choose the measurement equipment alongside the pump so you can verify the pressure at the process.
Do I need an ATEX version?
Share the classified area and process requirements before selection. The EVISA ATEX range page is a starting point for discussing the documented configuration; an approval for one version must not be applied to a standard pump or a different installation.
Can Girovac review a replacement without a full specification?
Yes. Send a nameplate photograph and tell us the duty the pump performs. Use the replacement equipment enquiry and include known pressure, flow, electrical supply and connections. We can then identify what needs checking before a quotation.
Manufacturer references
MIL’S SIRELLA SL300.R datasheet (PDF), pages 1–4; MIL’S EVISA E100.R / E100.R HV datasheet (PDF), first page, printed page 26. Figures above are model-specific examples, not a capacity-matched comparison. Content revised September 2026 against these documents. Confirm the current specification for the equipment being ordered.